Impedance control device

Abstract

To improve the safety of a movable body used while moving an outdoor or indoor travel path including a non-flat region with unevenness and slopes by suppressing an influence of gravitational acceleration change.SOLUTION: The present invention relates to an impedance control device 1 that controls a movable body with an operation part, and includes: a storage part 221 which stores information including information related to an operation part, controlled under force control, of the operation part; a sensor 500 which detects a gravitational acceleration direction; a detection part 211 which detects an inclination of the center of gravity to the detected gravitational acceleration direction; and a control part 213 which executes impedance control related to the operation of the operation part based upon the information including the information related to the operation part and information including information related to the inclination of the center of gravity of the movable body to the gravitational direction.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an impedance control device. [Background technology]

[0002] In recent years, technologies for controlling the dynamic behavior of moving objects, manipulators, etc. have become widespread. In particular, among force control techniques, techniques using impedance control are becoming more widespread.

[0003] Impedance control is expected to contribute to improving work safety in environments where people work collaboratively, because it can perform smooth force control based on inertia, viscosity, and rigidity, taking external forces into account.

[0004] With regard to impedance control, for example, in a robot control device that can easily detect collisions, a drive control unit, which is a component of the robot control device, identifies the action force fS actually acting on the force sensor in the robot coordinate system based on the position S of the tool center point and the detection value of the force sensor. In this process, the drive control unit substitutes the target force fSt and the action force fS into the equation of motion for impedance control to obtain a force-derived correction amount ΔS, which is used to remove the gravitational acceleration component from the action force fS and perform gravitational acceleration compensation for the action force fS (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-19057 Summary of the Invention [Problem to be solved by the invention]

[0006] As with the technology described in Patent Document 1, gravitational acceleration compensation is a force compensation method that is commonly used when performing force control, and it is possible to perform force control that theoretically eliminates the influence of gravitational acceleration. On the other hand, this gravitational acceleration compensation requires that the direction of gravitational acceleration be clearly or approximately guaranteed.

[0007] Conventional power equipment is primarily designed to be installed indoors or used indoors, so the direction of gravitational acceleration does not change from the time of installation, and this does not pose a problem. However, in a robot or the like that is used while moving outdoors, the direction of gravitational acceleration changes due to the influence of unevenness or slopes on the ground.

[0008] Furthermore, when rigid control against disturbances is performed by increasing servo stiffness based on position control, as in conventional industrial robots, the effect of changes in gravitational acceleration is relatively minor and does not pose a major problem. However, in the case of mechanical impedance control, which is a soft control aimed at collaborative work with humans, the effects of changes in gravitational acceleration cannot be ignored, and in order to deal with this, rigid control is required by increasing the mechanical impedance, which poses a challenge in making it difficult to improve safety.

[0009] Therefore, the present invention has been made in consideration of the above-mentioned problems, and aims to provide an impedance control device that suppresses the effects of changes in gravitational acceleration and improves safety for movable objects used while moving on outdoor or indoor running paths that include uneven areas with bumps and slopes. [Means for solving the problem]

[0010] Form 1: One or more embodiments of the present invention propose an impedance control device that controls a movable body having an operating unit, and includes: a memory unit that stores information including information about the operating unit that is controlled by force control among the operating units; a sensor that detects the direction of gravitational acceleration; a detection unit that detects the inclination of the center of gravity of the movable body relative to the detected gravitational acceleration direction; and a control unit that performs impedance control regarding the operation of the operating unit based on information including information about the operating unit and information including information about the inclination of the center of gravity of the movable body relative to the gravitational acceleration direction.

[0011] Form 2: In one or more embodiments of the present invention, the control unit includes a compensation value setting unit that sets a compensation value in impedance control related to the operation of the operating unit, and the compensation value setting unit sets the compensation value according to the inclination of the center of gravity of the movable body relative to the direction of the gravitational acceleration detected by the detection unit, and the control unit performs compensation using the compensation value set in the compensation value setting unit, thereby proposing an impedance control device that performs impedance control related to the operation of the operating unit.

[0012] Form 3: In one or more embodiments of the present invention, the compensation value setting unit proposes an impedance control device that sets the compensation value based on the following formulas 1 and 2, using the following formula 1 when the Z axis of the set coordinates coincides with the gravitational acceleration direction, and using the following formula 2 when g(θ) when the Z axis of the set coordinates differs from the gravitational acceleration direction by θg.

number

number

[0013] Mode 4: In one or more embodiments of the present invention, an impedance control device is proposed in which g in the above equations 1 and 2 is a variable of the gravitational acceleration.

[0014] Form 5: In one or more embodiments of the present invention, an impedance control device is proposed in which the compensation value setting unit includes the magnitude of the gravitational acceleration as a parameter to set a compensation value in impedance control related to the operation of the operating unit.

[0015] Form 6: In one or more embodiments of the present invention, the control unit proposes an impedance control device that stops operation of the operation unit when the compensation value set in the compensation value setting unit exceeds an allowable value.

[0016] Mode 7: In one or more embodiments of the present invention, an impedance control device is proposed in which the movable body for which the control unit performs impedance control is a movable body having drive wheels including crawlers, a manipulator including a robot arm, or a movable body including an operating unit of a camera or a sensor.

[0017] Mode 8: In one or more embodiments of the present invention, the sensor is an impedance control device including a geomagnetic sensor, a tilt sensor, an IMU sensor, and an acceleration sensor.

[0018] Mode 9: In one or more embodiments of the present invention, an impedance control device is proposed for use while the movable body moves on an outdoor or indoor path including uneven areas with bumps and slopes. [Effects of the Invention]

[0019] According to one or more embodiments of the present invention, it is possible to suppress the effects of changes in gravitational acceleration and improve safety for movable bodies used while moving on outdoor or indoor running paths that include uneven areas with bumps and slopes. [Brief explanation of the drawings]

[0020] [Figure 1] 1 is a diagram illustrating a configuration of an impedance control device according to an embodiment of the present invention. [Figure 2] 1 is a diagram showing a configuration of an impedance control unit in an impedance control device according to an embodiment of the present invention; [Figure 3] 3A and 3B are diagrams for explaining modeling of impedance characteristics in the impedance control device according to the embodiment of the present invention. [Figure 4] FIG. 2 is a diagram illustrating a simulation model of an impedance control device according to an embodiment of the present invention. [Figure 5] 10 is a diagram showing the relationship between the reproducibility of the locus and the external force when the impedance is large in the impedance control device according to the embodiment of the present invention. FIG. [Figure 6] 10 is a diagram showing the relationship between the reproducibility of the locus and the external force when the impedance is medium in the impedance control device according to the embodiment of the present invention. FIG. [Figure 7] 10 is a diagram showing the relationship between the reproducibility of the locus and the external force when the impedance is small in the impedance control device according to the embodiment of the present invention. FIG. [Figure 8] 10 is a diagram showing the amount of compensation when the Z axis of the set coordinate system coincides with the direction of gravitational acceleration in the impedance control device according to the embodiment of the present invention. FIG. [Figure 9] 10 is a diagram showing the amount of compensation when the Z axis of the set coordinate system is in a direction different from the direction of gravitational acceleration by θg in the impedance control device according to the embodiment of the present invention. FIG. [Figure 10] 1A and 1B are diagrams showing the relationship between the reproducibility of the trajectory and the external force in an impedance control device according to an embodiment of the present invention, when (A) compensation is not performed, (B) compensation is performed, and (C) stiff control is performed. [Figure 11] 1A and 1B are diagrams showing the relationship between the reproducibility of the trajectory and external force in an impedance control device according to an embodiment of the present invention, in which (A) no compensation is performed, (B) compensation is performed taking into account the direction of gravitational acceleration, and (C) stiff control is performed. [Figure 12] 1A and 1B are diagrams showing the relationship between the reproducibility of the trajectory and external force in an impedance control device according to an embodiment of the present invention, in which (A) no compensation is performed, (B) compensation is performed taking into account the magnitude of gravitational acceleration, and (C) stiff control is performed. [Figure 13] FIG. 3 is a flowchart showing the processing of the impedance control device according to the embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0021] <Embodiment> The impedance control device 1 will be described with reference to FIGS. In the following, the impedance control device 1 according to this embodiment will be described taking as an example its use in a robot that is used outdoors or indoors including an uneven area.

[0022] <Configuration of Impedance Control Device 1> As shown in FIG. 1, the impedance control device 1 according to this embodiment includes a target position information generating unit 100, an impedance control unit 200, a torque control unit 300, a controlled object 400, and a sensor 500.

[0023] The target position information generating unit 100 generates target position information for each axis direction that defines the robot coordinate system. The target position information generated in the target position information generating unit 100 is transmitted to the impedance control unit 200, which will be described later.

[0024] <Configuration of Impedance Control Unit 200> As shown in FIG. 2, the impedance control unit 200 according to this embodiment includes a processor 210 and a memory 220.

[0025] The processor 210 performs position and force control to set the mechanical impedance (inertia, damping coefficient, stiffness, etc.) that occurs when an external force is applied to the robot's hand to a value that is suitable for the target task.

[0026] The memory 220 is configured from a ROM (Read Only Memory) or a RAM (Random Access Memory), and saves and stores programs and various data. The memory 220 is provided with a storage unit 221, which saves and stores, for example, a control program used by the processor, a database linking information on the tilt of the center of gravity of the robot relative to the direction of gravitational acceleration detected by a detection unit 211 described later with compensation values ​​set by a compensation value setting unit 212 described later, and other information including information on operating units that are controlled by force control among the operating units.

[0027] <Configuration of the processor 210> As shown in FIG. 2, the processor 210 includes a detection unit 211, a compensation value setting unit 212, and a control unit 213.

[0028] The detection unit 211 detects the tilt of the center of gravity of the robot relative to the direction of the gravitational acceleration detected by the sensor 500 . Examples of the sensor 500 include a geomagnetic sensor, an IMU (Inertial Measurement Unit), an inclinometer, a tilt sensor, and an inclinometer. The detection result in the detection unit 211 is transmitted to the compensation value setting unit 212, which will be described later.

[0029] The compensation value setting unit 212 sets a compensation value in impedance control relating to the operation of the operating unit. The compensation value setting unit 212 sets a compensation value in accordance with the inclination with respect to the direction of the gravitational acceleration detected by the detection unit 211 . The compensation value setting unit 212 sets a compensation value in impedance control relating to the operation of the operating unit, with the magnitude of the gravitational acceleration included in the parameters. The compensation value set in the compensation value setting unit 212 is transmitted to the control unit 213 .

[0030] The control unit 213 executes impedance control regarding the operation of the operation unit based on information including information about the operation unit stored in the storage unit 221 and information including information about the inclination relative to the direction of gravitational acceleration. If the compensation value set by compensation value setting section 212 exceeds the allowable value, control section 213 stops the operation of the operation section. The movable body for which the control unit 213 executes impedance control is a movable body having drive wheels including crawlers, a manipulator including a robot arm, and a movable body including a moving part such as a camera or a sensor.

[0031] Here, impedance control is a position and force control method for setting the mechanical impedance (inertia, damping coefficient, rigidity, etc.) that occurs when an external force is applied to the robot's hand to a value that is convenient for the intended task.

[0032] FIG. 3 is a diagram showing modeling of impedance characteristics, and FIG. 4 is a diagram showing an example of a simulation of impedance control. As shown in Figure 3, the mass M of the object, the spring constant K, the damping coefficient D, the position coordinate r, and the target coordinate r d and the external force f, it can be expressed by the following equation 3.

[0033]

number

[0034] Moreover, a general equation of motion can be expressed by the following equation 4. JPEG2025181531000005.jpg12157

[0035]

number

[0036] Furthermore, when numbers 3 and 4 are transformed using certain assumptions, we get the following number 5.

[0037]

number

[0038] Here, for the sake of simplicity, if we assume quasi-static operation with an extremely slow movement speed that reduces the influence of terms such as Coriolis force and centrifugal force, the first and second terms of equation 5 can be ignored, and ultimately the impedance control equation shown in equation 6 can be obtained.

[0039]

number

[0040] Based on the above, FIGS. 5 to 7 are diagrams showing the relationship between the magnitude of the impedance, the reproducibility of the locus, and the external force in the impedance control device 1 according to this embodiment. In the figure, thick vertical lines indicate obstacles, thin lines indicate the path to the target, and thick lines that partially overlap the thin lines indicate the path to the target when the obstacle is touched.

[0041] FIG. 5 shows the case where the values ​​of the viscosity coefficient Dd and the elastic coefficient Kd in Equation 3 are set to 2000 and the impedance is increased. In the case of FIG. 5, the reproducibility of the trajectory is the best compared to the cases of FIGS. 6 and 7, and the external force is also large.

[0042] FIG. 6 shows the case where the values ​​of the viscosity coefficient Dd and the elastic coefficient Kd in Equation 3 are set to 500 and the impedance is set to a medium level. In the case of FIG. 6, the reproducibility of the trajectory is medium compared to the cases of FIG. 5 and FIG. 7, and the external force is also medium.

[0043] FIG. 7 shows the case where the values ​​of the viscosity coefficient Dd and the elastic coefficient Kd in Equation 3 are set to 150, and the impedance is set to a small value. In the case of FIG. 7, the reproducibility of the trajectory is lower and the external force is smaller than in the cases of FIG. 5 and FIG.

[0044] The torque control unit 300 moves the controlled object 400 to a target position in accordance with the target torque τ calculated by the impedance control unit 200.

[0045] <Regarding the gravitational acceleration compensation term g(θ)> The gravitational acceleration compensation term g(θ) in the above equation 6 in the impedance control device 1 according to this embodiment will be described with reference to FIGS. The expression of g(θ) would normally be explained using vectors and arithmetic expressions for an actual complex model, but the content would be quite complex and difficult to understand. Therefore, in the following, for ease of understanding, the change in gravitational acceleration will be explained using calculation formulas and simulations assuming a vertical two-degree-of-freedom arm, and will be expressed only in terms of the deviation θg of the gravitational acceleration vector from the ideal angle and the magnitude of the gravitational acceleration. It should be noted that the vertical two-degree-of-freedom arm is used for convenience, and the following explanation can also be applied to other models.

[0046] FIG. 8 is a diagram showing a case where the Z axis of the set coordinates coincides with the direction of gravitational acceleration for the vertical two-degree-of-freedom arm shown in FIG. 4, and FIG. 9 is a diagram showing a case where the Z axis of the set coordinates differs from the direction of gravitational acceleration by θg. When the Z axis of the set coordinates coincides with the direction of gravitational acceleration, g(0) is expressed by the following equation 7, and when the Z axis of the set coordinates differs from the direction of gravitational acceleration by θg, g(θg) is expressed by the following equation 8.

[0047]

number

[0048]

number

[0049] Figure 10 shows the case where θg=0 degrees and g=9.8 m / s. 2 , and D=200 / K=500. Note that Figure 10(A) shows the relationship between the trajectory reproducibility and external force when gravitational acceleration compensation is not performed, Figure 10(B) shows the relationship between the trajectory reproducibility and external force when gravitational acceleration compensation is performed, and Figure 10(C) shows the relationship between the trajectory reproducibility and external force when stiff control is performed. Comparing FIG. 10(A) with FIG. 10(B), it is clear that the relationship between the trajectory reproducibility and the external force is significantly improved in FIG. 10(B).

[0050] Figure 11 shows the case where θg=45 degrees and g=9.8 m / s. 2 , D=200 / K=500, and the improvement effect of compensation for the influence of the direction of gravitational acceleration is shown. Note that Figure 11(A) shows the relationship between the trajectory reproducibility and external force when no gravitational acceleration compensation is performed, Figure 11(B) shows the relationship between the trajectory reproducibility and external force when gravitational acceleration compensation is performed at θg = 45 degrees, and Figure 11(C) shows the relationship between the trajectory reproducibility and external force when gravitational acceleration compensation is performed at θg = 0 degrees. Comparing Figures 11(A) to 11(C), it is clear that the relationship between the trajectory reproducibility and the external force is significantly improved in Figure 11(B) compared to Figure 11(A) as well as Figure 11(C).

[0051] Figure 12 shows the case where θg=0 degrees and g=9.8 m / s. 2 , D=200 / K=500, and the improvement effect of compensation for the influence of gravitational acceleration is shown. In addition, in Figure 12(A), the gravitational acceleration g is 9.8 m / s 2 The model compensated for the gravitational acceleration g=14.7m / s 2 Fig. 12(B) shows the relationship between the reproducibility of the trajectory and the external force when the robot is operated under the environment of gravitational acceleration g = 9.8 m / s 2The model compensated for the gravitational acceleration g=4.9m / s 2 Fig. 12(C) shows the relationship between the reproducibility of the trajectory and the external force when the robot is operated under the environment of gravitational acceleration g = 9.8 m / s 2 The model compensated for the gravitational acceleration g=9.8m / s 2 The graph shows the relationship between the reproducibility of the trajectory and the external force when the sensor is operated under the above environment. Looking at Figures 12(A) to 12(C), it can be seen that the relationship between the trajectory reproducibility and the external force is more effective in the case of Figure 12(C) than in the cases of Figure 12(A) or Figure 12(B). In the above case, g in Equations 3 and 4 is treated as a variable.

[0052] <Processing of Impedance Control Device 1> The processing of the impedance control device 1 according to this embodiment will be described with reference to FIG.

[0053] The detection unit 211 detects the tilt of the center of gravity of the robot as a movable body relative to the direction of gravitational acceleration (step S110). The detection result in the detection unit 211 is transmitted to the compensation value setting unit 212, which will be described later.

[0054] The compensation value setting unit 212 sets a compensation value in accordance with the inclination with respect to the direction of gravitational acceleration detected by the detection unit 211 (step S120). The compensation value set in the compensation value setting unit 212 is transmitted to the control unit 213 .

[0055] Control unit 213 executes impedance control regarding the operation of the operation unit based on information including information about the operation unit stored in storage unit 221 and information including information about the inclination relative to the gravitational acceleration direction (step S130). Furthermore, when the compensation value set by compensation value setting section 212 exceeds the allowable value, control section 213 stops the operation of the operation section.

[0056] <Actions and Effects> As described above, the impedance control device 1 of this embodiment is an impedance control device that controls a movable body having an operating unit, and is configured to include a memory unit 221 that stores information including information about the operating unit that is controlled by force control among the operating units, a sensor 500 that detects the direction of gravitational acceleration, a detection unit 211 that detects the inclination of the center of gravity of the movable body relative to the gravitational acceleration direction detected by the sensor 500, and a control unit 213 that performs impedance control regarding the operation of the operating unit based on information including information about the operating unit and information including information about the inclination of the center of gravity of the movable body relative to the gravitational acceleration direction. That is, the control unit 213 executes impedance control regarding the operation of the operating unit based on information including information regarding the operating unit and information including information regarding the tilt of the center of gravity of the movable body relative to the direction of gravitational acceleration. Therefore, the effects of changes in gravitational acceleration can be suppressed for movable bodies used while moving outdoors or on indoor running paths that include uneven areas with bumps and slopes, thereby improving safety.

[0057] The control unit 213 of the impedance control device 1 according to this embodiment includes a compensation value setting unit 212 that sets a compensation value in impedance control related to the operation of the operating unit. The compensation value setting unit sets the compensation value in accordance with the inclination of the center of gravity of the movable body relative to the direction of gravitational acceleration detected by the detection unit 211. The control unit 213 performs compensation using the compensation value set in the compensation value setting unit 212, and executes impedance control related to the operation of the operating unit. That is, the control unit 213 performs compensation using the compensation value set in the compensation value setting unit 212, and executes impedance control related to the operation of the operation unit. Therefore, the effects of changes in gravitational acceleration can be suppressed for movable bodies used while moving outdoors or on indoor running paths that include uneven areas with bumps and slopes, thereby improving safety.

[0058] The compensation value setting unit 212 of the impedance control device 1 according to this embodiment sets the compensation value based on the following formulas 1 and 2: when the Z axis of the set coordinates coincides with the direction of gravitational acceleration, the compensation value is set using the following formula 1; when the Z axis of the set coordinates differs from the direction of gravitational acceleration by θg, the compensation value is set using the following formula 2.

number

number

[0059] In the equations 1 and 2 of the impedance control device 1 according to this embodiment, g is a variable of gravitational acceleration. Therefore, even when not only the direction of the gravitational acceleration but also the magnitude of the gravitational acceleration changes, the influence of the change in the gravitational acceleration can be suppressed, thereby improving safety.

[0060] The compensation value setting unit 212 of the impedance control device 1 according to this embodiment sets a compensation value in impedance control relating to the operation of the operation unit, using parameters that include the magnitude of gravitational acceleration. That is, the compensation value in the impedance control relating to the operation of the operating part is set taking into consideration not only the inclination of the direction of gravitational acceleration but also the magnitude of the gravitational acceleration. Therefore, it is possible to sufficiently compensate for external factors such as changes in gravitational acceleration when the movable body moves. Therefore, the influence of changes in gravitational acceleration can be suppressed, and safety can be improved.

[0061] The control unit 213 of the impedance control device 1 according to this embodiment stops the operation of the operation unit when the compensation value set in the compensation value setting unit 212 exceeds the allowable value. That is, if the compensation value set by the compensation value setting unit 212 exceeds the allowable value, it is assumed that there is a problem with the attitude of the movable body. Therefore, if the compensation value set by the compensation value setting unit 212 exceeds the allowable value, the operation of the operation unit is stopped, thereby improving safety.

[0062] The movable bodies for which the control unit 213 of the impedance control device 1 according to this embodiment performs impedance control are movable bodies having drive wheels including crawlers, manipulators including robot arms, and movable bodies including operating parts such as cameras and sensors. That is, the impedance control device 1 according to this embodiment can be applied to various movable bodies. Therefore, the influence of changes in gravitational acceleration on various movable bodies can be suppressed, thereby improving safety.

[0063] The sensor 500 of the impedance control device 1 according to this embodiment includes a geomagnetic sensor, a tilt sensor, an IMU sensor, and an acceleration sensor. That is, the impedance control device 1 according to this embodiment can be configured without being limited to a specific sensing element. Therefore, the effects of changes in gravitational acceleration can be suppressed for movable bodies used while moving outdoors or on indoor running paths that include uneven areas with bumps and slopes, thereby improving safety.

[0064] The impedance control device 1 according to this embodiment is used for a movable body that is used while moving on an outdoor or indoor running path that includes an uneven area with bumps and slopes. Therefore, the effects of changes in gravitational acceleration can be suppressed for movable bodies used while moving outdoors or on indoor running paths that include uneven areas with bumps and slopes, thereby improving safety.

[0065] The impedance control device 1 of the present invention can be realized by recording the processing of the processor 210 on a recording medium that can be read by a computer system, and having the processor 210 read and execute the program recorded on this recording medium. The computer system here includes hardware such as an OS and peripheral devices.

[0066] Furthermore, if a WWW (World Wide Web) system is used, the "computer system" also includes the homepage providing environment (or display environment). The program may also be transmitted from a computer system that stores the program in a storage device or the like to another computer system via a transmission medium or by transmission waves in the transmission medium. Here, the "transmission medium" that transmits the program refers to a medium that has the function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line.

[0067] The program may also be for realizing part of the above-mentioned functions. Furthermore, the above-mentioned functions may be realized in combination with a program already recorded in the computer system, that is, a so-called differential file (differential program).

[0068] The above has described in detail an embodiment of the present invention with reference to the drawings, but all impedance control devices that can be implemented by a person skilled in the art by making appropriate design modifications based on the impedance control device 1 described above as an embodiment of the present invention also fall within the technical scope of the present invention as long as they include the gist of the present invention. Within the scope of the concept of the present invention, a person skilled in the art may conceive of various modifications and alterations, and it is understood that these modifications and alterations also fall within the technical scope of the present invention. For example, any embodiment in which a person skilled in the art has appropriately added or deleted components or modified the design, or added or omitted steps or modified conditions, is included within the technical scope of the present invention as long as it contains the gist of the present invention.

[0069] Furthermore, other effects and advantages brought about by the aspects described in this embodiment that are clear from the description in this specification or that can be appropriately thought of by a person skilled in the art are naturally understood to be brought about by the present invention. Various inventions can be formed by appropriately combining the multiple components disclosed in the above embodiments. For example, some components may be omitted from all the components shown in the embodiment. Furthermore, components from different embodiments may be combined as appropriate. [Explanation of symbols]

[0070] 1; Impedance control device 100;Target position information generation unit 200: Impedance control section 210;processor 211;Detection unit 212: Compensation value setting unit 213;Control section 220;Memory 300: Torque control section 400;Control object

Claims

1. An impedance control device that controls a movable body having an operating unit, a storage unit that stores information including information about the operation units that are controlled by force control; a sensor for detecting the direction of gravitational acceleration; a detection unit that detects the inclination of the center of gravity of the movable body with respect to the detected direction of the gravitational acceleration; a control unit that executes impedance control regarding the operation of the operation unit based on information including information about the operation unit and information including information about the tilt of the center of gravity of the movable body with respect to the gravitational acceleration direction; an impedance control device comprising:

2. the control unit includes a compensation value setting unit that sets a compensation value in impedance control related to the operation of the operation unit, The impedance control device described in claim 1, wherein the compensation value setting unit sets a compensation value according to the inclination of the center of gravity of the movable body with respect to the direction of the gravitational acceleration detected by the detection unit, and the control unit performs compensation using the compensation value set by the compensation value setting unit and executes impedance control regarding the operation of the operating unit.

3. 3. The impedance control device according to claim 2, wherein the compensation value setting unit sets the compensation value based on the following formulas 1 and 2: when the Z axis of the set coordinates coincides with the direction of the gravitational acceleration, the compensation value is set using the following formula 1; and when g(θ) differs from the direction of the gravitational acceleration by θg, the compensation value is set using the following formula 2. [Equation 1] Here, B1 and B2 are coefficients calculated from the respective dynamic parameters. [Equation 2] Here, B1 and B2 are coefficients calculated from the respective dynamic parameters.

4. 4. The impedance control device according to claim 3, wherein g in said equations 1 and 2 is a variable of said gravitational acceleration.

5. 5. The impedance control device according to claim 4, wherein the compensation value setting unit sets a compensation value in impedance control relating to the operation of the operation unit by including the magnitude of the gravitational acceleration as a parameter.

6. 3. The impedance control device according to claim 2, wherein the control unit stops the operation of the operation unit when the compensation value set by the compensation value setting unit exceeds an allowable value.

7. 2. The impedance control device according to claim 1, wherein the movable body for which the control unit performs impedance control is a movable body having drive wheels including crawlers, a manipulator including a robot arm, or a movable body including the operating unit of a camera or a sensor.

8. The impedance control device according to claim 1 , wherein the sensors include a geomagnetic sensor, a tilt sensor, an IMU sensor, and an acceleration sensor.

9. 2. The impedance control device according to claim 1, wherein the movable body is used while moving on an outdoor path or an indoor path including an uneven area with bumps and slopes.

Images