JPH10318862A - Method and apparatus for measurement of action force of structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a method and apparatus in which a force in the Y-axis direction and a force in the Z-axis direction can be separated and measured simply by a method wherein strain gages which are tilted with reference to the X-axis along the X-Y plane to be set inside a structure and which are crossed are arranged, a strain gage which faces the strain gages is arranged and the force in the Y-axis direction and the force in the Z-axis direction are computed by a specific expression. SOLUTION: An F-sensor 31, an S-sensor 32 and an N-sensor 33 which are provided with respective strain gages suitable for measuring a force F in the X-axis direction, a force S in the Y-axis direction and a force N in the Z-axis direction as well as an Fb sensor 34 which is provided with a strain gage suitable for measuring a torque Fb around the Y-axis are arranged in a structure 20. Then, the force F in the X-axis direction, the force S in the Y-axis direction and the force N in the Z-axis direction as well as the torque Fb around the Y-axis are computed by F=Kf (Δa+Δc)-(Δb-Δd), S=Ks (Δa+Δb)+(Δc-Δd)}, N=Kn (Δc+Δd)-(Δa+Δb)} and Fb=Kt (Δa+Δd)-(Δb+Δc)}, where Δa, Δb, Δc, Δd represent respective strain amounts, and Kf , Ks , Kn , Kt represent respective factors.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for measuring the acting force of a structure, and more particularly, to a simple structure constituted by a strain gauge when a plurality of kinds of forces act simultaneously on a wheel supporting member of an automobile or the like. The present invention relates to a technique for separately measuring each acting force using a simple sensor.

[0002]

BACKGROUND OF THE INVENTION For example, various forces act on an axle or an axle support member that supports wheels of an automobile or the like during traveling. This will be described with reference to a simple model shown in FIG. 1.
Acts equivalently on the axle 20 in the vehicle longitudinal direction.
The road surface reaction force (vertical load) N acts on the axle 20 in the vertical direction. At the time of braking, a brake torque Fb for twisting the axle 20 acts.

Japanese Patent Application Laid-Open No. Hei 3-22005 by the applicant of the present application
No. 6 discloses an ideal ABS (Anti-Skid Brake Syst.
A proposal has been made for em) control. In this proposal, a road surface friction coefficient or a physical quantity corresponding thereto is detected in real time, and the brake fluid pressure is controlled so as to produce the maximum braking effect irrespective of the road surface condition. The proposal made by the above publication is to estimate a so-called tire slip ratio and calculate a road surface friction coefficient μ.
Is significantly different from the existing ABS in which the brake fluid pressure is controlled so that the slip rate becomes the maximum slip ratio (vehicle speed-wheel peripheral speed / vehicle speed).

That is, in the existing ABS, the vehicle speed, which should be the basis for calculating the slip ratio, cannot be directly measured. Therefore, the vehicle speed and the slip ratio are obtained by the calculation. Can not do. Also, dry asphalt road surface,
The relationship between the slip ratio and the road surface friction coefficient differs depending on the state of the road surface, such as a wet asphalt road surface, an earth road surface, a frozen road surface, and the like, but the existing ABS cannot cope with this.

In the proposal disclosed in the above-mentioned publication, since the road surface friction coefficient measured in real time or a physical quantity corresponding thereto is used for the ABS control, all the disadvantages of the existing ABS are eliminated.

Although the road friction coefficient μ cannot be directly measured, if the road friction force F and the road normal force N can be measured by the relational expression of μ = F / N, the calculation is performed. Can be determined by:

The applicant of the present application has previously filed Japanese Patent Application No. Hei.
1 (Japanese Unexamined Patent Publication No. 6-241922), a method of embedding a sensor segment composed of a strain gauge at an optimum position in an axle, for example, detecting a frictional force F while reducing the influence of a brake torque Fb acting on the axle. Has been proposed. In this method, a bridge of four sensor segments is configured to be switchable, a horizontal shear force is detected by selecting a first segment configuration, and a brake torque component is determined by a second segment configuration. This is used as a correction term to correct the shearing force detected by the first segment configuration.

However, in the above-described method, a time delay occurs due to the switching of the segment configuration, and a problem remains in calculating the road surface friction coefficient μ in real time. And brake torque F
In addition to the case b, the road surface normal force N or the side force S may act, and these effects cannot be ignored.

On the other hand, by using a sensor segment composed of a strain gauge embedded in an axle or the like, four types of forces, road surface friction force F, road surface normal force N, brake torque Fb, and side force S, are separately measured. Can be effectively used as an input for comprehensive driving optimization control of a vehicle, such as the above-described optimal control of ABS and four-wheel steering control in consideration of side force during cornering. .

[0010]

DISCLOSURE OF THE INVENTION Accordingly, an object of the present invention is to provide a road surface friction force F, a road surface normal force N, a brake torque Fb, and a side force by using a sensor segment comprising a strain gauge disposed on an axle or an axle support member of a vehicle. An object of the present invention is to provide a method and an apparatus for separately measuring S.

Another object of the present invention is to provide a sensor segment comprising a strain gauge, which comprises four types of acting forces of an X-axis direction, a Y-axis direction, a Z-axis direction, and a torque around the Y-axis. The present invention provides a method and an apparatus for easily separating and measuring by using the method.

According to a first aspect of the present invention, there is provided a method for measuring the acting force of a structure, comprising the steps of:
Along the XY plane, the strain gauge a and the strain gauge b, which are inclined with respect to the X axis and intersect with each other, and a second XY plane spaced at a predetermined interval in the Z axis direction with respect to the first XY plane. Along with the strain gauge c facing the strain gauge a and the strain gauge d facing the strain gauge b, an X-axis direction force F, a Y-axis direction force S, a Z-axis direction force N, and Y At least N and S among the torques Fb around the axis are calculated by the following equation. Note that the strain gauge a and the strain gauge b
Are preferably inclined at 45 ° to the X axis and intersect at 90 ° with each other.

[0013]

(Equation 1) Here, Δa, Δb, Δc, and Δd are the amounts of strain measured by the deformation of the strain gauge, and are k _f , k _s , k
_n, k _t each represent coefficients.

In a preferred embodiment, the X axis is a longitudinal axis of the vehicle, the Y axis is a width direction axis of the vehicle, the Z axis is a vertical axis of the vehicle,
The structure is an axle extending substantially in the Y-axis direction or a member that supports the axle. The X-axis direction force F is road surface frictional force, the Y-axis direction force S is side force, and the Z-axis direction force Z is Represents the road surface normal force, and the torque Fb around the Y axis represents the brake torque.

According to a second aspect of the present invention, there is provided an apparatus for measuring a force acting on a structure, comprising:
Along the XY plane, the strain gauge a and the strain gauge b, which are inclined with respect to the X axis and intersect with each other, and a second XY plane spaced at a predetermined interval in the Z axis direction with respect to the first XY plane. Along with the strain gauge c facing the strain gauge a and the strain gauge d facing the strain gauge b, an X-axis direction force F, a Y-axis direction force S, a Z-axis direction force N, and Y It is characterized in that it comprises a calculating means for calculating at least N and S of the torque Fb around the axis by the following equation.

[0016]

(Equation 2) However, Δa, Δb, Δc, Δd is the amount the strain measured by the deformation of the strain gauge, k _f k _s k _n k
_t represents a coefficient.

In a preferred embodiment, the X axis is a longitudinal axis of the vehicle, the Y axis is a width direction axis of the vehicle, the Z axis is a vertical axis of the vehicle,
The structure is an axle extending substantially in the Y-axis direction or a member that supports the axle. The X-axis direction force F is road surface frictional force, the Y-axis direction force S is side force, and the Z-axis direction force Z is Represents the road surface normal force, and the torque Fb around the Y axis represents the brake torque.

The method for measuring the acting force of a structure provided by the third aspect of the present invention includes a method of applying an X-axis direction force F, a Y-axis direction force S, a Z-axis direction force N, and a Y-axis direction force acting on the structure. A method for measuring any two, three, or four of the surrounding torque Fb, wherein the structure has an F sensor having a strain gauge suitable for measuring the X-axis direction force F. An S sensor having a strain gauge suitable for measuring the Y-axis force S, an N sensor having a strain gauge suitable for measuring the Z-directional force N, and measuring the torque Fb around the Y axis. Having a strain gauge suitable for
At least two of the sensors are arranged, and when obtaining the acting force by multiplying the strain amount represented by the output of one of the sensors by a coefficient, a change in the coefficient depending on the magnitude of the other acting force According to the tendency, when another acting force is acting, the acting force is determined using a coefficient determined by the magnitude of the acting force.

According to a fourth aspect of the present invention, there is provided an apparatus for measuring a force acting on a structure, comprising an X-axis force F, a Y-axis force S, a Z-axis force N, and a Y-axis force acting on the structure. An apparatus for measuring any two, three or four of the surrounding torque Fb, wherein the structure has an F sensor having a strain gauge suitable for measuring the X-axis direction force F. An S sensor having a strain gauge suitable for measuring the Y-axis force S, an N sensor having a strain gauge suitable for measuring the Z-directional force N, and measuring the torque Fb around the Y axis. Having a strain gauge suitable for
At least two of the sensors are arranged, calculating means for obtaining the acting force by multiplying a strain amount represented by the output of any one of the sensors by a coefficient, and the coefficient according to the magnitude of the other acting force Storage means for storing a change tendency of the operation force, wherein the operation means reads out, from the storage means, a coefficient corresponding to the magnitude of the force when another action force is acting, and uses the coefficient to determine the effect. It is characterized in that it is configured to seek force.

The technical significance of each aspect of the present invention will be apparent from the following detailed description with reference to the accompanying drawings.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the method and apparatus for measuring the acting force of a structure provided by the first and second aspects of the present invention, as shown in FIG. The four strain gauges a,
b, c, and d are arranged as if they were attached to the front and back surfaces of a plate material 21 having a predetermined thickness made of epoxy resin, metal, silicon, or the like. 2, the arrow X direction indicates the vehicle front-rear direction, the arrow Y direction indicates the vehicle width direction, the arrow Z direction indicates the vertical direction, and the arrow Fb direction indicates the direction around the Y axis. Now
FIG. 1 is a diagram in which an axle 20 related to a left wheel of a vehicle is viewed from a diagonally right rear side. Strain gauges a, b, c, d
Are arranged in search of a position that is not affected as much as possible by an acting force other than the intended acting force. For example, when measuring the X-axis direction force F or the Y-axis direction force S, a position that is hardly affected by the torsional force as noise is selected and arranged, but a simple circle as shown in FIG. In the case of the columnar axle 20, the center surface in the thickness direction of the plate member 21 is arranged horizontally or substantially horizontally along the center line CL of the axle 20. Also, the strain gauges a, b, c, d
It is preferable to make it as small as possible and arrange it at a position close to the center line CL of the axle 20. However, even in the case of a deformed structure such as an axle or a knuckle member that supports the axle, it is possible to find a position where the influence of an acting force other than the acting force related to the measurement purpose is minimized by the finite element analysis.

Each of the strain gauges a, b, c and d is incorporated in a bridge circuit as shown in FIG. 3, and the output of each bridge circuit is input to an arithmetic circuit 9 via an amplifier 8.

1 and 2, when a wheel (not shown) is braked, the road surface frictional force F in the X-axis direction acts in the direction of the arrow in the figure, and this F acts on the axle 20 equivalently.
Z that changes due to vehicle weight and weight movement during braking
An axial normal force N acts in the direction of the arrow in the figure. At the same time, when a brake caliper (not shown) attached to the axle support member clamps the disk to apply braking, a brake torque Fb due to a reaction force applied to the caliper acts on the Y axis, that is, around the axle center line CL. Further, at the time of turning, for example, in the case of a right turn, the side force S in the Y-axis direction acts in the direction of the arrow in the figure.

Now, let us consider a case where the road surface frictional force F acts on the axle 20 to cause shear strain on the axle. In this case, the strain gauges a and c extend, and the strain gauges b and d
Shrinks. Therefore, according to the above equation (1), the output is output in a form in which the deformation of each strain gauge is added, that is, in an amplified form. By multiplying the output strain amount by a predetermined coefficient, the road surface friction force F is detected.

Next, a case is considered in which the side force acts on the axle and the axle is distorted. in this case,
The four strain gauges a, b, c, d contract or expand. Therefore, according to the above equation (2), the output is output in a manner that the deformation of each strain gauge is added, that is, amplified. By multiplying the output distortion amount by a predetermined coefficient, the side force S is detected.

Further, let us consider a case where the normal reaction N acts on the axle and the axle is distorted. In this case, the plate material is bent and deformed in the direction N 'in FIG. In this case, the strain gauges a and b contract, and the strain gauges c and d expand. Therefore, according to the above equation (3), the output is output in a form in which the deformation of each strain gauge is added, that is, in an amplified form. By multiplying the output strain amount by a predetermined coefficient, the normal force N is detected.

Further, consider a case where the brake torque Fb acts on the axle to cause a strain on the axle. In this case, the strain gauges a and d extend, and the strain gauges b and c
Contracts, or the strain gauges a and b shrink, and the strain gauges b and c expand. Therefore, according to the above equation (4), the output is output in a form in which the deformation of each strain gauge is added, that is, in an amplified form. By multiplying the output strain amount by a predetermined coefficient, a normal drag brake torque Fb is output.

It should be noted that the first and second aspects of the present invention are that the X-axis direction force F, the Y-axis direction force S, the Z-axis direction force N, or the torque Fb around the Y-axis are all applied to the strain gauges a and b. , C, d does not mean detection.
If the strain gauges a, b, c, and d having the above configuration are used, the X-axis direction force F, the Y-axis direction force S, and the Z-axis direction are obtained by the above equations (1), (2), (3), and (4). This means that the force Fb around the force N or the Y axis can be measured with high sensitivity.

Next, the third and fourth aspects of the present invention will be described in detail.

The method and apparatus for measuring the acting force of a structure according to the third and fourth aspects of the present invention provide an X-axis direction force F, a Y-axis direction force S, a Z-axis direction force N, Y
A method and apparatus for measuring any two, three, or four of the torques Fb around an axis. As for the force acting around the axle of the vehicle, as shown in FIG. 1, the X-axis direction force is a road surface friction force F, the Y-axis direction force is a side force S, and the Z-axis direction force is a road surface normal force. N, the torque around the Y axis is a brake torque F acting during braking.
b.

Here, an F sensor 3 having a strain gauge suitable for measuring the X-axis direction force F is provided on the structure 20.
1, an S sensor 32 having a strain gauge suitable for measuring the Y-axis direction force S, an N sensor 33 having a strain gauge suitable for measuring the Z-axis direction force N, An Fb sensor 34 having a strain gauge suitable for measuring torque Fb is arranged. Each sensor is
It may be singular or plural. Each sensor may have the strain gauges a, b, c, and d having the structure described in the first and second aspects of the present invention, or may have the strain gauge having another structure. It may be.

For example, when forming the N sensor,
As shown in FIG. 4, a segment formed by attaching strain gauges a and b to the upper and lower surfaces of a square pillar 22 made of resin, metal, silicon, or the like is inserted into a hole formed in the axle 20 as shown in FIG. A configuration in which the axis is oriented in the Y direction can be adopted. Also in this case, it is needless to say that it is arranged in a place where it is hardly affected by the acting force other than the intended acting force (normal force N). In this case, when a normal force N acts, bending deformation indicated by N1 in the figure occurs.
Thus, the normal drag N can be calculated.

[0033]

(Equation 3) Here, a strain amount measured by the deformation of Δa and b strain gauges, k _n is a coefficient.

In this case, as shown in FIG. 5, each of the strain gauges a and b is incorporated in a bridge circuit, and the output of each bridge circuit is passed through an amplifier 8 and then to an arithmetic circuit 9
Is input to

Further, for example, when forming an S sensor, as shown in FIG. 6, a segment in which strain gauges a and b are adhered to the longitudinal side surfaces of a rectangular column made of resin, metal, silicon, or the like is attached to the axle 20. May be arranged in the hole provided in the position shown in FIG. Again,
Needless to say, it is arranged in a place that is hardly affected by an acting force other than the desired acting force (side force S). In this case, when the side force S acts, each of the strain gauges a and b expands or contracts.
, The side force S can be calculated.

[0036]

(Equation 4) Here, Δa and Δb are strain amounts measured by deformation of the strain gauge, and k _S is a coefficient. In addition,
In this case, a circuit configuration similar to that of FIG. 5 can be employed.

FIG. 7 shows a sensor having a configuration obtained by combining the configuration shown in FIG. 4 and the configuration shown in FIG. A pair of strain sensors a and b facing each other in parallel constitute a sensor segment.

FIG. 8 shows an example in which two types of sensor segments whose directions are different from each other by 90 degrees are formed on a plate 21 having a constant thickness.

FIG. 9 shows that a plate 21 having a constant thickness has three X's.
This is an example in which a single-axis direction sensor segment and three single-axis Y-axis sensor segments are formed.

FIG. 10 shows an example in which sensor segments in a predetermined direction are formed on each surface of a cubic base material 23.

FIG. 11 shows an example in which one cross gauge type sensor segment, one X-direction single-axis sensor segment, and one Y-direction single-axis sensor segment are formed on a plate 21 having a constant thickness.

FIG. 12 shows an example in which three cross gauge sensor segments, three X-axis single-axis sensor segments, and three Y-direction single-axis sensor segments are formed on a plate member 21 having a constant thickness.

FIG. 13 shows three cross gauge type sensor segments, three X-direction single-axis sensor segments, and three X-axis sensor segments on the front and back surfaces of a plate 21 slightly thicker than the plate shown in FIG.
This is an example in which three single-axis sensor segments in the Y direction and three single-axis sensor segments are formed on both end surfaces.

FIG. 14 is similar to the configuration shown in FIG. 13, and is an example in which a cross gauge type sensor segment is formed on both end faces instead of forming three single axis sensor segments.

FIGS. 15 and 16 show an example in which a uniaxial sensor segment or a cross gauge type sensor segment in a predetermined direction is formed on each surface of a cubic base material 23. FIG.

FIGS. 17 to 24 show the above-described sensor segments embedded in a structure 20 (axle or the like). Again, the substrate of each sensor segment, whether plate-shaped or cube-shaped, resin,
Metal, silicon, etc. are selected. Also, a sensor segment on the substrate (usually a pair of strain gauges facing each other)
Are located in the structure 20 by searching for a position that is not easily affected by an acting force other than the acting force to be measured by finite element analysis. In this case, when three or more sensor segments of the same type are adjacent to each other as in the example shown in FIG. 12, FIG. 13, or FIG. Also, it is convenient because the one closest to the ideal position can be selected from a plurality of sensor segments and used.

The Fb sensor is constructed by mounting a sensor segment in an axle as a structure 20 as shown in the figure, and by disposing a strain gauge on a caliper support of a knuckle member, for example. be able to. This makes it possible to easily measure the brake torque Fb having a relatively small noise component.

In the method and apparatus for measuring the acting force of a structure according to the third and fourth aspects of the present invention, a coefficient is multiplied by the coefficient of the amount of strain represented by the output of one of the sensors. In determining the acting force, the acting force is determined by using a coefficient determined by the magnitude of the acting force according to the tendency of the coefficient to change according to the magnitude of the acting force.

That is, the F sensor 31 and the S sensor 3
2. Even though the N sensor 33 and the Fb sensor 34 are arranged such that the strain sensor is arranged at a position that is hardly affected by an acting force other than the intended acting force, the N sensor 33 and the Fb sensor 34 are not affected by other acting forces at all. It is difficult to do. The third and fourth aspects of the present invention have been made in view of the above,
On the premise that each sensor is affected by an acting force other than the intended acting force, an attempt is made to obtain an output from which the effects of other acting forces have been removed by a simple method.

The method will be described below.
It is assumed that at least one of the sensor 31, the S sensor 32, the N sensor 33, and the Fb sensor 34 can detect a substantially pure acting force which is not substantially affected by other acting forces. In the following, for the sake of convenience, the description will be given assuming that the N sensor can measure an almost accurate acting force.

Now, when the F sensor 31 is formed on the structure 20, when only the X-axis direction force F is acting on this structure, that is, when the Z-axis direction force N is not acting, for example. Acting force F and strain sensor output ε of F sensor
Relationship with _F is as shown in the characteristic line L ₁ of the graph of FIG. 26, this relationship can also be expressed as Equation (7). However, when a Z-axis direction force N is simultaneously acting on this structure in addition to the X-axis direction force _F , the relationship between the acting force F and the strain amount output ε _F of the F line is shown in the graph of FIG. It becomes like the middle characteristic line L ₂ or L ₃ . Characteristic line L
₂ shows a case example is the Z-axis direction force N of 300kg shows a case acting, the characteristic line L _3, for example the Z-axis direction force N of 600kg acting. These characteristic lines L _{2 and} L ₃ can also be expressed as in equations (8) and (9).

[0052]

(Equation 5)

Each characteristic line L₁, L_Two, L_ThreeThe inclination of the elastic
26 represents the coefficient corresponding to the coefficient, and
In the case of the F sensor in which the Z-axis direction force can be mixed,
Number _FChanges in the Z-axis direction
As the force N increases, the coefficient ξ _FBecomes smaller. And this
And the coefficient of the Z-axis direction force N and F sensor ξ_FRelationship with
Is linear as shown in the graph of FIG.
It can be represented by a linear formula. In equation (10), the coefficient γ
₁Is the slope of the graph in FIG.

[0054]

(Equation 6)

As can be seen from the equations (7), (8) and (9), the equation (10) expresses the sensor output when F is applied to the structure on which the F sensor is disposed, and simultaneously outputs a constant N It can be obtained experimentally by measuring while applying a load and applying at least two types of N loads. In implementing the present invention, the relationship of Expression (10) is stored in a memory 100 such as a ROM.

Therefore, using the F sensor on the premise that the Z-axis direction force component (N load component) is mixed, the N load data separately and accurately measured by the N sensor is expressed by the following formula.
By substituting into (11), the X-axis direction load F from which the N load component has been substantially removed can be measured. In this case, the Z-axis direction force N and the X-axis direction force F can be relatively accurately measured separately.

[0057]

(Equation 7)

In the same manner as described above, for example, when the output of the S sensor is greatly affected by the load F in the X-axis direction, the S load is applied while simultaneously applying a constant F load to the structure on which the S sensor is disposed. By performing an experiment of recording the sensor output in the case where is applied to at least two types of F loads, a relational expression such as Expression (12) can be obtained.

[0059]

(Equation 8)

Therefore, using the S sensor on the premise that the X-axis direction force component (F load component) is mixed, the F load data accurately measured by the F sensor is calculated by the following formula.
By substituting into (13), it is possible to substantially measure the Y-axis direction load S from which the F load component has been removed. In this case, the Z-axis direction force N, the X-axis direction force F, and the Y-axis direction force S can be separated and measured relatively accurately.

[0061]

(Equation 9)

From the above equations (11) and (13), equation (14) can be obtained.

[0063]

(Equation 10)

By the same method as described above, when the output of the remaining Fb sensor is greatly affected by the load S in the Y-axis direction,
By performing an experiment of recording the sensor output when the Fb torque is applied while simultaneously applying a constant S load to the structure on which the Fb sensor is disposed, for at least two types of S loads, the equation (15) is obtained. The following relational expression can be obtained.

[0065]

[Equation 11]

Therefore, using the Fb sensor on the premise that the Y-axis direction force component (S load component) is mixed,
By substituting the F load data accurately measured by the S sensor into equation (16), it is possible to substantially measure the torque Fb around the Y axis from which the S load component has been removed. Here, Z-axis direction force N, X-axis direction force F,
This means that the Y-axis direction force S and the Y-axis torque Fb can be separated and measured relatively accurately.

[0067]

(Equation 12)

From the above equations (14) and (16), equation (17) can be obtained.

[0069]

(Equation 13)

The above processing is performed by a circuit as shown in FIG. That is, each sensor 31, 32, 3
Signals (distortion amounts) from 3 and 34 are input to the arithmetic circuit 9, where the above-described separation processing is performed.

In the above description, assuming that the N load can be accurately measured by a single sensor, the method of separating and measuring each acting force in the order of the F sensor, the S sensor, and the Fb sensor has been described. The order in which the acting forces can be separated and measured depends on the shape of the body and the characteristics of the sensor segments. Also, N, F, S, F
It is not necessary to measure all of b by the above method. If sufficiently accurate acting force can be measured by the arrangement of the sensor segments, it is needless to say that the above method is not necessary.

In the above description, the axle of the vehicle or a member for supporting the axle is taken as an example of the structure. In this case, road surface frictional force F, normal force N, brake torque F
In addition, the side force S can be relatively separately measured in addition to the side force S. Therefore, by measuring these in real time and performing appropriate processing, the ABS force as described at the beginning of this specification can be measured. In addition to being able to provide ideal control, it becomes possible to more appropriately perform comprehensive travel control of the vehicle, such as comfortable travel control during cornering.

Of course, the present invention can be applied as a method and a device for measuring the acting force of various structures in addition to measuring the force acting around the axle of the vehicle as described above. For example, as shown in FIG. 28, the acting force acting on the distal end of the robot arm is measured.
As shown in FIG. 9, it is possible to measure the acting force acting on the tip of the artificial hand. In any case,
According to the invention of the present application, the number of sensor segments composed of strain gauges is reduced, and four composites of the X-axis acting force, the Y-axis acting force, the Z-axis acting force, and the torque Fb around the Y-axis are provided. This makes it possible to separate and measure the effective force relatively easily, and the industrial use value is extremely large.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating a force acting on an axle as an example of a structure to which the present invention is applied.

FIG. 2 is a perspective view showing an example of an arrangement of a strain gauge according to the present invention with respect to the axle.

FIG. 3 is an example of an acting force detection circuit using a strain gauge having the arrangement shown in FIG. 2;

FIG. 4 is a perspective view showing an arrangement example of a strain gauge.

FIG. 5 is an example of an acting force detection circuit using the strain gauges arranged as shown in FIG.

FIG. 6 is a perspective view showing an arrangement example of a strain gauge.

FIG. 7 is a perspective view showing an arrangement example of a strain gauge.

FIG. 8 is a perspective view showing an arrangement example of a strain gauge.

FIG. 9 is a perspective view showing an arrangement example of a strain gauge.

FIG. 10 is a perspective view showing an arrangement example of a strain gauge.

FIG. 11 is a perspective view showing an arrangement example of a strain gauge.

FIG. 12 is a perspective view showing an arrangement example of a strain gauge.

FIG. 13 is a perspective view showing an arrangement example of a strain gauge.

FIG. 14 is a perspective view showing an arrangement example of a strain gauge.

FIG. 15 is a perspective view showing an arrangement example of a strain gauge.

FIG. 16 is a perspective view showing an arrangement example of a strain gauge.

FIG. 17 is a perspective view showing an example of the arrangement of strain gauges in an axle as a structure.

FIG. 18 is a perspective view showing an example of the arrangement of strain gauges in an axle as a structure.

FIG. 19 is a perspective view showing an example of disposing strain gauges in an axle as a structure.

FIG. 20 is a perspective view showing an example of the arrangement of strain gauges in an axle as a structure.

FIG. 21 is a perspective view showing an example of the arrangement of strain gauges in an axle as a structure.

FIG. 22 is a perspective view showing an example of the arrangement of strain gauges in an axle as a structure.

FIG. 23 is a perspective view showing an example of the arrangement of strain gauges in an axle as a structure.

FIG. 24 is a perspective view showing an example of the arrangement of strain gauges in an axle as a structure.

FIG. 25 is a block diagram showing a schematic configuration example of an apparatus for measuring the acting force of a structure according to the present invention.

FIG. 26 is a graph for explaining a specific method of the method for measuring the acting force of a structure according to the present invention.

FIG. 27 is a graph for explaining a specific method of the method for measuring the acting force of a structure according to the present invention.

FIG. 28 is an explanatory diagram showing an application example of the present invention.

FIG. 29 is an explanatory diagram showing an application example of the present invention.

[Explanation of symbols]

 Reference Signs List 8 strain amplifier 9 arithmetic circuit 20 structure (axle) 31 F sensor 32 S sensor 33 N sensor 34 Fb sensor 100 memory

Claims (6)

[Claims] 1. A strain gauge a and a strain gauge b that are inclined with respect to the X axis and intersect with each other along a first XY plane set in a structure, and a first XY
Along with a second XY plane spaced at a predetermined distance in the Z-axis direction from the plane, a strain gauge c facing the strain gauge a and a strain gauge d facing the strain gauge b are arranged in the X-axis direction. Force F, Y-axis force S, Z-axis force N, or
A method for measuring the acting force of a structure, wherein a torque Fb around the Y axis is calculated by the following equation. _{F = k f {(Δa +} Δc) - (Δb + Δd)} S = k s {(Δa + Δb) + (Δc + Δd)} N = k n {(Δc + Δd) - (Δa + Δb)} Fb = k t {(Δa + Δd) - (Δb + Δc )} (where, Δa, Δb, Δc, Δd is the amount the strain measured by the deformation of the strain gauge, k _f, k _s,
k _n, k _t each represent coefficients. ) 2. The X-axis is a longitudinal axis of the vehicle, the Y-axis is a longitudinal axis of the vehicle, the Z-axis is a vertical axis of the vehicle, and the structure is substantially a Y-axis. An axle extending in the direction or a member supporting the axle, wherein the X-axis direction force F is a road surface friction force, the Y-axis direction force S is a side force, the Z-axis direction force Z is a road surface normal force, The method for measuring the acting force of a structure according to claim 1, wherein the torque Fb around the Y axis represents the brake torque. 3. A strain gauge a and a strain gauge b that are inclined with respect to the X axis and intersect with each other along a first XY plane set in the structure, and a first XY
Along with a second XY plane spaced at a predetermined distance in the Z-axis direction from the plane, a strain gauge c facing the strain gauge a and a strain gauge d facing the strain gauge b are arranged in the X-axis direction. Force F, Y-axis force S, Z-axis force N, or
An apparatus for measuring the acting force of a structure, comprising: a calculating means for calculating a torque Fb around the Y axis by the following equation. _{F = k f {(Δa +} Δc) - (Δb + Δd)} S = k s {(Δa + Δb) + (Δc + Δd)} N = k n {(Δc + Δd) - (Δa + Δb)} Fb = k t {(Δa + Δd) - (Δb + Δc )} (where, Δa, Δb, Δc, Δd is the amount the strain measured by the deformation of the strain gauge, k _f k _s k _n
k _t is, each represents a coefficient. ) 4. The X-axis is a longitudinal axis of the vehicle, the Y-axis is a longitudinal axis of the vehicle, the Z-axis is a vertical axis of the vehicle, and the structure is substantially a Y-axis. An axle extending in the direction or a member supporting the axle, wherein the X-axis direction force F is a road surface friction force, the Y-axis direction force S is a side force, the Z-axis direction force Z is a road surface normal force, 4. The apparatus according to claim 3, wherein the torque Fb around the Y axis represents the brake torque. 5. An X-axis direction force F, a Y-axis direction force S, a Z-axis direction force N acting on the structure, and a torque Fb around the Y-axis.
A method for measuring any two, three, or four of the above, wherein the structure has an F sensor having a strain gauge suitable for measuring the X-axis direction force F; An S sensor having a strain gauge suitable for measuring the directional force S, an N sensor having a strain gauge suitable for measuring the Z direction force N, and a strain suitable for measuring the torque Fb around the Y axis At least two of the Fb sensors having a gauge are arranged, and when the acting force is obtained by multiplying the strain amount represented by the output of any one of the sensors by a coefficient, the acting force depends on the magnitude of the other acting force. A method for measuring the acting force of a structure, wherein the acting force is determined using a coefficient determined by the magnitude of another acting force in response to a change tendency of the coefficient. 6. The X-axis direction force F, the Y-axis direction force S, the Z-axis direction force N, and the torque Fb around the Y-axis acting on the structure.
An apparatus for measuring any two, three or four of the above, wherein the structure has an F sensor having a strain gauge suitable for measuring the X-axis direction force F, and the Y-axis. An S sensor having a strain gauge suitable for measuring the directional force S, an N sensor having a strain gauge suitable for measuring the Z direction force N, and a strain suitable for measuring the torque Fb around the Y axis Computing means for arranging at least two of Fb sensors having a gauge, and multiplying a strain amount represented by an output of any one of the sensors by a coefficient to obtain the acting force;
Storage means for storing a change tendency of the coefficient according to the magnitude of another acting force, wherein the calculating means stores a coefficient corresponding to the magnitude of the acting force when the other acting force is acting. , And an apparatus for measuring the acting force by using the coefficient.