Robot device and method of controlling robot device operation

• US 20040034449A1
• Filed: 06/10/2003
• Published: 02/19/2004
• Est. Priority Date: 02/21/2001
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Yokono, Jun, Fujita, Masahiro, Hugel, Vincent
• Granted Patent: US 6,865,446 B2
• Time in Patent Office: Days
• US Class Current: 700/245
• CPC Class Codes: B25J 9/1633 compliant, force, torque control, e.g. combined with position control

Abstract

A robot apparatus is provided which includes body portions such as a head block (4), leg blocks (3A to 3D), an actuator (25) to actuate the body portions and a CPU (10) to supply a control signal to the actuator (25). In this apparatus, information about an external force applied to the apparatus, such as the position, magnitude, direction, etc. of the external force, is computed on the basis of changes of the control signal supplied from the CPU (10) to drive the actuator (25) and a signal supplied as a response to the CPU (10) when the actuator (25) is driven. The external force information is supplied to the CPU (10) and used as information for selection of a behavior and emotion of the robot apparatus and the next behavior of the apparatus. Thus, in the robot apparatus, since the external force information is computed on the basis of an output from the CPU (10) and outputs from the actuator (25) and a potentiometer (26), so an external force can be detected by the use of existing devices and no dedicated sensors have to be additionally provided.

Claims

1. A robot apparatus comprising:

an actuator whose motion is controlled with a control signal;

a controlling means for outputting the control signal which causes the actuator do a predetermined motion; and

means for detecting an external force on the basis of a change shown by the control signal when the external force is applied to the actuator.

2. The apparatus as set forth in claim 1, wherein the external force detecting means detects an external force on the basis of the control signal change according to a processing program.

3. The apparatus as set forth in claim 1, wherein the external force detecting means detects the direction and/or magnitude of the external force.

4. The apparatus as set forth in claim 1, wherein the controlling means controls the actuating means to autonomously operate when the external force detecting means detects a predetermined external force.

5. The apparatus as set forth in claim 1, wherein:

the control signal is a PWM (pulse width modulation) pulse having the width thereof modulated by data; and

the external force detecting means detects an external force on the basis of a change in width shown by the PWM pulse when the external force is applied to the actuating means.

6. The apparatus as set forth in claim 1, further comprising:

a joint mechanism actuated by the actuator;

a motion controlling means for specifying, to the actuating means, an amount of motion for actuating the joint mechanism; and

means for detecting an actual amount of motion the actuator has done for actuating the joint mechanism;

the external force detecting means detecting whether or not an external force has been applied to the actuator, on the basis of the amount of motion specified to the actuator by the motion controlling means and the actual amount of motion having been done by the actuator and detected by the motion detecting means.

7. The apparatus as set forth in claim 6, wherein the joint mechanism is a shoulder joint mechanism of a leg block.

8. The apparatus as set forth in claim 6, wherein the actuator is to actuate the leg block in the pitch direction.

9. The apparatus as set forth in claim 6, further comprising means for providing a predetermined tumbling prevention when an external force is detected by the external force detecting means.

10. The apparatus as set forth in claim 6, further comprising:

a plurality of leg blocks actuated in predetermined patterns, respectively; and

means for computing a distance from each side of a polygon defined by connecting landing points of landing ones of the plurality of leg blocks to a projected point, on a walking surface, of the center of gravity of the robot apparatus;

the external force detecting means determining whether or not an external force is applied to the robot apparatus, on the basis of the specified and actual amounts of motion, and the distance from each side of the polygon to the projected point, computed by the distance computing means.

11. A method of controlling the operation of a robot apparatus, comprising steps of:

controlling the motion of an actuator thereof with a control signal; and

detecting an external force to the robot apparatus on the basis of a change shown by the control signal when the external force is applied to the robot apparatus.

12. The method as set forth in claim 11, wherein in the external force detecting step, there is detected an external force on the basis of the control signal change according to a processing program.

13. The method as set forth in claim 11, wherein in the external force detecting step, there are detected the direction and/or magnitude of the external force.

14. The method as set forth in claim 11, wherein:

the control signal is a PWM (pulse width modulation) pulse having the width thereof modulated by data; and

in the external force detecting step, there is detected an external force on the basis of a change in width shown by the PWM pulse when the external force is applied to the actuating means.

15. The method as set forth in claim 11, further comprising steps of:

specifying, to the actuator, an amount of motion for actuating a joint mechanism; and

detecting an actual amount of motion the actuator has done for actuating the joint mechanism;

in the external force detecting step, there being detected whether or not an external force has been applied to the actuator, on the basis of the amount of motion specified to the actuator in the motion controlling step and the actual amount of motion made by the actuator and detected in the motion detecting step.

16. The method as set forth in claim 15, wherein the joint mechanism is a shoulder joint mechanism of a leg block.

17. The method as set forth in claim 15, wherein the actuator is to actuate the leg block in the pitch direction.

18. The method as set forth in claim 15, further comprising a step of providing a predetermined tumbling prevention when an external force is detected in the external force detecting step.

19. The method as set forth in claim 15, further comprising steps of:

having the robot apparatus walk by actuating a plurality of leg blocks in predetermined patterns, respectively; and

computing a distance from each side of a polygon defined by connecting landing points of landing ones of the plurality of leg blocks to a projected point, on a walking surface, of the center of gravity of the robot apparatus;

in the external force detecting step, there being determined whether or not an external force is applied to the robot apparatus, on the basis of the specified and actual amounts of motion, and the distance from each side of the polygon to the projected point, computed by the distance computing means.

20. An external force detecting apparatus comprising:

means for actuating each portion of a robot apparatus;

a controlling means for specifying, to the actuating means, an amount of motion for actuating the portion;

means for detecting an actual amount of motion the actuating means has done; and

means for determining, on the basis of the specified and actual amounts of motion, whether or not an external force has been applied to the robot apparatus.

21. An external force detecting method comprising steps of:

specifying, to means for actuating each portion of a robot apparatus, an amount of motion for actuating the portion;

detecting an actual amount of motion the actuating means has done for actuating the portion; and

determining whether or not an external force has been applied to the robot apparatus, on the basis of the specified and actual amounts of motion.

22. A program causing a robot apparatus to:

control the motion of an actuator thereof with a control signal; and

detect an external force to the robot apparatus on the basis of a change shown by the control signal when the external force is applied to the robot apparatus.

23. The program as set forth in claim 22, wherein in the external force detecting step, there is detected an external force on the basis of the control signal change according to a processing program.

24. The program as set forth in claim 22, wherein:

the control signal is a PWM (pulse width modulation) pulse having the width thereof modulated by data; and

in the external force detecting step, there is detected an external force on the basis of a change in width shown by the PWM pulse when the external force is applied to the actuating means.

25. A recording medium having recorded therein a program which causes a robot apparatus to:

control the motion of an actuator thereof with a control signal; and

detect an external force to the robot apparatus on the basis of a change shown by the control signal when the external force is applied to the robot apparatus.

26. The recording medium as set forth in claim 25, wherein in the external force detecting step, there is detected an external force on the basis of the control signal change according to a processing program.

27. The recording medium as set forth in claim 25, wherein:

the control signal is a PWM (pulse width modulation) pulse having the width thereof modulated by data; and

in the external force detecting step, there is detected an external force on the basis of a change in width shown by the PWM pulse when the external force is applied to the actuating means.