SE546592C2 - A strengthening glove, a control system, and methods for dynamically controlling the sensitivity of a strengthening glove - Google Patents

Abstract

The technology disclosed relates to a strengthening glove (100) with at least one glove finger (101, 102, 103. 104. 105) and comprising a control system (200) arranged to strengthen a gripping movement performed by a human hand (10) wearing the glove (100). Sensor means (210) is arranged to detect a respective force in at least one measurement location. The control system (200) comprises at least one actuator (240) arranged to impart a force to a respective at least one of the glove fingers (101, 102, 103, 104. 105) and read respective sensor measurement values from the sensor means (210). The control system (200) controls the machine output force applied by the at least one actuating means (240) using a force strengthening feedback loop based upon sensor measurement values read from the sensor means (210). The control system (200) is further configured to dynamically control the relationship between the sensor input force detected by the sensor means (210) and the machine output force of the actuating means (240) for the release of a grasp following a gripping movement.

Description

TECHNICAL FIELD The technology disclosed relates to a strengthening glove, or force-assisting glove, in other words a glove arranged to be worn by a human hand and used for strengthening a gripping movement executed by one or more fingers of the hand. The technology disclosed also relates to a control system for use in a strengthening glove, and methods for operating a strengthening glove.

BACKGROUND The technology disclosed relates to a strengthening glove, or force-assisting glove, arranged to be worn by a human hand and used for strengthening a gripping movement executed by one or more fingers of the hand. The technology also relates to a control system for a strengthening glove, and methods for operating such a strengthening glove.

Such strengthening gloves are known, using different operating principles, such as arranging individual driving units on each finger to be strengthened or by using wires or cables, such as artificial tendons, in order to apply pushing and/or pulling forces onto particular points on each finger to be strengthened. For instance, electric or pneumatic driving mechanisms may be employed.

One example of such a glove is described in US 8,029,414 B2, using artificial tendons fastened to strengthened fingers and driven by a central control system, in turn applying pulling forces to the tendons.

Such a glove operates to offer general strengthening of the movements of the human hand wearing the glove. For instance, when the human hand grips an object, the gripping force applied by the human user is amplified to strengthen the grip. Typically, the machine output force applied by the control system via the actuators of the strengthening glove as a function of the detected sensor input force is the same for the gripping movement as for the release of a grasp following the gripping movement.

US 2013226350 A1 discloses a strengthening glove with specific gripping features, initiated using a separate control device.

EP 2417941 A discloses a movement assisting glove with a biosignal detection part configured to detect a biosignal that causes a finger of a wearer to move.

PROBLEMS WITH THE PRIOR ART The various tasks and actions performed by a strengthening glove, or force-assisting glove, require a suitable aid and an applied machine output force which is adapted to whether it is a gripping movement or a release of a grasp following a gripping movement.

Typically, the machine output force applied by the control system via the actuators of the strengthening glove as a function of the detected sensor input force is the same for the up-ramp of the gripping movement as for the falling sensor input force values following the release of a grasp.

A problem when using such a strengthening glove is therefore that, to provide the user with a proper response and user experience to the intention by the human hand or finger to release a grasp, the gripping movement and the release of a grasp following a gripping movement require different machine output forces for the same detected sensor input force. For instance, it may be difficult to provide a preper response to en intention by the human hand nr finger te release a grasp foltewing the gripping movement using the same sensitivity used for the gripping movement ln addition, the sensor measurement values obtained by the sensors means of the strengthening glove during a movement, e.g. gripping movement, are subjected to different factors that have an impact on and constantly and continuously changes the measurement values obtained during operation and over time. For example, the range of the sensor input force values detected by at least one sensor of the glove, e.g. detected by pressure and/or force sensors, and the thereby the machine output force applied via the actuators, may depend on the nature of the different tasks performed by the strengthening glove.

Furthermore, the force or pressure detected by the sensors, and thereby also the machine output response applied by control system via its actuators, may also depend on the response sensitivity of the sensors and the physical and mechanical properties of the gloves, including the aging of the gloves and their sensors.

The problems with prior art force-assisting gloves, or strengthening gloves, also include that the properties of these gloves and their sensors typically vary over time and between individual gloves. For instance, it may be difficult to provide a proper and suitable combined grasping force of the user and the control system of the glove when releasing a grasp following a gripping movement. lt may therefore be difficult to provide a proper and suitable combined grasping force of the user and an applied machine output force during the release of a grasp when the control and sensitivity of the glove is solely based on a set of fixed parameters and/or fixed control programs or when parameter values for controlling the glove may only be changed manually.

Thus, there is a need for a strengthening glove and methods for quick and improved response to the user's intentions of releasing a grasp to thereby provide for an improved control and user experience.

SUMMARY The technology disclosed relates to a strengthening glove, or force-assisting glove, in other words a glove arranged to be worn by a human hand and used for strengthening a movement, e.g. a gripping movement, executed by one or more fingers of the hand.

The objective of the strengthening glove and control system of the technology disclosed is to improve the control of the machine output force applied by the actuating means of the glove by providing a more suitable machine output force response for the intention by the user of the glove to release a grasp following a gripping movement. This objective is achieved by using a separate algorithm/function for the sensitivity during release of a grasp and/or dynamically recalculating the relationship betvveen the sensor input force detected by the sensor means and the machine output force applied by the actuating means of the glove, e.g. in response to detecting a current sensor input force that yields a maximum output force applied. ln aspects, the technology disclosed relates to a control system of a strengthening glove and methods for a quick and improved response to the user's intentions of releasing a grasp to thereby provide for an improved user experience. ln particular, the technology also relates to the control of a strengthening glove, and a control system and methods for operating such a strengthening glove by using a separate algorithm/function for the sensitivity during release of a grasp and/or dynamically recaicuiating the sensitivity. e.g. a sensitivity parameter vaiue, determining the machine output force applied by at ieast one actuating means as a function of sensor measurement veiues obtained front at ieasi ene sensor mêåiiïâ. ln aspects, the control system of the technology disclosed is configured to control the sensitivity of the glove and thereby the machine output force applied by the at least one actuating means during a gripping movement using a force strengthening feedback loop based upon sensor measurement values read from at least one sensor arranged in the at least one measurement location, where the sensitivity of the glove is controlled by a separate algorithm/function for the sensitivity during release of a grasp and/or dynamically adjusted or recalculated in response to determine, by the controi system, that the sensor measurement vaiues currently obtained from the at ieast one sensor means is higher than a sensor input force value that yieios a maximum machine output force appiied for the gripping movement. ln embodiments, the control system is configured to use a separate algorithm/function for the sensitivity during release of a grasp and/or oynamicaiiy reoaiciiiate the reiationship between the sensor input force detected by the at least one sensor means and the machine output force applied, eg. a sensitivity parameter vaiue, so that faiiing sensor measurement iraiues obtained from the at ieast one sensor means indicating an intention by the human hand or finger to reieese a grasp fotiovving the gripping movement vvouid resuit in a faster response in appiying a machine output force that is tower than the maximum machine output force appiied for the gripping movement. The reiationship may then be dynamicaiiy recaicuiated in response to determining that the sensor measurement vaiues currentiy obtained front the at ieast one sensor means is higher than a sensor input force vaiue that yieids a maximum machine output force appiied for the gripping rnovemertt.

According to aspects of the technology disclosed, the control system is configured to dynamically recalculate the relationship between the sensor input force detected by the at least one sensor means and the machine output force applied to the respective at least one glove finger via at least one actuating means for an ongoing gripping movement, where the relationship is dynamically adjusted or recalculated in response to determining, by the controi system. that the sensor measurement vaiues currentiy' obtained from the at ieast one sensor means is higher than a sensor input force vaiue that yieids a maximum machine output force appiied for the gripping movement. in aspects and embodiments, the controi device is configured to, in response to determining that the sensor measurement vaiues currentiy obtained from the at ieast one sensor means is higher than a certain fthrestioid) sensor input force vaiue yieiding a maximum machine output force, use a separate algorithm/function for the sensitivity during release of a grasp and/or dynamicaiiy recaicuiate the relationship between the sensor input force detected by the at least one sensor means and the machine output force applied, eg. a sensitivity parameter vaiue, so that faiiing sensor measurement vaiues obtained from the at ieast one sensor means indicating an intention by the human hand or finger to reiease a grasp foiioiiiing the gripping movement vvouid resuit in a oecreasing machine output force aiso for sensor measurement vaiues higher than the threshoio sensor input force vaiue.in embodiments, the controi system is corttigureri to use a separate algorithm/function for the sensitivity during release of a grasp and/or dynamieaiiy recatcuiate the sensitivity function determining the aopiied machine output force for faiting sensor input force vatues during the reiease ot a grasp, or down-ramp, se that the apoiieo machine output torce et the recaicuiated sensitivity function are tower tor at ieast the sensor input force vaiues yieiding a maximum output torce tor the gripping movement. in embodiments, the sensitivity function ot the dovvnramp, i.e. taiiing sensor input torce vaiues, resuits in a fonter appiied machine output force than the sensitivity function tor the up-ramp, i.e. increasing sensor input tfaiues for the gripping movement. aiso tor sensor input force vaiues oeiew a threshoid sensor input force vaiue ot the up-ramp that yieids e maximum otitput teroe tor the gripping movement. ln embodiments, the control system may then be configured to dynamicaiiy recaieuiate the sensitivity tunction ih response to determining that the ourrentiy detected sensor input torce yieids a maximum output torce. The control system of the technology disclosed may then be configured to automatically and dynamically determine and/or adjust the relationship between the sensor input force detected by the at least one sensor means and the machine output force applied to the respective at least one glove finger by the control system via the at least one actuating means for the gripping movement in response to uetermining that the sensor measurement vaiues currentiy obtained from the at ieast one sensor nteans is higher than a sensor input force vatue that yieids a pre-determineu (ie. determined betore the ourrent gripping movement) maximum machine output torce appiied tor the gripping movement. ln various embodiments of the technology disclosed, the softvvare and/or hardware of the same control system may also be configured to control, for an ongoing gripping movement, the machine output force applied via the at least one actuating means in accordance with the determined, e.g. automatically and dynamically adjusted/recalculated, relationship between the sensor input force detected by the at least one sensor means and the machine output force applied for sensor input force values above a threshold sensor input value yielding a maximum machine output torce appiied for the gripping movement. ln embodiments, the control system may then be configured to use a separate algorithm/function for the sensitivity during release of a grasp and/or dynamicaity recaicuiate the reiatioitship between the sensor input force detected by the at least one sensor means and the machine output force applied, e.g. a sensitivity parameter vaiue. so that taiiing sensor measurement vaiues ohtained trom the at ieast one sensor nteans indicating an intention by the human hand or finger to reiease a grasp toiiovving the gripping movement tvouid resutt in a tester response in appiying a machine output torce that is tower than the maximum machine output force appiied tor the gripping movement. ln embodiments, the strengthening glove of the technology disclosed consists of a glove-like device comprising artificial tendons running through ducts and/or sown into the fingers, which typically are connected to a power unit. The power unit may then be part of an actuator means comprising at least one actuator for pu||ing on the artificial tendons to thereby strengthen a movement imparted by the user, e.g. a gripping movement. According to embodiments of the technology disclosed, the actuator means are controlled by the control system of the strengthening glove in that the relationship between the sensor input force detected by the at least one sensor means and the machine output force applied may be dynamically recalculated by the control system during a gripping movement and in response to determining that the currently detected sensor input force is above a threshold sensor input force yielding a maximum machine output force. in embodiments, the control ttetfioe is configured to use a separate algorithm/function for the sensitivity during release of a grasp and/or ttynamioaiitf recaieutate or adjust the sensitivity, i.e. the reiationship between the sensor input force and the machine output force applied, se that falling sensor input force values following the release of a grasp has a different sensitivity than the pre~deterntined sensitivity function for the same sensor input force values during the constantly increasing machine output force of the up-ranip ot the gripping movement. "the taiiing sensor input force vaiues detected during a reiease of the grasp, or tiownrantp, wouiti then typicaiiy resuit in an appiied ntachiiie output force that is tower than the niasiiiite output toroe appiied for the exaot same sensor input force vaiues during the uorarnp, aiso for sensor inout force vaiues for the uti-ramp beiow a threshoio sensor input force vaiue that gvieids a maximum output force. in enihodinients, the continuously and dynamically adjusted sensitivity, i.e. relationship between the sensor input force detected and the machine output force applied, which is continuously and dynamically adjusted during the release of the gripping movement (e.g. in accordance with a sensitivity function for the release) is then typically again adjusted and changed for the up-ramp of the next gripping movement. ln example embodiments, the control system may be configured to, e.g. during or following the completion of the release of a gripping movement, automatically re-adjust the sensitivity so that the sensitivity function used for the up-ramp for the next gripping movement is corresponding to the sensitivity function, e.g. a linear or non-linear function, used for the up-ramp for the previous (e.g. immediately preceding) gripping movement. ln certain embodiments, the control system may be configured to continuously adjust the sensitivity (i.e. the applied machine output force as a function of detected sensor measurement values) for the up- ramps of consecutive gripping movements in accordance with the same first sensitivity function and maybe configured to continuously and dynamically adjust the sensitivity for the releases of consecutive gripping movements in accordance with the same second sensitivity function where the second sensitivity function is a different sensitivity function from the first sensitivity function. in embodiments, the oontroi device is configured to use a separate algorithm/function for the sensitivity during release of a grasp and/or oyitamicaiiyf recaicuiate or adjust the sensitivity function, i.e. the reiationship betvveen the sensor input force and the machine output force applied, so thet feiiing sensor input force values following the release ot a grasp has a different sensitivity function than the sensitivity function for the seme sensor input force values during the constantly increasing machine output force of the up-ramp ot the gripping movement. The appiied machine output force ot the sensitivity tunction ot the faiiing sensor input force vaiues during the reieese of a grasp, or down-ramp, vvouid then tycicaiiy aitvays he iovver than the appiieo machine output force of the sensitivity function for the up~ramp ot the gripping movement. in embodiments, the sensitivity function of the dovvn~ramp restiits in a icvver appiied machine output force than the sensitivity function tor the Lip-ramp aiso for sensor input force vaiues heiovv a threshoid sensor input force vaiue of the up-ramp that yieids a maximum output force. in embodiments, the contrci device is ccnfigured to dynamicaiiy receicuiate or adjust the sensitivity pararneter vaiue rietermining the reiationshio betvveen the sensor input force and the machine output force applied so thet taiiing rneasurement vaiues ohtained trcm the at ieast one sensor nteans indicating en intention hy the ituman hand cr finger to reiease a grasp foiiovving a gripping movement vvouid resuit in a decreesing machine output force appiied hy at ieast one of the at ieast one actuating means. ln embodiments, the control system is configured to dynamicaiiy recaicuiate the reiationship or sensitivity ceranieter vaiue according to e predefined eigorithm so that the receicuiated sensitivity parameter is iotver at ieast for sensor measurement vaiues higher than the certain threshcid sensor input force veiue yieiding e maximum machine output force. The oontrci device is therehy configured to dynamicaiiyf aoitist the reiaticnship or sensitivity paranieter vaiue so that faiiing measurement vaiues obtained from the at ieast one sensor means indicetiiig an intention hy the human hand or finger to reiease a grasp toiioiiiriifg a gripping movement vvouici resuit in a decreasing machine output force eppiied hy at ieast one of the et ieast one eotuating means. ln embodiments, the technology disclosed relates to a control system for controlling the machine output force applied for a strengthening glove where the control system is configured to determine whether the sensor measurement vaiues currentiy obtained from e force detecting sensor means is higher then a certain sensor input force tfeiue that is the iovrest threshoiri sensor input force veiue that yieids a maximum machine output force appiieri for the gripping movement, and, in response to deterrnining that the sensor measurement vaiues currentty obtained from the at ieast one sensor means is higher than the certain sensor input force vatue recaicuiate a sensitivity pararneter vaiue determining the rriaohine output force appiied as a function of the sensor measurement vaiues obtained from the at ieast one Sêiiâül" fïiêàfiå. ln embodiments, the technology disclosed relates to a control system for controlling the machine output force applied for a strengthening glove where the control system is configured to dynamicaity recaiouiate the sensitivity, ie. the retationship between the sensor input force detected and the appiied machine output force, for sensor measurement vaiues ahove a towest threshotd sensor input force vaiue yieiding a maximum machine output force. ln embodiments, the technology disclosed relates to a control system for controlling the machine output force applied for a strengthening glove where the control system is configured to dynamicaiiy recaicufate the sensitivity, ie. the refationship between the sensor input force detected and the appiied machine output force, for sensor measurement vaiues above a iowest threshoid sensor input force vaiue yieiding a maximum machine output force so that the recafcuiateoi sensitivity parameter vaiue is iovver for sensor measurement vaiues higher than the iowest threshoid sensor input force vaiue yieiding a maximum machine output force, tiiereby a faiiing sensor measurement ifatue obtained from the at ieast one sensor means indioating an intention by the human hand or finger to reiease a grasp foiiowing a gripping movement tvouid resutt in a faster response in appiying a machine output force that is tower than the maximum machine output force appiied for the gripping movement. ln embodiments, the technology disclosed relates to a control system for controlling the machine output force applied for a strengthening glove where the control system is configured to dynamicaity recaiouiate the reiationship/sensitivity, eg. by using a predefined aigorithm or function, so that the continuousiy recaicufated sensitivity parameter vaiue keeps fafiing as the sensor measurement vaiues obtained from the at ieast one sensor means keeps rising above the iovvest threshoid sensor input force vaiue yieiding a maximum machine output force, so that a fafiing sensor measurement vaiue obtained from the force detecting sensor means indicating an intention by the human hand or ringer" to reiease a grasp foiiowing a gripping ntovement wouid resuit in an appiied machine output force that is tower than the maximum force appiied for the gripping movement. ln embodiments, the technology disclosed relates to a control system for controlling the machine output force applied for a strengthening glove where the control system is configured to recaiouiate, eg. in response to determining that obtained sensor nieasurernent tfaiues are above a threshoio sensor input force vfaiue yieiding a maximum output force, the sensitivity determining the reiationship netvveen the appiied machine output force and the sensor input force according to a predeiined aigorithm or function using increasing sensor measurement vaiues continuousiyf obtained from the at ieast one sensor means ouring the gripping movement so that the recaicuiated appiied machine output force as a function of increasing sensor measurement tfaiues ahove the iovrest thresnoid sensor input force yieiding a maximum output force is sirhstantiaiiy constant and corresponos, or suostantiaiitf corresponos to the maximum force appiied for the gripping movement, therenyf a taiiing sensor measurement vaiue obtained from the force detecting sensor nieans indicating an intention hv the human hand or finger to reiease a grasp foiiowing the gripping movement ifvouid resuit in an appiied machine output force that is iovver than the niaximum machine output force apptied for the gripping movement. ln embodiments, the technology disclosed relates to a control system for controlling the machine output force applied for a strengthening glove where the control system is configured to recalculate the sensitivity/relationship using the foiiovving formuia for sensor input force vaiues greater than a iovvest sensor input force vaiue yieiriing a rnaximurn output force for the gripping movement: ídynamic = Sgtefatiit * (fQsensorAtSaturation -« iïsensortnresnoidytrïsensorniax m ifwsensorthreshoid), where-in Smdynamic is the recaicuiated sensitivity parameter vaiue determining the machine output force as a rfurtction of a detectert sensor input force above the certain sensor input force vaiue, Fmsensorthreshoid is the threshoid sensor input force vaiue heioia which no machine output force is appiieo, F_sensormax is the maximum sensor input force detected for the gripping movement, flsensorhtåaturation is the currentiyf detected sensor input force vaiue higher than a iotvest sensor input force vaiue yieiding a maximum machine output force for the gripping movements and Sjefauit is the defauit sensitivity parameter tfaiue or iinear sensitivity function determining an increased machine output force response as a function of an increasing sensor input force above the threshoid sensor input force vaiue neiovv vvhich no machine otrtput force is appiied and heiotv said tott/est sensor input force vaiue yieiding a maximum machine output force for the gripping movement, and irvhich is typicatiy set hy the user of the giove. ln aspects, the technology disclosed relates to a method for operating a strengthening glove with at least one glove finger and comprising at least one sensor means with at least one sensor arranged in at least one measurement location for detecting a respective force and a control system including at least one actuating means, the method comprising using a separate algorithm/function for the sensitivity during release of a grasp and/or dynamically recaicuiating the reiaticnship between the machine otrtput force apoiied and the input sensor force obtained frorn at ieast one sensor means of the strengthening gicve. ln aspects, the technology disclosed relates to a method for operating a strengthening glove with at least one glove finger and comprising at least one sensor means with at least one sensor arranged in at least one measurement location for detecting a respective force and a control system including at least one actuating means, the method comprising using a separate algorithm/function for the sensitivity during release of a grasp and/or dynamically recaicuiating a sensitivity parameter vatue determining the machine output force aopiied hy the at ieast one actuating means as a function of sensor measurement vaiues obtained from at ieast one sensor means of the strengthening gtove. ln aspects, the technology disclosed relates to a method for operating a strengthening glove with at least one glove finger and comprising at least one sensor means with at least one sensor arranged in at least one measurement location for detecting a respective force and a control system including at least one actuating means, the method comprising using a separate algorithm/function for the sensitivity during release of a grasp and/or dynamically adjusting/recalculating the reiationship between the sensor input force and the machine output force applied in response to deterrnining, hy the controi system, that the sensor rrieasuremerit vaiues currentiy obtained from the at ieast one sensor means is iiigirer than a sensor input force vaiue that yieids a maximum machine output force appiied for the grioping movement, in aspects, the technotogy' disciosed retates to a method tor operating a strengthening giove tvitii at ieast one gtove finger, tfvhich giove is arranged to strengthen a gripping movement performed hy a human hand vvearing the gtove, which giove comprises at ieast one sensor means arranged to detect, in at ieast one measurement tocation on the patm side of the at ieast one gicve finger, a respective force between a respective human finger vvearing the respective giove finger and a respective contact surface onto vvhich said gripping ntoverriertt is appiied, vvhich giove further comprises at ieast one actuating means arranged to impart a force to a respective at ieast one of said giove fingers, which giove further cornprises a controi device, arranged to read a respective sensor measurement vaiue from the at ieast one sensor means for each of the at ieast one measurement iocation and to oontroi the respective machine output force appiied try the at ieast one actuating means using a force strengthening feedhack ioop hased upon the sensor measurement tfaiues, the method confprising the steps of: a) continuousiy readinc, hy the controi device and during a gripping ntoverriertt, sensor measurement ifaiues obtained from the at ieast one sensor means and for each oi the at ieast one nreasurenrent focation; b) determining, by the controi device, whether the sensor measurement veiues currentiy obtained from a force detecting sensor means is higher than a certain sensor input force vaiue that is the iovvest sensor input force vaiue thet yieids a maximum machine output force appiied for the gripping movement, and, in response to deterrnining that the sensor measurement vaiues currentiy obtained from the at ieast one sensor means is higher than the certain sensor input force vaiue: c) recaicuiating, hy the controi device, a sensitivity pararneter vaiue and/'or using a separate algorithm/function for the sensitivity during release of a grasp to determine the machine output force appiied as a function of the sensor measurement vaiues obtained from the at ieast one sensor means. ln embodiments, the recaiouiating step of the method according to the technology disciosed is comprising dynamioaiitf recaicuiating the sensitivity, i.e. the reietionship hetvveeri the sensor input force detected and the appiied machine output force, for sensor measurement vaiues above a iovrest threshoid sensor input force vaiue yieiding a maximum machine output force so that the adjusted or recaicuiated sensitivity parameter vaiue is iovver for sensor nreasurenrent vaiues higher than the iovvest threshoid sensor input force vaiue yfieiding a maximum machine output force, thereby a faiiing sensor measurement vaiue obtained from the at ieast one sensor means indicating an intention hy' the human hand or finger to reiease a grasp foiiovving a gripping movement vvcuid resuit in a faster response in appiyring a machine output force that is iovver than the maximum machine output force appiied for the gripping movement ln embodiments, the recaiouiating step of the method according to the technology disciosed is comprising dyrnarriicaiiy recaiouiating the reiationshipisensitivity, e.g. hy using a predefined aigorithm or function, so that the continuousiy adjusted or reoaicuieted sensitivity parameter rfaiue ite-eps faifing as the sensor measurement vaiues obtained from the at ieast one sensor means keeps rising above the iorvest threshoid sensor input force vaiue yieiding a maximum machine output force, so that a faiiing sensor measurement vaiue obtained from the force detecting sensor means indicating an intention hy the human hand or finger to reiease a grasp foiiovrfing a gripping movement vvouid resuit in an appiied machine output force that is tower then the maximum force eppiied for the gripping movement. ln embodiments, the recaicuiating step of the method according to the technology disciosed is comprising dynarnioaiiy recaicuiating, in response to deterrnining that obtained sensor measurement vaiues are above a threshoid sensor input force rfaiue yieiding e maximum output force, the sensitivity determining the reiationship betvveen the appiied machine output force and the sensor input forceaccording to a predefined aigorithni or function using increasing sensor measurement vaiues continuousiy obtained from the at iaast one sensor means during the gripping niovemeitt so that tha adjusted or recaicuiated appiied machine output force as a function of increasing sensor measurement vaiues above the iovvest threshoid sensor input force yieiding a ntaxirnunt output force is substantiaiiy constant and corresponds, or substantiaiiy to the maximum force appiied for the gripping movement, therehy a taiiing sensor rrieasurement vaiue obtained from the force detecting sensor means indicating an intention by the human hand or finger to reiease a grasp foiiovvirig the gripping movement vvouid resuit in an appiied machine output force that is tower than the maximum machine output force appiied for the gripping movement. ln embodiments, the recaicuiating step of the method according to the technology disclosed is comprising dynarnicaiiy recaicuiating, hy the contrci syfstemlfdevice and in response to determining that obtained sensor measurement vaiues are above a certain sensor input force vaiue which is the iovvest sensor input force vaiue yieiding a maximum output force, the sensitivity determining the reiationship hett/trean the appiied machine output force and the sensor input force using the foiiovring formuia vvhicii is appiicabie oniy for sensor iripiit force tfaiues greater than a iowest sensor input force vaiue yieiding a maximum output force for the gripping movement: urherein Smdynamic is the recaicuiated sensitivity pararnetar vaiue deterniining the machine output force as a function of a detected sensor input force above the certain sensor input force vaiue, Rsensorthreshoid is the threshoid sensor input forca vaiue heiow vrhich no machine output force is appiied, fïserisorrnax is the maximum sensor input force detected for the grippiiig movement, Rsensorrttâaturation is the currentiy detected sensor input force tfaiue higher titan a ton/est sensor input force vaiue yieiding a rnaximurn machine output force for the gripping rnoirement, and Swdefauit is the defauit sensitivity parameter vaiue determining an increased machine output force response as a function of an increasing sensor input force ahove the threshcid sensor input force vaiue and oeicvir said certain sensor input force vaiue, and vvhich is typicaiiy set by the user of the giove.

BRIEF DESCRIPTION OF DRAWINGS Preferred embodiments of a strengthening glove and control system according to the technology disclosed will be described more in detail below with reference to the accompanying drawings wherein:ln the following, the technology disclosed will be described in detail, with reference to exemplifying embodiments and to the enclosed drawings, wherein: Figure 1 is a perspective view of a strengthening glove according to an example embodiment of the technology disclosed, worn by a human hand and comprising a control system; Figure 2 is a perspective view of a strengthening glove according to another second example embodiment of the technology disclosed, worn by a human hand and further showing sensor means; Figure 3 is a flowchart illustrating a method according to the technology disclosed; Figure 4 illustrates an example of the machine output force applied as a function of the detected sensor input force.

Figure 5a illustrates a prior art example of the machine output force applied by the actuating means of a strengthening glove as a function of the sensor input forces detected by a sensor means; Figure 5b illustrates a prior art example of the sensor input force detected by a sensor means and the machine output force applied by the actuating means of a strengthening glove over time during a gripping movement and the release of grasp of the gripping movement; Figure 5c illustrates an example embodiment of the technology disclosed for the machine output force applied by the actuating means of a strengthening glove as a function of the sensor input forces detected by a sensor means; and Figure 5d illustrates an example embodiment of the technology disclosed for the sensor input force detected by a sensor means and the machine output force applied by the actuating means of a strengthening glove over time during a gripping movement and the release of grasp of the gripping movement.

DETAILED DESCRIPTION ln the drawings, similar details are denoted with the same reference number throughout the different embodiments. ln the various embodiments of the strengthening glove and control system according to the technology disclosed, the different subsystems are denoted. The "boxes"/subsystems shown in the drawings are by way of example only and can within the scope of the technology disclosed be arrangedin any other way or combination. ln the drawings, similar details are denoted with the same reference number throughout the different embodiments.

The technology disclosed relates to a strengthening glove, or force-assisting glove, in other words a glove arranged to be worn by a human hand and used for strengthening a gripping movement executed by one or more fingers of the hand. The technology also relates to a feedback control system for a strengthening glove, and methods for operating such a strengthening glove. ln particular, the technology disclosed relates to a strengthening glove and control system for dynamic control of the glove, and methods for dynamic control of a strengthening glove.

The technology disclosed relates to a strengthening glove with at least one glove finger and comprising a control system arranged to strengthen a movement, e.g. a gripping movement, performed by a human hand wearing the strengthening glove.

The control system comprises at least one sensor means with at least one sensor arranged to detect, in at least one measurement location on the palm of the hand and the palm side of the at least one glove finger, a respective force between a respective human finger wearing the respective glove finger and a respective contact surface onto which the gripping movement is applied.

The control system of the strengthening glove further comprises at least one actuator, or actuating means, arranged to impart a force to a respective at least one of the glove fingers. The control system may further comprise a control device arranged to read respective sensor measurement values from the at least one sensor means for each of the at least one measurement location.

The at least one sensor means is typically arranged on at least one of the palm of the hand and the palm side of the at least one glove finger of the strengthening glove and is configured to detect a respective pressure or force between a respective human finger wearing the respective glove finger and a respective contact surface onto which a gripping movement is applied.

The technology disclosed is partly based on the insight that the machine output force applied to the respective at least one glove finger by the control system via its actuators is in response to, or a function of, the sensor measurement values of the pressure or force detected by the force detecting sensor means and not the manual force imparted by the user alone.The inventors have identified a need to improve the control of the machine output force applied by the actuating means of the glove by providing a more suitable machine output force response for the intention by the user of the glove to release a grasp following a gripping movement.

This objective is achieved by recalculating, the sensitivity or relationship betvveen the sensor input force detected by the sensor means and the machine output force applied by the actuating means of the glove for the release of a grasp compared to the gripping movement, e.g. in response to detecting a current sensor input force that yields a maximum output force applied.

The inventors have further realized that the range of detected sensor measurement values and thereby the magnitude of the applied machine output force may depend on the different nature of the various tasks performed by the strengthening glove, the sensor technology used for the sensors and the physical and electrical properties of the individual sensors.

Moreover, the inventors have also realized that the range of detected sensor measurement values and thereby the applied machine output force continuously change over time when the electrical properties of the individual sensors and the mechanical properties of the individual gloves change, including the aging of the gloves and their sensors.

The problems with prior art strengthening gloves therefore include that the properties of the strengthening gloves typically vary over time and between individual strengthening gloves, and, in particular, that the release of a grasp require a suitable sensitivity and machine output force that is different from the sensitivity of the gripping movement.

Thus, according to the technology disclosed, the applied machine output force during the release of a grasp will be different than the machine output force applied for the gripping movement.

According to aspects of the technology disclosed, the control system is configured to use a separate algorithm/function for the sensitivity during release of a grasp and/or dynamically recalculate the relationship between the sensor input force detected by the at least one sensor means and the machine output force applied to the respective at least one glove finger via at least one actuating means for an ongoing gripping movement, where the relationship is dynamically adjusted or recalculated in response to determining, by the centret sgvstent, that the senser measurement values currentiy ehtained frem the at least ene eenser means is higher than a sensor input force vfatue that yfieids a maximum machine output force eppiied for the gripping ntevemeht. ln order to provide a more suitable machine output force response to the intention by the user to release a grasp, the technology disclosed proposes to dynamically recalculate the sensitivity in response to detecting that the currently detected sensor input force is yielding a maximum output force applied for the gripping movement. ln embodiments, a dynamic sensitivity algorithm may be used by the control system of the glove to ensure that a sensor lower input force detected following the release of a grasp will always result in a lower machine output force applied.

When the glove calculates the machine output force, or required tendon tension, in response to a sensor input force, a sensitivity parameter is typically factored in to determine how much assistance, or machine output force, the glove should provide. The sensitivity parameter is typically configurable. With a high sensitivity setting the machine output force applied reaches the maximum machine output force for a gripping movement even for small sensor input forces. A consequence of this is that when the user starts releasing a grasp, the glove would not respond to the lowered sensor input force detected, instead the applied machine output force will remain at the maximum machine output force for the gripping movement. To prevent this, a dynamic sensitivity algorithm may be used to ensure that a sensor lower input force detected following the release of a grasp will always result in a lower applied machine output force. ln embodiments of the technology disclosed and if the detected sensor input force on a fingertip force sensor is higher than the force that would yield the maximum machine output force applied given the configured sensitivity, a lower sensitivity is recalculated which makes the current sensor input force correspond to, or yield, the maximum machine output force for the gripping movement. This means that when a lower sensor input force is detected following the release of a grasp by the user, a lower machine output force than the maximum output force will be applied. The sensitivity is typically calculated and recalculated separately for each glove finger.

The technology disclosed also relates to a method for operating a strengthening glove with at least one glove finger, which glove is arranged to strengthen a gripping movement performed by a human hand wearing the glove, which glove comprises at least one force detecting sensor means arranged to detect, in at least one measurement location on the palm of the hand or the palm side of the at least one glove finger, a respective force between a respective human finger wearing the respective glove finger and a respective contact surface onto which the gripping movement is applied.The strengthening glove further comprises at least one actuating means arranged with at least one actuator to impart a force to a respective one of the glove fingers, so that the corresponding human finger wearing the glove finger in question is bent towards a gripping position.

The strengthening glove of the technology disclosed further comprises a control device, arranged to read a respective measurement value from the sensor means for each of the measurement locations and to control the respective force applied by the at least one actuating means using a force strengthening feedback loop based upon the sensor measurement values.

The technology disclosed addresses these problems by providing a strengthening glove and a control system for adaptive control using, for example, softvvare programs and/or algorithms initiated using sensor measurement values and input from the same sensor locations that are used in a feedback loop in order to perform the strengthening action of the glove, as well as a method implementing such functionality. ln embodiments, the strengthening glove and control system is configured to dynamically and automatically adjust and control, for the release of a grasp following a gripping movement, the relationship between the machine output force for the respective at least one glove finger and the at least one sensor input force. The relationship between the machine output force for the respective at least one glove finger and the at least one sensor input force may then be adjusted in response to the control system identifying that the currently detected sensor input force yields a maximum machine output force for the gripping movement. ln embodiments, the control system, is configured to determine the machine output force applied to the respective at least one glove finger by at least one of the at least one actuating means, wherein the machine output force applied to the respective at least one glove finger for the release of a grasp following a gripping movement is determined by the control system based on sensor measurement values read from the at least one sensor means during the gripping movement. ln embodiments, the method further comprising determining, by the control device, the machine output force applied to the respective at least one glove finger by at least one of the at least one actuating means, wherein the machine output force applied to the respective at least one glove finger for the release of a grasp following a gripping movement is determined based on sensor measurement values read from the at least one sensor means during the gripping movement.ln different embodiments, the dynamically and automatically adjusted and controlled relationship may include parameter values or a function determining the down-ramp function determining the decreasing machine output force applied via the at least one actuating means as a function of decreasing sensor input force detected during the release of a grasp. ln embodiments, a recalculation of the relationship between the detected at least one sensor input force and the machine output force applied to the respective at least one glove finger, e.g. parameter values for controlling the applied machine output force, may be determined by the software and algorithms of a glove-external control system based on sensor measurement data obtained by the at least one sensor means of the glove during the gripping movement. ln certain aspects, the technology disclosed relates to improvements in the firmware regarding algorithms which detect the user's intentions of releasing a grasp to be able to respond quickly to the user's intentions. The strengthening glove of the technology disclosed typically consists of a glove with artificial tendons running through ducts or sown into the fingers, which are connected to a power unit.

The power unit contains actuators which pull on the artificial tendons to strengthen a movement imparted by the user, e.g. a gripping movement. When the system is in the starting state the actuators are typically at the end position which give the maximum slack of the artificial tendons. This will be referred to as the lower end position. As the actuators move to tighten the tendons, they move in the positive direction. This of course typically implies a positive rotation of the motors, in response to a positive applied voltage.

The strengthening glove according to the technology disclosed is equipped with at least one sensor means including, e.g., pressure sensors, force sensors and/or strain sensors arranged in the glove fingers. The sensor means are used to sense the sensor input force when the user grasps an object and, when the glove is providing assistance, the combined grasping force of the user and the machine output applied by the control system via its actuating means. ln embodiments, the adaptive sensitivity introduced by the technology disclosed may enable the automatic adjustment of at least one parameter value determining a relationship between the machine output force applied and the detected sensor input force which is determined based on sensor measurement values obtained during at least one previous gripping movement and which are reflecting the intention of the user wearing the strengthening glove during that previous gripping movement.ln embodiments, the adjustment of the at least one parameter value determining the relationship between the machine output force applied and the sensor input force for the release of a grasp following a gripping movement based on sensor measurement values read or obtained during the gripping movement.

The strengthening glove and the control system of the technology disclosed may be configured to learn within which sensor input force values to operate and apply a machine output force via the at least one actuating means. The strengthening glove and the control system may also be configured to adaptively adjust or change the threshold sensor input force xfeiue below which no machine output force ie applied, the iovvest sensor input force value yfieioing e maximum machine output force for the gripping movement and/or the maximum machine output force applied for the next gripping movement based on already obtained and stored sensor measurement values, e.g. based on the range of sensor measurement values detected for the at least one sensor input force and which are obtained for at least one previous movement, e.g. gripping movement. The sensitivity of the strengthening glove during the release of a grasp may then be determined by the control system based on the adjusted or changed activation threshold value, saturation threshold value and/or the maximum machine output force, e.g. by using a separate sensitivity algorithm and/or recalculating the sensitivity based on the adaptively adjusted or changed activation threshold value, saturation threshold value and/or the maximum machine output force.

As mentioned above, the at least one sensor means are used to sense or detect the sensor input force or pressure when the user grasps an object and, when the glove is providing assistance, the combined grasping force of the user and the system. According to embodiments of the technology disclosed, the relationship betvveen the machine output force and the sensor input force for the release of a grasp following a gripping movement may in addition and at least partly be determined based on the sensed or detected sensor input force when the user grasped an object during at least one previous gripping movement and, when the glove was providing assistance, the sensed or detected combined grasping force of the user and the system during the release of at least one previous gripping movement. ln embodiments, the strengthening glove and control system of the technology disclosed may learn about the intentions and behaviour of the user of the glove and, based on sensor measurement values obtained during at least one previous gripping movement, automatically adjust within which range of sensor input force to apply a machine output force via the actuating means. The control system may also be configured to automatically adjust the magnitude of the applied machine output force, including the maximum machine output force, based on previously obtained sensor measurement values for thesensor input force. The range of obtained sensor measurement values for the sensor input force may be affected by many factors including the varying nature of the tasks performed (e.g. gripping movement tasks), the response sensitivity of the at least one sensor of the at least one sensor means, the type of protective glove used and the anatomy of the hand of the user wearing the strengthening glove. According to embodiments of the technology disclosed, the relationship betvveen the machine output force and the sensor input force for the release of a grasp following a gripping movement may in addition and at least partly be determined based on the sensed or detected sensor input force when the user grasped an object during at least one previous gripping movement and, when the glove was providing assistance, the sensed or detected combined grasping force of the user and the system during the release of at least one previous gripping movement.

The varying nature of the tasks performed which determines the range of obtained sensor measurement values for the sensor input force include that some tasks during certain periods involve application of significantly higher forces to properly execute the tasks, while for other tasks the force range is lower and/or smaller. The response sensitivity of the at least one sensor, i.e. the magnitude of the electrical signal generated by the sensor in response to the pressure or force applied to the sensor, may depend on the sensor technology used and the physical and electrical properties of the individual sensor unit used, including that the response sensitivity of the sensors typically decreases over time. Moreover, different protective gloves have different physical and mechanical properties, which leads to that the force transmission through the protective glove may vary that, in turn, typically causes the sensor input force range to vary with the type of protective glove used. A thick and hard glove generally gives a low sensor input range. All of the above factors may have an impact on the range of sensor measurement values obtained during a gripping movement which, in turn, impact the adaptive control and the determining of the relationship between the machine output force and the sensor input force, e.g. the determining of the machine output force as a function of the sensor input force.

All of the above-mentioned factors may thus have an impact on the sensor measurement values obtained during the previous at least one gripping movement and on which the determining of the relationship between the machine output force applied and the sensor input force detected is based upon.

Example embodiments of the strengthening glove according to the technology disclosed may use custom-made tension sensors to measure the tension in the artificial tendons. However, in other embodiments of the technology disclosed, these tension sensors are replaced by a model-based estimation of the tension in the artificial tendons. The use of a model-based estimation of the tension in the artificial tendons typically lead to significant cost reductions as well as increased robustness of the system.

The dynamic sensitivity introduced by the technology disclosed, where adjustments of the relationship between the machine output force applied and the detected sensor input force is based on read or obtained sensor measurement data indicating the will of the user wearing the strengthening glove during release, may typically also have a longer time horizon.

The strengthening glove and the control system of the technology disclosed may then be able and configured to learn within which sensor input force values to operate and apply a machine output force to the respective at least one glove finger via the at least one actuating means during release of a grasp, but may also be configured to adjust or change the activation threshold value, the saturation threshold value and/or the maximum machine output force applied for the next gripping movement based on the range of sensor measurement values detected for the at least one sensor input force and which are obtained for a plurality of previous movements, e.g. gripping movements.

As an example, the machine output force applied to the respective at least one glove finger via the at least one actuating means during release of a grasp as a function of read sensor measurement values may be determined based on several previously determined ranges of sensor measurement values for the at least one sensor input force, activation threshold values, saturation threshold values and/or the maximum machine output force applied for a plurality of previous gripping movements performed over a longerpenod.

As an example embodiment, the strengthening glove and the control system of the technology disclosed may then be able and configured to learn a behaviour of the user of the glove and continuously update or adjust, for the next gripping movement, an algorithm or function determining the relationship between the machine output force applied to the respective at least one glove finger via the at least one actuating means during release of a grasp as a function of read sensor measurement values.

All figures share the same reference numerals for similar or corresponding parts.

Figure 1 illustrates a human hand 10 wearing a strengthening glove 100 according to an embodiment of the technology disclosed. The strengthening glove 100 comprises a control system 200, also according to the technology disclosed.Furthermore, the glove 100 comprises at least one glove finger. ln figure 1, five glove fingers 101 -105 are illustrated, for exemplifying purposes. The glove 100 is arranged to strengthen a movement, e.g. a gripping movement, performed by the human hand 10 wearing the glove. The control system 200 also comprises at least one actuating means 240 (generally indicated in figure 1), arranged to impart a force to a respective one of the glove fingers 101-105. The actuating means 240 in this example embodiment is arranged on the top of the arm/hand. ln other embodiments of the technology disclosed, the actuating means 240 may be arranged in other locations such as on the back of the user or on the inside of the user's arm (Figure 2).

Figure 2 illustrates a human hand 10 wearing a strengthening glove 100 according to another example embodiment of the technology disclosed. Figure 2 shows the sensor means 210 arranged on the palm side of the glove fingers. ln the example embodiment illustrated in Figure 2, the actuating means 240 is arranged on the inside of the user's arm. ln order for the glove 100 and control system 200 to be able to control the machine output force of at least one actuating means 240 using a force strengthening feedback loop, the control system 200 comprises at least one sensor means 210 arranged to detect, in at least one measurement location on the palm 106 side of the at least one glove fingers 101-105, a respective force between a respective human finger 11-15 wearing the respective glove finger 101-105 and a respective contact surface onto which the gripping movement is applied, at the respective at least one measurement location for the sensor means 210. ln different example embodiments of the technology disclosed, several measurement locations may be arranged on the palm side of the hand, on one single finger and/or on different fingers.

The control system 200 according to the technology disclosed also comprises at least one actuating means 240 (generally indicated in figure 1), arranged to impart a force to a respective one of the glove fingers 101-105, so that the movement imparted by the corresponding human finger 11-15 wearing the glove finger 101-105 is strengthened in its movement, e.g. gripping movement. ln the figures, one and the same actuating means 240 is arranged to impart respective such forces to each one of the five fingers 101-105. However, it is realized that according to different embodiments of the technology disclosed, several actuating means may be used in parallel, for instance each operating on one finger each, and/or there may be less than five controlled glove fingers 101-105. More than one actuating means 240 may also operate on one single finger, such as one actuating means 240 being arranged to extend or open the glove finger 101-105 and one actuating means 240 being arranged to strengthen a movement imparted by the finger in question. A combination of the above is also possible.The control system 200 is arranged to read a respective sensor measurement value from the at least one sensor means 210 for each of the at least one measurement location, and to apply a machine output force to the respective at least one glove finger 101-105 via the actuating means 240 as a function of read or obtained sensor measurement values.

According to the technology disclosed, the control system 200 may be further configured to determine and/or control the relationship betvveen a sensor input force detected by the at least one sensor means 210 and the machine output force applied to the respective at least one glove finger 101-105 by the at least one actuating means 240. The control system 200 is configured to determine and/or control, for the release of a grasp following a gripping movement, the machine output force applied to the respective at least one glove finger 101-105 by the at least one actuating means 240 as a function of read sensor measurement values.

The control system 200 may then typically be arranged to read or obtain a respective sensor measurement value from the at least one sensor means 210 for each of the at least one measurement location during a gripping movement, and to determine and/or control the respective machine output force applied to the respective at least one glove finger 101-105 via the actuating means 240 to each controlled finger 101-105 during the release of a grasp following a gripping movement. ln embodiments, the control system 200 may typically comprise a control device 230, connected to the actuating means 240. As such, the control device 230 may comprise, or has access to, operating logic defining means for controlling the machine output force of the at least one actuating means as a function using a force strengthening feedback loop. For instance, such logic may be implemented in mechanics comprised in the control device 230, but preferably the control device 230 comprises electronic hardware circuitry and/or, preferably, a digital processor programmed with software configured for determining the relationship between a sensor input force detected by the at least one sensor means 210 and the machine output force of the at least one actuating means, including determining the relationship during the release of a grasp following a gripping movement.

To be specific and in embodiments, the control device 230 may typically be arranged to read a respective sensor measurement value from the at least one sensor means 210 for each of the at least one measurement location during at least one gripping movement, and to control the respective machine output force applied via the actuating means 240 to each controlled finger 101-105 as a function of read sensor measurement values. The at least one sensor means 210 may then be connected to the control device 230, for instance via electric cables (not shown in the figures).The actuating means 240 may be conventional as such, for instance strengthening finger 11-15 movement via artificial tendons 250 (see below), pulling on the glove 100 fingers 101 -105, by pulling the artificial tendons 250 via an electrical motor.

Hence, the control may be performed using a software program, which comprises or is constituted by a force strengthening feedback loop, in turn based upon the sensor measurement values as input parameters. ln other words, the control device 230 receives current sensor measurement values, performs calculations with these values as input parameters, and controls the actuating means 240 based upon output values of the calculations so as to achieve and apply a machine output force effectively strengthening or amplifying a gripping motion performed by the hand 10 wearing the glove However, according to embodiments of the technology disclosed, the control device 230 of the control system 200 may be further arranged to adjust, for the release of a grasp following a gripping movement, the machine output force applied by the at least one actuating means as a function of the sensor input force detected by the at least one sensor means. lt is important to understand that the term "software program" herein refers to the algorithm used to, based upon read sensor means 210 measurement values, calculate control data for controlling the actuating means 240, as opposed to the actual current control state fed to the actuating means 240. For example, merely the fact that a particular glove 100 finger 101-105 at a particular instant is bent with, say, a force of 1/10 N, as the corresponding finger 11-15 is currently pressed against a particular surface, does not constitute a "software program" in the present sense. lnstead, a "software program" rather prescribes how to calculate an appropriate machine output force (or any other actuating means control parameter) based upon a given set of sensor measurement values/data from the sensor means 210, producing variable control parameters based upon variable sensor input data, according to a certain set of logical rules. Hence, under one particular software program, different actuating means control will typically result based upon different sensor input detected by the at least one sensor means Herein, the term "measurement location" refers to a location where the said force is measured using the sensor means 210. Such a measurement location may be point-like or have a certain surface extension.According to embodiments, the sensor measurement values from the at least one measurement location are used as an input parameter into a control program. ln embodiments, all measurement locations are such measurement locations, being used in the control program.

According to embodiments of the technology disclosed, the control system is further configured to adjust, for the release of a grasp following a gripping movement, the relationship between the sensor input force and the machine output force. For instance, in order for the control system 200 to dynamically control the relationship between the sensor input force and the machine output force, in addition to the sensor measurement values obtained from the at least one sensor means 210 during a gripping movement, the control device 230 is further configured to sense one or several particular glove 100 fingers 101-105 to be in a respective particular predetermined position or angle.

The technology disclosed provides for a glove 100 which provides more efficient and more suitable aid and user experience during the release of a grasp than has previously been the case. lt is realized that the sensor means 210 may be in the form of one and the same sensor, e.g. pressure sensor or force sensor, arranged to measure pressure and/or force at several such locations8, even along a continuous surface, of the glove 100 fingers 101-105. However, it is preferred that the sensor means 210 comprises at least one distinct sensor, e.g. at least one pressure sensors and/or force sensors, in turn arranged at the respective measurement locations and connected to a central processing unit, or directly to the control device 230. ln the figures, the sensor means 210 comprises one such respective sensor for each measurement location.

Preferably, the above-mentioned control program is arranged to implement the feedback loop as described above, possibly in a way which is conventional as such. ln another preferred embodiment, the control program comprises applying a machine output force to at least one glove 100 finger 101- ln the embodiment illustrated in Figure 1, the actuating means 240 operating on at least one glove 100 finger 101-105 comprises a respective artificial tendon 250 connected to the glove 100 finger 101-105, at respective fastening points, which artificial tendon 250 is arranged to strengthen a movement imparted by the respective finger 101-105 by the control device 230 applying, via the machine output force applied by the actuating means 240, a respective pulling force to the respective artificial tendon 250 and as a result also to the respective glove finger 101-105. The control device may comprise a power unit (not shown) and the artificial tendon can be attached to the control device 230, e.g. the power unit, via conventional Bowden cables 330. ln embodiments, the actuating means 240 may comprise a mechanism such as a linear or circular actuator, e.g. linear nut and screw or circular bobbin, which is used to impart the pulling force and to adjust the length of the artificial tendon Figure 3 i||ustrates the method steps of a method according to embodiments of the technology disclosed for operating a strengthening glove 100 of the type described above. ln a preferred step 301, the control device 230 obtains the measurement values from at least one of the at least one sensor means 210 during a gripping movement. ln a step 302, the control device 230 determines that the sensor nieasurenient vaiues currentiy obtained from a force deteotirig sensor means is iiigher than a certain sensor input force tfaiue that is the iowest sensor input force veiue that yieios the maximum niaciiiite output force appiieo for the gripping movement. ln a step 303 and following the determining in step 302 that the that the sensor measurement vaiues currentiy obtained from a force detecting sensor rneans is higher than a certain sensor input force vaiue that is the iowest sensor input force vaiue that yieios the maximum niachiite output force apoiied for the gripping movement, the oontroi system adjusts e sensitivity pararneter vaiue determining the machine otitout force apoiieo as a function of the sensor measurement vaiues obtained from the at ieast one SêiiSOi' iiiššêiiâ ln a step 304, the control device 230 is controlling, for the release of a grasp following a gripping movement, the machine output force applied via the at least one of the at least one actuating means 240 in accordance with the, in step 303, adjusted relationship between the sensor input force detected and the machine output force applied. The relationship between the sensor input force detected and the machine output force applied is then typically dynamically and continuously adjusted only during the release of the gripping movement in that the relationship between the sensor input force detected and the machine output force applied is again adjusted and changed in accordance with a sensitivity function for the up-ramp for the next gripping movement. ln example embodiments, the control system may be configured to, during or following the completion of the release of a gripping movement, automatically re-adjust the relationship so that relationship between the sensor input force detected and the machine output force applied for the up-ramp for the next gripping movement is in accordance with a sensitivity function that corresponds to the sensitivity function for the previous (immediately preceding) gripping movement. Hence, after completion of the release of the gripping movement, the sensitivity, orsensitivity function, applied by the control system for the next up-ramp typically returns to the sensitivity (function) used for the up-ramp of the previous gripping movement.

Hence, the control device 230 of the control system 200 causes the actuating means 240 to be controlled according to the determined relationship in step 303, thereby the strengthening glove 100 and its control system 200 is configured to dynamically adjust and control the relationship betvveen the sensor input force detected by at least one of the at least one sensor means 201 and the machine output force applied via the actuating means Figure 4 illustrates an example of the machine output force applied by the actuating means of a strengthening glove as a function of the sensor input force(s) detected by the sensor means of the strengthening glove, i.e. the relationship between the at least one sensor input force detected by the at least one sensor means and the machine output force applied to the respective at least one glove finger by the at least one actuating means. "T - Output" on the y-axis is the applied machine output force and "F - lnput" on the x-axis is the detected sensor input force. Thus, an obtained at least one sensor measurement value for the sensor input force F - Input will result in an applied machine output force T - Output.

"T_max" in Figure 4 is maximum machine output force applied, "dz" is the threshold value for the sensor input force below which no machine output force is applied and "s" is the slope of the curve or up-ramp defining the sensitivity of the strengthening glove, i.e. the relationship between the sensor input force detected and the machine output force applied by the control system via its actuating means above the threshold value dz but below a lowest sensor input force when a maximum machine output force is applied. ln the example illustrated in Figure 4, the machine output force applied is a linear function of the sensor input force in the sensor range between the threshold value dz which is the highest sensor value when no machine output force is applied and below a lowest sensor input force when a maximum machine output force is applied. However, in other examples, the machine output force applied by the actuating means of a strengthening glove may be a non-linear function of the sensor input force detected in the sensor range between the threshold value dz and the lowest sensor input force for which a maximum machine output force T_max for the gripping movement is applied.

Figure 5a illustrates a prior art example of the machine output force applied by the actuating means of a strengthening glove as a function of the sensor input forces detected by a sensor means.Figure 5a illustrates a prior art example of the machine output force applied by the actuating means of a strengthening glove as a function of the sensor input force(s) detected by the sensor means of the strengthening glove, i.e. the relationship betvveen the at least one sensor input force ("F - lnput") detected by the at least one sensor means and the machine output force applied ("T - Output") to the respective at least one glove finger by the at least one actuating means. ln Figure 5a, the up-ramp 501 illustrates an applied machine output force that increases linearly with the detected sensor input force until it reaches a sensor input force yielding a maximum machine output force T_max, i.e. a saturation level. The down-ramp 502 in Figure 5a illustrating the release of a grasp follows the same curve/function as the up-ramp 501. ln this prior art, the intention of the user of the glove to release a grasp will result in a delayed decreased applied machine output force because a detected decreased sensor input force will still result in a maximum machine output force applied until the sensor input force detected is lower than the lowest sensor input force yielding a maximum machine output force for the gripping movement.

Figure 5b illustrates a prior art example of the sensor input force detected by a sensor means and the machine output force applied by the actuating means of a strengthening glove over time during a gripping movement and the release of grasp of the gripping movement.

Figure 5b illustrates substantially the same prior art example and delayed response as illustrated Figure 5a. ln Figure 5b, the curve 503 shows the applied machine output force during the gripping movement and the release of the grasp of the gripping movement over a time period and the curve 504 shows the detected sensor input force during the same gripping movement and the release of the grasp of the same gripping movement and over the same time period. When the control system detects a decreased sensor input force following release of a grasp, the response is delayed in that the applied machine output force is still the maximum machine output force applied for the gripping movement during the delay.

Figure 5c illustrates an example embodiment of the technology disclosed for the machine output force applied by the actuating means of a strengthening glove as a function of the sensor input forces detected by a sensor means; and Figure 5c illustrates an example embodiment of the technology disclosed where the machine output force applied by the actuating means of a strengthening glove is a function of the sensor input force(s) detected by the sensor means of the strengthening glove, i.e. the relationship between the at least onesensor input force ("F - lnput") detected by the at least one sensor means and the machine output force applied ("T - Output") to the respective at least one glove finger by the at least one actuating means. ln the embodiment of the technology disclosed illustrated in Figure 5c, the up-ramp 505 illustrates an applied machine output force that increases linearly with the detected sensor input force until it reaches a sensor input force yielding a maximum machine output force T_max, i.e. a saturation level. The down- ramp 506 in Figure 5c illustrating the release of a grasp follows a different linear function than the up- ramp 505. The down-ramp 506 follows a linear function from the current sensor input force detected for the grasp until the detected sensor input force reaches a threshold value "dz" for the sensor input force below which no machine output force is applied. ln the example embodiment illustrated in Figure 5c, the intention of the user of the glove to release a grasp from the currently detected sensor input force will instantly result in a decreased applied machine output force according to the dynamically recalculated/adjusted relationship between the at least one sensor input force ("F - lnput") detected by the at least one sensor means and the machine output force applied ("T - Output"). For the down-ramp 506, the machine output force applied decreases continuously with decreased sensor input force values detected until the detected sensor input force reaches a threshold value "dz" for the sensor input force below which no machine output force is applied.

Figure 5d illustrates an example embodiment of the technology disclosed for the sensor input force detected by a sensor means and the machine output force applied by the actuating means of a strengthening glove over time during a gripping movement and the release of grasp of the gripping movement.

Figure 5d illustrates substantially the same example embodiment of the technology disclosed as illustrated in Figure 5c. ln Figure 5d, the curve 507 shows the applied machine output force during the gripping movement and the release of the grasp of the gripping movement over a time period and the curve 508 shows the detected sensor input force during the same gripping movement and the release of the grasp of the same gripping movement and over the same time period. When the control system detects a decreased sensor input force following release of a grasp, the user of the glove experiences an instant response to the intention to release the grasp in that the detected decreased sensor input force instantly results in a decreased applied machine output force. ln general, the above-described examples are freely combinable as applicable.

Hence, the invention is not limited to the said embodiments, but can be varied across the full scope of the enclosed claims.ln embodiments, the control system is further configured to determine and store the range of obtained sensor measurement values for a plurality of previous gripping movements and adaptively determine and adjust the machine output force of the at least one actuating means as a function of the sensor input force based on the stored range of obtained sensor measurement values for the plurality of previous gripping movements. ln embodiments, the control system is further configured to determine the range of obtained sensor measurement values for the plurality of previous gripping movements by applying a lowpass filter and then determine and adjust the relationship between the sensor input force and the machine output force applied to the respective at least one glove finger via the at least one actuating means for the next gripping movement based on the determined range of sensor measurement values. ln embodiments, the control system is further configured to adaptively determine and adjust, for the next gripping movement, the activation threshold value for the sensor input force below which no machine output force is applied to the respective at least one glove finger by the at least one actuating means, and wherein the activation threshold value is determined based on sensor measurement values read from the sensor means during at least one previous gripping movement. ln embodiments, the control system is further configured to adaptively determine, for the next gripping movement, the maximum machine output force applied by at least one of the at least one actuating means, and wherein the maximum machine output force applied is determined based on sensor measurement values read from the at least one sensor means during at least one previous gripping movement. ln embodiments, the control system is further configured to store sensor measurement values obtained during a plurality of previous gripping movements and automatically determine and adjust the relationship betvveen the sensor input force and the machine output force to be applied to the respective at least one glove finger based on the stored sensor measurement values obtained during a plurality of previous gripping movements.

The control system may then use the adjusted relationship between the sensor input force detected by the at least one sensor means and the machine output force applied for the next or subsequent gripping movement and, during the next or subsequent gripping movement, dynamically adjust the relationship betvveen the sensor input force detected by the at least one sensor means and the machine output force applied in response to determining that the current sensor measurement values for the sensor input force yields a maximum machine output force, thereby providing an improved response sensitivity (i.e. a decreasing machine output force below the maximum machine output force) for decreasing sensor input values reflecting the intention by the user of the glove to release the grasp of the gripping movement. ln aspects, the technology disclosed relates to a method for operating a strengthening glove with at least one glove finger, which glove is arranged to strengthen a gripping movement performed by a human hand wearing the glove, which glove comprises at least one sensor means arranged to detect, in at least one measurement location on the palm of the hand and/or the palm side of the at least one glove finger, a respective force between a respective human finger wearing the respective glove finger and a respective contact surface onto which the gripping movement is applied, which glove further comprises at least one actuating means arranged to impart a force to a respective at least one of the glove fingers, which glove further comprises a control device, arranged to read respective sensor measurement values from the at least one sensor means for each of the at least one measurement location and to control the respective machine output force applied by the at least one actuating means using a force strengthening feedback loop based upon the sensor measurement values, wherein the method, in addition to dynamically adjusting/recalculating the sensitivity in response to determining that currently obtained sensor measurement values yield a maximum machine output force for a gripping movement, further comprises the steps of a) reading, by the control device, sensor measurement values from the at least one sensor means during at least one gripping movement; b) determining, by the control device and for the next gripping movement, the relationship between the sensor input force detected by the at least one sensor means and the machine output force to be applied to the respective at least one glove finger by the at least one actuating means based on the sensor measurement values read from the at least one sensor means during the at least one gripping movement; and c) controlling, by the control device and for the next gripping movement, the machine output force applied to the respective glove finger by at least one of the at least one actuating means, wherein the applied machine output force is in accordance with the determined relationship between the sensor input force detected and the machine output force. ln embodiments, the method further comprising storing, by the control device, sensor measurements values obtained during the at least one previous gripping movement, and automatically determining and adjusting, for the next or subsequent gripping movement and based on the stored sensor measurement values, the relationship between the sensor input force detected by the at least one sensor means and the machine output force applied to the respective glove finger. The method may then further comprise that the control system uses the adjusted relationship between the sensor input force detected by the atleast one sensor means and the machine output force applied for the next or subsequent gripping movement and the method further comprises dynamically adjusting, by the control system and during the next or subsequent gripping movement, the relationship betvveen the sensor input force detected by the at least one sensor means and the machine output force applied in response to determining that the current sensor measurement values for the sensor input force yields a maximum machine output force, thereby providing an improved response sensitivity (i.e. a decreasing machine output force below the maximum machine output force) for decreasing sensor input values reflecting the intention by the user of the glove to release the grasp of the gripping movement. ln embodiments, the method further comprising adjusting, by the control device and for the next or subsequent gripping movement, the slope of the up-ramp determining the increasing machine output force applied by the at least one actuating means as a function of increasing sensor input force detected by the at least one sensor means, wherein the up-ramp slope is determined based on sensor measurement values read from the at least one sensor means during the at least one previous gripping movement. ln embodiments, the method further comprising determining, by the control device, the range of obtained sensor measurement values for a plurality of previous gripping movements, and adaptively adjusting, by the control device and for the next or subsequent gripping movement, the slope or function of the up-ramp determining the increasing machine output force applied to the respective at least one glove finger as a function of increasing sensor input force detected by the at least one sensor means for the next gripping movement, where the determining of the slope or function is based on the range of obtained sensor measurement values for the plurality of previous gripping movements. ln embodiments, the method further comprising determining, by the control device, the range of obtained sensor measurement values for the plurality of previous gripping movements by applying a lowpass filter, and then adjusting, by the control device, the slope or function of the up-ramp for the respective at least one glove finger and for the next gripping movement, where the adjustment is based on the determined range of sensor measurement values. ln embodiments, the method further comprising adaptively determining, by the control device and for the next gripping movement, the maximum machine output force applied to respective at least one glove finger by at least one of the at least one actuating means, wherein the maximum machine output force applied to the respective at least one glove finger is determined based on sensor measurement values read from the at least one sensor means during at least one previous gripping movement.

Claims (8)

1. Claims A strengthening glove (100) with at least one glove finger (101, 102, 103, 104, 105) and comprising a control system (200) arranged to strengthen a gripping movement performed by a human hand wearing the strengthening glove (100) and comprises at least one sensor means (210) arranged to detect, in at least one measurement location on the palm (106) of the hand (10) and/or the palm side (106) of said at least one glove finger (101, 102, 103, 104, 105), a respective force between a respective human finger (11, 12, 13, 14, 15) wearing the respective glove finger (101, 102, 103, 104, 105) and a respective contact surface onto which said gripping movement is applied, said control system (200) further comprises at least one actuating means (240) arranged to impart a force to a respective at least one of said glove fingers (101 , 102, 103, 104, 105) and a control device (230) arranged to read respective sensor measurement values from the at least one sensor means (210) for each of said at least one measurement location, wherein said control system (200) is configured to control the machine output force of said at least one actuating means (240) using a force strengthening feedback loop based upon said sensor measurement values, and wherein said control system (200) is characterised by being further configured to, in response to determining that the sensor measurement values currently obtained from the at least one sensor means (210) are higher than a certain sensor input force value that is the lowest threshold sensor force yielding a maximum output force, recalculate the machine output force applied by at least one of the at least one actuating means (240) as a function of the sensor measurement values obtained from the at least one sensor means (210), wherein said control system (200) is configured to recalculate the machine output force applied as a function of obtained sensor measurement values so that falling sensor measurement values obtained from the at least one sensor means (210) that are above said certain lowest threshold sensor input force value yielding a maximum output force for the gripping movement and indicating an intention by the human hand (10) orfinger (11, 12, 13, 14, 15) to release a grasp result in a faster response in applying a machine output force that is lower than the maximum machine output force applied for the gripping movement. The strengthening glove (100) according to claim 1, wherein said control system (200) is configured to determine whether the sensor measurement values currently obtained from the at least one sensor means (210) is higher than a certain sensor input force value that is the lowest sensor input force value that yields a maximum machine output force applied for the gripping movement, and, in response to determining that the sensor measurement values currently obtained from the at least one sensor means (210) is higher than said certain sensor input force value, recalculate the machine output force applied by at least one of the at least one actuating means (240) as a function of the sensor measurement values obtained from the at least one sensor means (210). The strengthening glove (100) according to any of claims 1 and 2, wherein said control system (200) is further configured to dynamically recalculate the machine output force applied by at least one of the at least one actuating means (240) as a function of the sensor measurement values obtained from the at least one sensor means (210) so that falling sensor measurement values obtained from the at least one sensor means (210) indicating an intention by the human hand (10) orfinger (11, 12, 13, 14, 15) to release a grasp following the gripping movement would result in a faster response in applying a machine output force that is lower than the maximum machine output force applied for the gripping movement. The strengthening glove (100) according to any of the preceding claims, wherein said control system (200) is configured to dynamically recalculate the machine output force applied by at least one of the at least one actuating means (240) as a function of the sensor measurement values obtained from the at least one sensor means (210) so that falling sensor measurement values obtained from the at least one sensor means (210) indicating an intention by the human hand (10) orfinger (11, 12, 13, 14, 15) to release a grasp following the gripping movement would result in a decreasing machine output force also for sensor measurement values higher than said certain sensor input force value. The strengthening glove (100) according to any of the preceding claims, wherein said control system (200) is configured to dynamically recalculate the machine output force applied by at least one of the at least one actuating means (240) as a function of the sensor measurement values obtained from the at least one sensor means (210) according to a predefined algorithm so that the recalculated machine output force applied by at least one of the at least one actuating means (240) as a function of the sensor measurement values obtained from the at least one sensor means (210) is lower for sensor measurement values higher than said certain sensor input force value, the control device (230) is thereby configured to dynamically adjust the machine output force applied by at least one of the at least one actuating means (240) as a function of the sensor measurement values obtained from the at least one sensor means (210) so that falling measurement values obtained from the at least one sensor means (210) indicating an intention by the human hand (10) orfinger (11, 12, 13, 14, 15) to release a grasp following a gripping movement would result in a decreasing machine output force applied by at least one of the at least one actuating means (240). The strengthening glove (100) according to any of the preceding claims, wherein said control system (200) is configured to continuously and dynamically recalculate the machine output force applied by at least one of the at least one actuating means (240) as a function of the sensor measurement values obtained from the at least one sensor means (210) according to a predefined algorithm or function so that the continuously recalculated machine output force applied by at least one of the at least one actuating means (240) as a function of the sensor measurement values obtained from the at least one sensor means (210) keeps falling as the sensor measurement values obtained from the at least one sensor means (210) keeps rising above said certain sensor input force value, thereby the control device (230) is configured to dynamically adjust the machine output force applied by at least one of the at least one actuating means (240) as a function of the sensor measurement values obtained from the at least one sensor means (210) so that falling sensor measurement values obtained from the at least one sensor means (210) indicating an intention by the human hand (10) orfinger (11, 12, 13, 14, 15) to release a grasp following a gripping movement would result in a decreasing machine output force applied that is lower than the maximum machine output force applied for the gripping movement. The strengthening glove (100) according to any of the preceding claims, wherein said control system (200) is configured to continuously and dynamically recalculate the machine output force applied by at least one of the at least one actuating means (240) as a function of the sensor measurement values obtained from the at least one sensor means (210) according to a predefined algorithm or function using measurement values continuously obtained from the at least one sensor means (210) so that the applied machine output force as a function of increasing measurement values above said certain sensor input force value is substantially constant and corresponds to, or substantially correspond to, the maximum force applied for the gripping movement, thereby the control device (230) is configured to continuously adjust the machine output force applied by at least one of the at least one actuating means (240) as a function of the sensor measurement values obtained from the at least one sensor means (210) so that a falling measurement value obtained from the at least one sensor means (210) indicating an intention by the human hand (10) orfinger (11, 12, 13, 14, 15) to release a grasp following a gripping movement would result in an applied machine output force that is lower than the maximum force applied for the gripping movement. . The strengthening glove (100) according to any of the preceding claims, wherein said control system (200) is configured to continuously and dynamically recalculate the machine output force applied by at least one of the at least one actuating means (240) as a function of the sensor measurement values obtained from the at least one sensor means (210) S_dynamic using the following formula for sensor input force values greater than a lowest sensor input force value yielding a maximum output force for the gripping movement: S_dynamic = S_default * (F_sensorAtSaturation - F_sensorthreshold)/(F_sensormax - F_sensorthreshold) , wherein S_dynamic is the recalculated machine output force applied by at least one of the at least one actuating means (240) as a function of the sensor measurement values obtained from the at least one sensor means (210) determining the machine output force as a function of detected sensor input force above said certain sensor input force value, F_sensorthreshold is the threshold sensor input force value below which no machine output force is applied, F_sensormax is the maximum sensor input force detected for the gripping movement, F_sensorAtSaturation is the currently detected sensor input force value higher than a lowest sensor input force value yielding a maximum machine output force for the gripping movement, and S_default is determining an increased machine output force response as a function of increasing sensor input force above the threshold sensor input force value and below said lowest sensor input force value yielding a maximum machine output force. Method for operating a strengthening glove (100) with at least one glove finger (101, 102, 103, 104, 105), which glove (100) is arranged to strengthen a gripping movement performed by a human hand wearing the glove (100), which glove (100) comprises at least one sensor means (210) arranged to detect, in at least one measurement location on the palm side of said at least one glove finger (101, 102, 103, 104, 105), a respective force between a respective human finger (11, 12, 13, 14, 15) wearing the respective glove finger (101, 102, 103, 104, 105) and a respective contact surface onto which said gripping movement is applied, which glove (100) further comprises at least one actuating means (240) arranged to impart a force to a respective at least one of said glove fingers (101, 102, 103, 104, 105), which glove (100) further comprises a control device (230), arranged to read a respective sensor measurement value from the at least one sensor means (210) for each of said at least one measurement location and to control the respective machine output force applied by said at least one actuating means (240) using a force strengthening feedback loop based upon the said sensor measurement values, the method comprises the steps of: a) continuously reading, by the control system (200) and during a gripping movement, sensor measurement values obtained from the at least one sensor means (210) and for each of said at least one measurement location; the method is further characterised by: b) determining, by the control device (230), whether the sensor measurement values currently obtained from a force detecting sensor means (210) is higher than a certain sensor input force value that is the lowest threshold sensor input force value that yields the maximum machine output force applied for the gripping movement, and, in response to determining that the sensor measurement values currently obtained from the at least one sensor means (210) are higher than said certain sensor input force value: c) recalculating, by the control device (230), the machine output force applied as a function of the sensor measurement values obtained from the at least one sensor means (210), wherein the machine output force applied as a function of obtained sensor measurement values is recalculated so that falling sensor measurement values obtained from the at least one sensor means (210) that are above said certain lowest threshold sensor input force value yielding a maximum output force for the gripping movement and indicating an intention by the human hand (10) orfinger (11, 12, 13, 14, 15) to release a grasp result in a faster response in applying a machine output force that is lower than the maximum machine output force applied for the gripping movement. The method according to claim 9, wherein said recalculating step is comprising dynamically recalculating the machine output force applied by at least one of the at least one actuating means (240) as a function of the sensor measurement values obtained from the at least one sensor means (210) for sensor measurement values above said certain sensor input force value according to using a predefined algorithm or function so that the recalculated machine output force applied by at least one of the at least one actuating means (240) as a function of the sensor measurement values obtained from the at least one sensor means (210) is lower for sensor measurement values higher than said certain sensor input force value, thereby a falling sensor measurement value obtained from the at least one sensor means (210) indicating an intention by the human hand (10) or finger (1 1, 12, 13, 14, 15) to release a grasp following a gripping movement would result in a faster response in applying a machine output force that is lower than the maximum machine output force applied for the gripping movement. The method according to any of claims 9 and 10, wherein said recalculating step is comprising dynamically recalculating the machine output force applied by at least one of the at least one actuating means (240) as a function of the sensor measurement values obtained from the at least one sensor means (210) by using a predefined algorithm or function so that the continuously recalculated machine output force applied by at least one of the at least one actuating means (240) as a function of the sensor measurement values obtained from the at least one sensor means (210) keeps falling as the sensor measurement values obtained from the at least one sensor means (210) keeps rising above said certain sensor input force value, so that a falling sensor measurement value obtained from the force detecting sensor means (210) indicating an intention by the human hand or finger to release a grasp following a gripping movement would result in an applied machine output force that is lower than the maximum force applied for the gripping movement. The method according to any of claims 9 to 11, wherein said recalculating step is comprising dynamically recalculating, in response to determining that obtained sensor measurement values are above said certain sensor input force value, the machine output force applied by at least one of the at least one actuating means (240) as a function of the sensor measurement values obtained from the at least one sensor means (210) according to a predefined algorithm or function using increasing sensor measurement values continuously obtained from the at least one sensor means (210) during the gripping movement so that the recalculated applied machine output force as a function of increasing sensor measurement values above said certain sensor input force value is substantially constant and corresponds, or substantially to the maximum force applied for the gripping movement, thereby a falling sensor measurement value obtained from the force detecting sensor means (210) indicating an intention by the human hand or finger to release a grasp following the gripping movement would result in an applied machine output force that is lower than the maximum machine output force applied for the gripping movement. The method according to any of claims 9 to 12, wherein said recalculating step is comprising dynamically recalculating, in response to determining that obtained sensor measurement values are above said certain sensor input force value, the machine output force applied by at least one of the at least one actuating means (240) as a function of the sensor measurement values obtained from the at least one sensor means (210) Sdynamic using the following formula for sensor input force values greater than a lowest sensor input force value yielding a maximum output force for the gripping movement: S_dynamic = S_default * (F_sensorAtSaturation - F_sensorthreshold)/(F_sensormax - F_sensorthreshold) , wherein S_dynamic is determining the machine output force as a function of a detected sensor input force above said certain sensor input force value, F_sensorthreshold is the threshold sensor input force value below which no machine output force is applied, F_sensormax is the maximum sensor input force detected for the gripping movement, F_sensorAtSaturation is the currently detected sensor input force value higher than a lowest sensor input force value yielding a maximum machine output force for the gripping movement, and S_default is determining an increased machine output force response as a function of an increasing sensor input force above the threshold sensor input force value and below said lowest sensor input force value yielding a maximum machine output force.