WO2002004175A1 - Traitement d'objet - Google Patents

Traitement d'objet Download PDF

Info

Publication number
WO2002004175A1
WO2002004175A1 PCT/GB2001/002865 GB0102865W WO0204175A1 WO 2002004175 A1 WO2002004175 A1 WO 2002004175A1 GB 0102865 W GB0102865 W GB 0102865W WO 0204175 A1 WO0204175 A1 WO 0204175A1
Authority
WO
WIPO (PCT)
Prior art keywords
processing device
instructions
actuator apparatus
processing
control
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/GB2001/002865
Other languages
English (en)
Inventor
Mika Eino Antero Laitinen
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
ROBOTIC TECHNOLOGY SYSTEMS PLC
Original Assignee
ROBOTIC TECHNOLOGY SYSTEMS PLC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by ROBOTIC TECHNOLOGY SYSTEMS PLC filed Critical ROBOTIC TECHNOLOGY SYSTEMS PLC
Priority to AU2001274345A priority Critical patent/AU2001274345A1/en
Publication of WO2002004175A1 publication Critical patent/WO2002004175A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25J—MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
    • B25J9/00—Program-controlled manipulators
    • B25J9/16—Program controls
    • B25J9/1656—Program controls characterised by programming, planning systems for manipulators
    • B25J9/1664—Program controls characterised by programming, planning systems for manipulators characterised by motion, path, trajectory planning

Definitions

  • the present invention relates to processing an object, and in particular, but not exclusively, to generation of control instructions for actuator apparatus used for provision of movable support for a processing device.
  • the workpieces for the goods may be subjected to various processing stages by a processing device, such as a machining tool.
  • the processing may include operations where a tool is brought into a contact with or closely follows a surface or boundary of a workpiece to be processed.
  • Appropriate tools may be used, for example, for machining operations such as milling, tooling, boring, reaming, cutting, deburring, grinding, polishing, finishing and so on.
  • Appropriate processing devices may also be used for operations such as spraying, washing, painting, welding, water jet or laser beam cutting or finishing, brushing and so on.
  • a tool or other processing device is typically attached to a holder assembly.
  • the holder assembly may be moved by actuator apparatus adapted to provide movement of the processing device relative to the workpiece.
  • the holder assembly typically comprises means for providing a firm grip of the tool or other device so that the drive force that is required for the relative movement can be properly transmitted to the processing device and in order to prevent the position of the processing to change relative to the holder.
  • the skilled person is aware of various possible alternatives for the gripping means, and thus they will not be explained in more detail.
  • the actuator apparatus include industrial robots and manipulators and similar apparatus capable of moving the tool holder assembly.
  • the movement may be provided in a three dimensional space (e.g. in x,y,z co-ordinates).
  • the actuators are typically arranged to provide movements along a predefined number of axis i.e. to provide a predefined number of degrees of freedom for a point of the processing device.
  • Conventional machining centres and similar machining apparatus are typically adapted to move along three or four, and in maximum along five axis.
  • Robot-like actuators and similar manipulators may provide movements along six or even more axis i.e. they provide six or more degrees of freedom.
  • the six degrees of freedom are provided by the three axis (xyz) and rotation around each of the axis. The possible axis as well as provision thereof will be explained later in this specification.
  • the operation of the various components of the actuator is controlled based on a predefined set of instructions. More particularly, the movements of the actuator are typically controlled by a controller that follows a processing program.
  • the controller instructs various components of the actuator apparatus such that the actuator apparatus provides a desired movement of the processing device relative to the object.
  • the program may be based, for example, on a prewritten program code and/or on other information obtained e.g. through a machine vision system or from drawings illustrating the object.
  • a machining program may be run such that a machining tool is moved relative to a workpiece by means of the actuator such that a predefined amount of material becomes removed from the surface thereof in order to provide a predefined geometry of the object (shape and dimensions).
  • the machining program may be retrieved from a machining program library, e.g. after recognition of the object by a machine vision system or a request by an operator.
  • a machining program is structured such that it progresses from a location to a next location on the object. These locations will be referred to in the following as points, although no real or visible points may not be provided on the surface of the object. In other words, the tool progresses via subsequent points on the surface of the object based on the instructions in the program.
  • Each of the points is assigned with parameters that are required so that the controller knows how the object should be processed in each of the points.
  • the parameters may define features such as position and orientation of the processing device and direction of the movement thereof.
  • position and orientation of the processing device such as the machining tool
  • TCP tool centre point
  • the tool centre point or any other predefined point in the processing device is provided with the above referenced degrees of freedom. It should be appreciated that in the following a reference to tool centre point (TCP) is- a reference to any appropriate control point that may have been assigned for a processing device.
  • the controller controls the positioning, angular relations and movements of the various components of the robot based on the TCP parameters.
  • the angular relation between the components are often referred to as joint angles. That is, the programmer does not necessarily need to beforehand decide any parameters regarding the position and orientation of said components, but the controller may determine them based on the TCP parameters at each point on the object.
  • the controller applies the TCP parameters at each of the points and automatically interpolates the movement between two points based on approximations that are based on TCP parameters of the previous and the next point on the machining path. Therefore it is not necessary to create beforehand instructions for the positioning and orientation of the various components of the robot or for the various possible parameters for the entire surface area (i.e. at each predefined point) of the object. Instead, it is sufficient if the TCP parameters are defined at said points.
  • At least some of the TCP orientation parameters may be defined as vectors.
  • Euler angles may be used.
  • the orientation data is defined by means of degrees.
  • the Euler angles can be used to define the orientation of a point in a coordinate system, such as in a xyz coordinate system, relative to the axis of the coordinate system.
  • the point can be the TCP or any other control point assigned for the processing device.
  • Control of actuators that employ five axis may require use of a parameter that defines the angle in which the tool should approach the surface of the object, i.e. so called approach vector.
  • Actuators with five degrees of freedom at most can typically be programmed to take this into account by means of conventional programming tools, such as by means of CAD/CAM techniques (computer aided design/computer aided manufacturing).
  • Figure 1 illustrates an example of a six axis actuator, that is an industrial robot 1.
  • the actuator apparatus of Figure 1 is also shown to be provided with a seventh axis A7 by mounting the six axis robot 1 on tracks 10.
  • a robot type actuator apparatus may need to be programmed to perform movements relative to six or more different axis (degrees of freedom).
  • the addition of the sixth degree of freedom may require use of an orientation vector or corresponding parameter in order to be able to define the actual orientation of a predefined control point of the processing device relative to the object.
  • various components of the robot 1 such as arms 4 and 5, a wrist 8, and the body 6 of the robot 1 may perform various movements so as to provide six degrees of freedom for the tool centre point TCP.
  • the wrist 8 of robot 1 on Figure 1 provides said sixth degree of freedom for the movements.
  • the wrist necessitates use of an orientation vector so that the system may control orientation of the tool centre point.
  • the robot or other actuator unit typically forms a closed kinetic system. That is, all axis of a robot belong to a single kinetic chain.
  • the controller of the robot may control this closed kinetic chain based on the processing program and the TCP parameters.
  • various processing applications may require use of one or several so called external axis.
  • the external axis can be provided e.g. by means of rotating table or a conveyor on which the workpiece is attached or by any other device that is a part of a different kinetic system.
  • axis A7 provided by the tracks 10 forms an external axis and provides a seventh degree of freedom for the robot system. It should be appreciated that the number of freedom axis of the entire robot system may be even greater than the shown seven, this being an implementation issue.
  • the further or external axis may not be controlled by the controller of the robot.
  • the controller may provide full or partial control of the external axis
  • the controller may have to perform the control of the two kinetic systems on different basis.
  • the simultaneous control of the internal and external axis may cause also some other problems. It is possible that the separated control of the internal and external axis leads to somewhat different and/or non-synchronised control instructions (i.e. where and how to proceed) or even instructions that are in contradiction to each other in one or several points of the object.
  • the different sets of instructions for internal and external axis may lead to a situation where the positioning and/or orientation of the components of the robot is no longer optimal and/or where the object cannot be reached at all (either the processing device or the object has moved out of the working area). This may be especially the case when complex surfaces and/or boundaries, such as curved or double curved surfaces are to be processed. Therefore a decision may be required how the processing should be proceeded in such situations.
  • the orientation of the tool centre point TCP may be defined by means of orientation vectors or Euler angles in the used coordinate system.
  • Each point on the surface of the object to be processed is assigned with required parameters, e.g. orientation vectors or angles in degrees during the preparation of the machining program.
  • the starting point may be at the rear end A of the boat mould 9.
  • the orientation of the TCP and the various components of the actuator apparatus are set to optimal in the beginning of the processing cycle, the complex surface may lead to a situation where the orientation and/or position thereof are less optimal. The problem may be worsened if the processing includes use of an additional kinetic system.
  • the arms and the wrist can be kept as "straight" as possible. It may also be advantageous to keep the position of the wrist as constant as possible during the processing cycle. By means of this it is possible to avoid unnecessarily rapid accelerations and/or decelerations during the machining process, especially between the various axis of the robot itself. Such rapid changes may influence the process and affect negatively the final result of e.g. a machining or painting process.
  • the optimisation of the orientation of the arm and the wrist does not usually cause any major difficulties as long as the surface to be processed does not change in direction.
  • the processing may be applied e.g. to a surface with double- curvature and/or a curved surface that narrows towards one end thereof.
  • An example of this type of surfaces is the front end of the boat 9 of Figure 1.
  • parallel tool movement paths will cross or join in a common point.
  • a situation may occur that is referred to as 'working area overrun'.
  • the processing devices usually have a desired orientation in which it should be applied to the object.
  • the controller tries to apply a rotating tool in a substantially normal orientation to the surface of the object throughout the surface of the object (that is, the approach vector of the tool centre point is tried to be kept substantially normal to the surface of the object).
  • problems may lead to problems that relate to the orientation of the wrist and/or arms of the robot. Problems may be expected especially if two kinetic systems are involved in the processing. Difficulties may be also expected when automated or semi-automated programming techniques are used.
  • Spherical surfaces are believed to be the most problematic.
  • a human arm advances from a first point in the equator in the north-to-south direction or east-to- west direction to a second point in the opposite side of the globe. If one tries to keep at least one finger either in the direction of the longitude or the latitude, he will notice that the position of his arm in the second point will be different depending whether the globe was circulated along the equator or over the north pole.
  • the embodiments of the present invention aim to address one or several of the above problems.
  • a method of generating instructions for actuator apparatus comprising: generating control parameters based on data of the object, said control parameters associating with the orientation of the processing device during the processing of the object and being generated for a plurality of locations on the object so that each of the locations is assigned with at least one control parameter; selecting a reference point; determining a desired orientation of the processing device at the reference point; determining at least one reference parameter that associates with the desired orientation of the processing device at the reference point; and based on said at least one reference parameter, modifying those of the control parameters that associate with locations on the object within a predefined area.
  • the at least one parameter is changed in all locations within a predefined distance from the reference point.
  • the at least one parameter may also be changed linearly throughout a path of movement of the processing device relative to the surface of the object between the reference point and a point substantially on the edge of the predefined area.
  • the processing device may be provided with at least six degrees of freedom for the movement thereof.
  • the method may comprise further steps of determining during the generation of the control instructions that an undesired orientation of the processing device will occur in a location on the object; selecting said location to form a reference point; and modifying the control parameters within a distance from said selected reference point.
  • At least one of the control parameters assigned for a location on the object may associate with an axis that is external for the kinetic system of the actuator apparatus.
  • the external axis may be provided by means of moving the object relative to the actuator apparatus or moving the entire actuator apparatus relative to the object.
  • More than one reference point may be selected.
  • a method of processing an object by means of a processing device attached to actuator apparatus comprising: generating data regarding the contour of the object to be processed; generating control parameters based on said data for controlling orientation of the processing device when processing the object, the control parameters associating with a plurality of locations on the object so that each location is assigned with at least one control parameter; selecting a reference point that associates with the object; determining at least one reference parameter that associates with a desired orientation of the processing device at the reference point; and based on said at least one reference parameter, modifying said control parameters at locations that are within a predefined area; and processing the object based on the modified control parameters.
  • a method of generating instructions for actuator apparatus for processing an object by means of a processing device attached to the actuator apparatus, said actuator apparatus providing the processing device with a first number of degrees of freedom in a three dimensional space comprising the steps of: defining information of the contour of the object to be processed; generating a first set of instructions by means of an instruction generation tool based on said information of the contour, said first set of instructions being for controlling movements of an actuator capable of providing the processing device with a second number of degrees of freedom, said second number being less than said first number; determining additional information that associates with at least one further degree of freedom; and generating a second set of instructions based on said first set of instructions and the additional information for use in the control of the operation of the actuator apparatus for processing the object with the processing device provided with the first number of degrees of freedom.
  • the first set of instructions may be generated by means of a computer aided design and manufacture programming technique and provides the processing device with five degrees of freedom.
  • the actuator apparatus may comprise an industrial robot enabled to provide at least six degrees of freedom for the processing device.
  • an apparatus for generation of instructions for actuator apparatus adapted for processing an object by means of a processing device attached to the actuator apparatus based on said instructions, comprising: a data input for input of data defining the shape of the object; processor means for generating control parameters based on the input data for the control of the orientation of the processing device during the processing of the object, the processor means being adapted to generate said control parameters for a plurality of locations on the object so that each of the locations becomes assigned with at least one control parameter, processor means for determining a desired orientation of the processing device at a reference point that associates with the object; processor means for determining at least one reference parameter that associates with the desired orientation of the processing device at the reference point; and processor means for modifying, based on said at least one reference parameter, control parameters that associate with locations on the object within a predefined area.
  • a system for processing objects comprising: actuator apparatus adapted to move a processing device attached to the actuator apparatus relative to an object to be processed; a controller for controlling the operation of the actuator apparatus; and an apparatus for generating instructions for the controller, said instructions defining control parameters for the control of the orientation of the processing device during the processing of the object for a plurality of locations on the object so that each of the locations becomes assigned with at least one control parameter, wherein the apparatus for generating the instruction is adapted to modify the control parameters that associate with locations on the object within a predefined area based on information of at least one parameter that associates with a desired orientation of the processing device at a selected reference point.
  • an arrangement for generating instructions for actuator apparatus for processing an object by means of a processing device attached to the actuator apparatus, said actuator apparatus providing the processing device with a first number of degrees of freedom in a three dimensional space comprising: means for defining information of the contour of the object to be processed; processor means for generating a first set of instructions by means of an instruction generation tool based on said information of the contour, said first set of instructions being for controlling movements of an actuator capable of providing the processing device with a second number of degrees of freedom, said second number being less than said first number; processor means for determining additional information that associates with at least one further degree of freedom; and processor means for generating a second set of instructions based on said first set of instructions and the additional information for use in the control of the operation of the actuator apparatus for processing the object with the processing device provided with the first number of degrees of freedom.
  • the embodiments of the invention may enable provision of instructions for actuators (such as control programs) such that rapid changes in the orientation of the components of the actuator apparatus and/or non-optimal orientation said components may be avoided.
  • the embodiments may enable smoother movements of a processing device relative to the object to be processed, thus enabling better quality of the processed surfaces.
  • the embodiments may also enable a pre-check of the instructions in order to verify that the processing device may reach all parts of the object to be processed and/or that none of the components will overrun its working area during the actual processing of the object.
  • the instruction correcting procedure may be automatic.
  • Figure 1 shows a system that may employ an embodiment of the present invention
  • Figure 2 shows a schematic presentation of the paths of movement in an embodiment of the present invention
  • Figure 3 illustrates an orientation of a processing device resulting from use of a conventional technique for generation of a machining program for the Figure 1 object;
  • Figure 4 illustrates the orientation of the processing device holder obtainable by means of the principles of the present invention
  • FIGS. 5a to 5c illustrate the processing device orientation in various locations on relative to the object
  • Figure 6 is a flowchart illustrating the operation of one embodiment of the present invention.
  • Figures 7a and 7b illustrate a further embodiment of the invention
  • Figure 8 shows an instruction generation apparatus
  • Figure 9 is a flowchart illustrating the operation of a further embodiment of the present invention.
  • Figure 1 shows a machining system employing an industrial robot 1 mounted on tracks 10 for actuating a tool holder assembly 3.
  • the basic structure and operation of a six axis industrial robot is known by the skilled person, and will thus not be explained in detail. It is sufficient to note that a robot typically comprises a frame portion and one or several swivelling and/or rotational arms so that it is capable of providing different movements of the tool in the working area thereof.
  • the frame portion 6 can be rotated as indicated by double-headed arrow A1.
  • a first arm 5 is pivotally attached to the frame portion 6, and can be pivoted as indicated by double-headed arrow A2.
  • a second or outer arm 4 is pivotally attached to the first arm 5.
  • the pivoting between the first and second arms is actuated by the bar 15, and occurs as indicated by arrow A3.
  • a pivoting point 7 is arranged at the end of the outer arm 4 to enable movement as indicated by double- headed arrow A4.
  • a short mounting arm or fixture 8 projects from the pivoting point 7 and provides an attachment point for the tool holder assembly 3.
  • the mounting arm of a robot is typically referred to as a wrist.
  • the mounting arm 8 may revolve around an axis that is illustrated by the two-headed arrow A5. In a typical construction the frame and arm components provides axis 1 to 5.
  • a rotating tool 11 is mounted on the tool holder 3.
  • the tool 11 is adapted revolve around axis A6.
  • the rotational and/or swivelling movements of the various components of the robot may be provided by suitable actuators, such as by servomotors and/or pneumatic or hydraulic cylinders.
  • a tool centre point TCP is shown to be located at the outer end of the tool 11 on the rotational axis thereof.
  • the actuator apparatus may be adapted to provide other number of possible axis than what is illustrated by Figure 1.
  • axis A7 i.e. the tracks 10
  • the robot may be provided with an additional pivoting point, thereby enabling a greater number of degrees of freedom for the processing apparatus.
  • the operation of the various components of the robot 1 is controlled by a controller unit 2.
  • the control unit 2 is arranged to follow a set of instructions i.e. to process a reprogrammed processing program that has been prepared for an object 9 so that the object may be processed by means of the robot 1 in a desired manner.
  • the program may have been prepared by means of an appropriate programming tool, such as by a CAD/CAM tool modified in accordance with the embodiments of the invention.
  • a part of the information on which the processing may be based on may be fetched/received from an internal or external database or from an imaging apparatus of a machine vision system (not shown in Figure 1) via an appropriate communication media.
  • the controller 2 typically includes required data processing and storage capability, such as an appropriate central processing unit (CPU) and necessary software for running the control applications in the processing unit.
  • the central processing unit may be based on microprocessor technology.
  • the controller unit may be based on a PentiumTM processor, even thoug a less or more powerful! processor may also be employed depending on the requirements of the system and the objects to be handled.
  • the controller 2 may be provided with appropriate memory devices, drives, display means, a keyboard, a mouse or other pointing device and any adapters and interfaces that may be required.
  • an appropriate imaging software is typically required.
  • the controller may also be provided with a network card for installations where the machining system is connected to a data network, such as to a network that is based on use of Internet Protocol (IP) for data transporation.
  • IP Internet Protocol
  • a data communication connection 12 is provided between the controller 2 and the robot 1 for transmission of data between the robot and the controller.
  • the exemplifying workpiece 9 of Figure 1 comprises a hull frame for a boat. As is well known, the hull of a boat may have a curved surface, and especially the front end thereof may be of double curved contour.
  • the workpiece 9 may be supported by any appropriate supporting means, such as by an appropriate fixed support or by a support apparatus providing movement thereof, such as a rotating table or a conveyor.
  • the tool 11 is used for providing the desired shape of the boat. Some applications may require use of several different tools during the processing, e.g. one for the rough machining, one for the machining and one for the finishing stages.
  • the tool holder assembly 3 may comprise a spindle for rotating the tool 11.
  • the skilled person is familiar with the operation and structure of the various spindle arrangements, and thus the internal parts within the spindle housing are not shown or explained in more detail. It is sufficient to note that if a rotating tool is to be used, a suitable spindle apparatus may be used to provide the drive force for the rotating tool 11.
  • the spindle may be driven by an appropriate motor. The most commonly used alternatives for the motor are at the present electric, pneumatic and hydraulic motors, although other possibilities are not excluded.
  • the rotation of the tool around the rotational axis thereof may be provided in two directions.
  • the rotating tool 11 may be attached to the spindle by means of a chuck, a mandrel or other appropriate clamping device (not shown).
  • the rotating machining tool 11 is arranged to rotate around a so called tool centre line TCL.
  • TCL tool centre point
  • the controller 2 is instructed to control the operation of the various components of the robot 1 based on the orientation and location of the control point of the processing device, i.e. the TC of the tool H .
  • Figure 2 shows schematically a top view of the subsequent paths of movement 20 of the tip of the tool 11 on the surface of the other half of the boat 9 of Figure 1.
  • the boat surface is machined by moving the tool in subsequent movements 20 in the direction form the rear of the boat to the front of the boats, i.e., in direction from point A to point B.
  • the subsequent paths join at the tip of the boat, i.e. at point B.
  • Each of the paths 20 consists of a plurality of successive points 21 (for clarity reasons, only a part of the points is shown).
  • the orientation of the tool centre point is defined in the used coordinate system at each of these points.
  • the computation is accomplished by an appropriate programming tool (for a possible tool, see Figure 8).
  • the controller will then control the operation of the actuator apparatus based on this program.
  • Figure 3 illustrates a situation that may occur with curved surfaces.
  • the arm 4 of the robot 1 may become driven outside (i.e. "overrun") the working area.
  • the controller has turned the wrist 8 of the robot into an extremely angled (and thus undesired) position shown in Figure 3.
  • Figure 4 illustrates the orientation of the wrist close to the point B when the wrist 8 has a "correct” or an optimal orientation.
  • the procedure for obtaining the desired i.e. optimal orientation of the tool holder 3 and the wrist 8 will now be described in more detail with reference to Figures 4 to 8 and the flowchart of Figure 6.
  • the definition orientation of the processing device refers to the orientation of the tool holder (and thus the tool) or similar processing device and/or also to the orientation of the wrist or similar apparatus supporting the processing device, where appropriate and not especially excluded.
  • the contour of the surface of the object 9 may need to be defined so that it is possible to generate a set of instructions for the actuator apparatus 1 so that the surface of the object may be processed by the tool 11.
  • the initial surface of a workpiece for an object may be different in dimensions and/or contour than the finished i.e. final surface of the object.
  • the term "surface” refers in this specification to the finished surface of the object if nothing else is indicated.
  • the information may be obtained e.g. based on the drawings for the object or other information prepared for the manufacture of the object, by means of a machine vision system or other system capable of producing the required object information and so on.
  • the required parameters for the internal and possible external axis may be computed by means of a conventional programming procedure, such as by means of a CAD/CAM programming tool. That is, during the programming work, required orientation vectors and other necessary parameters at different locations i.e. points within a defined working area may be initially computed at each of the points 21 between the first and last points A, B in each of the paths 20 in any appropriate manner.
  • the point B at the front end of the boat frame 9 is selected to form a reference point (RP).
  • RP reference point
  • the reference point does not necessarily need to be located at the end point of the machining path or in the common point of two or more machining paths.
  • An optimal orientation of the TCP is defined for the reference point.
  • optimal external axis parameters may be defined in the reference point.
  • the parameters defined for the reference point RP may then be used to change one or several of the parameters used at the other points. That is, the user, e.g. the person installing the program into the controller may tell or teach to the controller good orientation parameters at the reference point RP.
  • the orientation parameters are then modified at the other points based on the information of the desired orientation at the reference point RP.
  • the correction of the parameters may also be accomplished during the generation of the program, that is before the program is input in the controller.
  • the correction is preferably made within a defined (limited) distance or range from the reference point RP.
  • the dashed line 16 indicated the area within which the control parameters are to be corrected based on the reference point RP.
  • a possibility is to limit the correction area such that the correction applies throughout the front end area of the boat frame 9.
  • the machining paths 20 converge at the front end area i.e. the front end forms an area where the frame 9 has a double curved contour and where a correction of the orientation parameters may be required.
  • the size of the area 16 may be defined beforehand or it may be defined individually for each reference point based on other information of the object.
  • the area sizing may be a dynamic process.
  • the program generation tool monitors for any overrun situations that could occur if no correction is provided. Whenever a possible overrun is detected at a location on the object, this location is selected to form a reference point. The position of the processing device is corrected, and the corrected parameters are used as a base for correction within a range from the selected reference point.
  • the programming tool may be adapted to accomplish this automatically.
  • the range may be defined based on information of the object, and may vary between different reference points on the object.
  • the modification of the orientation vectors is accomplished preferably such that the change is linear between the starting point of the correction (i.e. at the edge of the defined area) and the reference point RP.
  • This provides a smooth correction of the vectors between the two points.
  • the position of the wrist 8 remains substantially constant relative to the arm 4 in various locations relative to the object. Since the orientation information is corrected in all such points that are close to the reference point B and that may require correction, a proper orientation of the wrist may be provided such that the position of the wrist is not changed too rapidly in zones with complicated surfaces and/or changing contours. It may also be possible to more effectively avoid overrun situations since the use of the reference point may enable a localised control of the various components of the robot so that any overrun is prevented.
  • At least one additional reference point is selected.
  • the additional reference point may be used e.g. when there is a discontinuity in the contour of the surface to be processed.
  • Figures 7A and 10B illustrate a curved surface with a recess 25 on the top portion thereof.
  • Three reference points RP1, RP2 and RP3 are assigned for the object 9.
  • the point RP1 is for the overall correction of the machining parameters whereas the points RP2 and RP3 are applied only for the area of the recess 25, and more particularly, at the respective ends of the recess 25.
  • Each of the reference points may be used as a base for a local correction in the vicinity of the reference points.
  • the correction may be applied based on a single reference point, that is such that only one reference point is taken into account.
  • two or more reference points (such as RP2 and RP3 or RP1 to RP3) are taken into account when correcting the TCP orientation parameters and/or the external axis parameters.
  • the workpiece may be supported by another actuator device or by a conveyor arrangement so that the workpiece 9 may be moved in a controlled manner relative to the tool 11. Therefore it should be understood that while in the exemplifying embodiments the tool 11 is moved relative to the object 9, the relative movement between the tool and the object may also be provided by moving the object or by moving both the object and the tool.
  • the provision of the external axis may increase the importance of the correction of the control parameters, especially those parameters that associate with the external axis.
  • FIG. 8 shows a schematic presentation of an apparatus for the generation of the instructions.
  • the apparatus 30 is shown to comprise an input 32 for data that associates with the object. The may define the shape and/or size and/or further characteristics of the object so that it is possible to generate processing instructions for the object.
  • a processor 31 is adapted to generate the control parameters based on the input data, to determine a desired orientation of the processing device at a reference point, to determine at least one reference parameter that associates with the desired orientation of the processing device, and to modify the control parameters.
  • the apparatus 30 may comprise a processor entity for accomplishing all the required data processing or that the processor functions may be distributed for several processor units. This is an implementation issue.
  • the apparatus 30 is shown to interface the controller 2 of a robot via a data communication connection 36.
  • the apparatus 30 may also include a database 33 for storing any information that may be required for the program generation. Additional input means, such as a keyboard 34 and a display 35 may also be provided.
  • a CAD/CAM system or similar per se conventional arrangement may be employed for the generation of a first set of instructions, said first set of instructions being for controlling movements of an actuator that is capable of providing the processing device with a number of degrees of freedom that is less than what is actually required by a robot or similar device providing at least six degrees of freedom for a processing device.
  • the first set of instruction may be suitable for controlling a five axis machine tool.
  • the input for the process of generation of the first set of instructions comprises information of the contour of the object to be processed.
  • additional information is determined, said additional information being associated with at least one further degree of freedom.
  • the additional information preferably comprises information of the orientation of the processing device.
  • a second set of instructions is then generated based on said first set of instructions and the additional information.
  • the second set of instructions is adapted to be suitable for controlling operation of the robot.
  • the additional information may also comprise information that associates with an axis that is external to the kinetic system of the robot.
  • the orientation information of the second set of information may be modified as described above with reference to Figures 1 to 7.
  • the method may be implemented by means of an apparatus similar to the data processing apparatus 30 of Figure 8.

Landscapes

  • Engineering & Computer Science (AREA)
  • Robotics (AREA)
  • Mechanical Engineering (AREA)
  • Manipulator (AREA)
  • Numerical Control (AREA)

Abstract

La présente invention concerne la génération d'instructions destinées à un appareil (1) positionneur adapté pour traiter un objet (9) à l'aide d'un dispositif (3) de traitement fixé à cet appareil à partir de ces instructions. Selon ce procédé, des paramètres de commande sont générés à partir de données de cet objet, ces paramètres de commande étant associés à l'orientation du dispositif (3) de traitement pendant le traitement de cet objet (9), et ces paramètres sont générés pour une pluralité de localisations sur cet objet de sorte qu'au moins un paramètre de commande soit affecté à chacune de ces localisations. On sélectionne un point de référence (RP). On détermine une orientation souhaitée de ce dispositif (3) de traitement au niveau de ce point de référence et on détermine au moins un paramètre de référence qui s'associe avec l'orientation souhaitée du dispositif de traitement au niveau de ce point de référence. Ces paramètres de commande qui s'associent à des localisations sur cet objet (9) dans une zone (16) prédéfinie sont ensuite modifiés à partir d'informations de ce ou ces paramètres de référence.
PCT/GB2001/002865 2000-07-07 2001-06-27 Traitement d'objet Ceased WO2002004175A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU2001274345A AU2001274345A1 (en) 2000-07-07 2001-06-27 Processing an object

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB0016828.6 2000-07-07
GB0016828A GB2364575B (en) 2000-07-07 2000-07-07 Processing an object

Publications (1)

Publication Number Publication Date
WO2002004175A1 true WO2002004175A1 (fr) 2002-01-17

Family

ID=9895299

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB2001/002865 Ceased WO2002004175A1 (fr) 2000-07-07 2001-06-27 Traitement d'objet

Country Status (3)

Country Link
AU (1) AU2001274345A1 (fr)
GB (1) GB2364575B (fr)
WO (1) WO2002004175A1 (fr)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1576689A4 (fr) * 2002-11-19 2009-12-09 Ultrastrip Systems Inc Appareil robotique pour enlever un revetement sous forme de couche de peinture/couche de protection
EP2345512A1 (fr) 2010-01-14 2011-07-20 Syddansk Universitet Procédé pour trouver des trajectoires conjointes possibles pour robot N-DOF avec un procédé invariant de rotation (N>5)
US8972056B2 (en) 2010-01-14 2015-03-03 Syddansk Universitet Method of finding feasible joint trajectories for an n-dof robot with rotation invariant process (n>5)
DE102018201716A1 (de) * 2018-02-05 2019-08-08 Robert Bosch Gmbh Schleifmitteleinheit
CN113459112A (zh) * 2021-09-03 2021-10-01 成都卡诺普机器人技术股份有限公司 一种机器人与外部轴协同的方法及装置

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5241249A (en) * 1991-01-09 1993-08-31 Commissariat A L'energie Atomique Process for controlling a robot arm by defining substitution paths
EP0577437A1 (fr) * 1992-07-03 1994-01-05 Daihen Corporation Dispositif de commande pour un robot industriel

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6198407A (ja) * 1984-10-19 1986-05-16 Fanuc Ltd ロボツト制御軸の位置デ−タ生成方法
GB9021879D0 (en) * 1990-10-09 1990-11-21 Steel Castings Res Apparatus and method for making a shaped article
US5429682A (en) * 1993-08-19 1995-07-04 Advanced Robotics Technologies Automated three-dimensional precision coatings application apparatus
US5511147A (en) * 1994-01-12 1996-04-23 Uti Corporation Graphical interface for robot
GB9403644D0 (en) * 1994-02-25 1994-04-13 Advanced Robotics Res Manipulator controller

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5241249A (en) * 1991-01-09 1993-08-31 Commissariat A L'energie Atomique Process for controlling a robot arm by defining substitution paths
EP0577437A1 (fr) * 1992-07-03 1994-01-05 Daihen Corporation Dispositif de commande pour un robot industriel

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
"OPTIMAL MANIPULATOR POSITION AND ORIENTATION DETERMINATION SCHEME SUBJECT TO JOINT CONSTRAINTS", IBM TECHNICAL DISCLOSURE BULLETIN, IBM CORP. NEW YORK, US, vol. 31, no. 6, 1 November 1988 (1988-11-01), pages 217 - 218, XP000023774, ISSN: 0018-8689 *
SHIBATA T ET AL: "MOTION PLANNING BY GENETIC ALGORITHM FOR A REDUNDANT MANIPULATOR USING AN EVALUATION FUNCTION BASED ON CRITERIA OF SKILLED OPERATORS", PROCEEDINGS OF THE 1995 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION. NAGOYA,JAPAN, MAY 21 - 27. 1995, PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION, NEW YORK, IEEE, US, vol. 3, 21 May 1995 (1995-05-21), pages 2476 - 2481, XP000731606, ISBN: 0-7803-1966-4 *
YONG K HWANG ET AL: "A GLOBAL MOTION PLANNER FOR CURVE-TRACING ROBOTS", PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION SAN DIEGO, MAY 8 - 13, 1994, LOS ALAMITOS, IEEE COMP. SOC. PRESS, US, vol. 1 CONF. 11, 8 May 1994 (1994-05-08), pages 662 - 667, XP000478926, ISBN: 0-8186-5332-9 *

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1576689A4 (fr) * 2002-11-19 2009-12-09 Ultrastrip Systems Inc Appareil robotique pour enlever un revetement sous forme de couche de peinture/couche de protection
EP2345512A1 (fr) 2010-01-14 2011-07-20 Syddansk Universitet Procédé pour trouver des trajectoires conjointes possibles pour robot N-DOF avec un procédé invariant de rotation (N>5)
WO2011086032A1 (fr) 2010-01-14 2011-07-21 Syddansk Universitet Procédé pour trouver des trajectoires d'articulations réalisables pour un robot à n degrés de liberté avec traitement d'invariants de rotation (n > 5)
US8972056B2 (en) 2010-01-14 2015-03-03 Syddansk Universitet Method of finding feasible joint trajectories for an n-dof robot with rotation invariant process (n>5)
DE102018201716A1 (de) * 2018-02-05 2019-08-08 Robert Bosch Gmbh Schleifmitteleinheit
CN113459112A (zh) * 2021-09-03 2021-10-01 成都卡诺普机器人技术股份有限公司 一种机器人与外部轴协同的方法及装置
CN113459112B (zh) * 2021-09-03 2021-12-17 成都卡诺普机器人技术股份有限公司 一种机器人与外部轴协同的方法及装置

Also Published As

Publication number Publication date
AU2001274345A1 (en) 2002-01-21
GB2364575A (en) 2002-01-30
GB0016828D0 (en) 2000-08-30
GB2364575B (en) 2004-10-27

Similar Documents

Publication Publication Date Title
Shembekar et al. Trajectory planning for conformal 3d printing using non-planar layers
US6274839B1 (en) Method and apparatus for building up a workpiece by deposit welding
Xu et al. Novel hybrid robot and its processes for precision polishing of freeform surfaces
DK2285537T3 (en) Device and method for computer-assisted generation of a manipulatorbane
US8972056B2 (en) Method of finding feasible joint trajectories for an n-dof robot with rotation invariant process (n>5)
Feng-yun et al. Development of a robot system for complex surfaces polishing based on CL data
Sun et al. An on-line tool path smoothing algorithm for 6R robot manipulator with geometric and dynamic constraints
CN108274472B (zh) 一种工业机器人加工工艺自适应的空间运动方法
EP2523786B1 (fr) Procédé pour trouver des trajectoires conjointes possibles pour robot N-DOF avec un procédé invariant de rotation (N>5)
JP6390832B2 (ja) 加工軌道生成装置と方法
CN110586960B (zh) 用于加工工件的方法、数控装置以及机床
Asakawa et al. Automation of chamfering by an industrial robot; for the case of hole on a free curved surface
GB2248571A (en) Computer controlled work treating robot
Xu et al. Heuristic kinematics of a redundant robot-positioner system for additive manufacturing
Murphy et al. CAD directed robotic deburring
WO2002004175A1 (fr) Traitement d'objet
JP4531297B2 (ja) ６軸制御ｎｃプログラム生成方法及び生成装置、並びに６軸制御ｎｃプログラム生成プログラム及びこのプログラムを記憶したコンピュータ読み取り可能な記録媒体
JP2003044109A (ja) ワ−ク座標系設定手段を持つ多軸工作機械の数値制御装置
GB2363861A (en) Processing an object, eg a workpiece, by a tool
JPH11198073A (ja) 産業用ロボットの姿勢生成方法
Bo et al. Review of robotic control strategies for industrial finishing operations
JP2003311666A (ja) ロボットの教示方法および教示装置
KR102776991B1 (ko) 다관절 로봇의 중쇠관절의 연속 제어방법, 그 다관절 로봇 및 그 연속제어 소프트웨어
KR100386676B1 (ko) 테이블 회전/기울임 방식의 5축가공용 엔씨데이터생성방법 및 그것을 내장한 기록매체
Nemer et al. Off-line nominal path generation of 6-DoF robotic manipulator for edge finishing and inspection processes

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NO NZ PL PT RO RU SD SE SG SI SK SL TJ TM TR TT TZ UA UG US UZ VN YU ZA ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE TR BF BJ CF CG CI CM GA GN GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: JP