ELECTROMECHANICALLY COUNTERBALANCED HUMANOID ROBOTIC SYSTEM

• US 20100243344A1
• Filed: 11/25/2009
• Published: 09/30/2010
• Est. Priority Date: 09/25/2006
• Status: Abandoned Application

• Current Assignee: Board of Trustees of the Leland Stanford Junior University (Stanford Management Co.)
• Original Assignee: Board of Trustees of the Leland Stanford Junior University (Stanford Management Co.)
• Inventors: Berger, Eric, Wyrobek, Keenan A., Salisbury, J. Kenneth JR.
• Application Number:
  US12/626,187
• Publication Number:
  US 20100243344A1
• Time in Patent Office: Days
• US Class Current: 180/21
• CPC Class Codes: B25J 19/0016 using springs
• CPC Class Codes: B25J 5/007 mounted on wheels
• CPC Class Codes: Y10S 901/01 Mobile robot
• CPC Class Codes: Y10S 901/48 Counterbalance
• CPC Class Codes: Y10T 74/20305 Robotic arm

Abstract

Systems and methods related to construction, configuration, and utilization of humanoid robotic systems and aspects thereof are described. A system may include a mobile base, a spine structure, a body structure, and at least one robotic arm, each of which is movably configured to have significant human-scale capabilities in prescribed environments. The one or more robotic arms may be rotatably coupled to the body structure, which may be mechanically associated with the mobile base and spine such that it may be deflectably elevated and rolled relative to the base simultaneously and independently. Aspects of the one or more arms may be counterbalanced with one or more spring-based counterbalancing mechanisms which facilitate backdriveability and payload features.

Claims

1. A humanoid robotic system comprising:

a. a mobile base comprising a base frame and a plurality of wheels rotatably coupled to the base frame and configured to controllably navigate floors through contact with a generally planar floor surface;

b. an elongate spine structure fixedly coupled to the mobile base and projecting from said mobile base along a longitudinal axis of the elongate spine structure that is substantially perpendicular from the plane of the generally planar floor surface;

c. a body structure slidably and rotatably coupled to the elongate spine structure, the body structure having spine interface configured to facilitate rolling of the body structure about a roll axis substantially coincident with the longitudinal axis of the elongate spine structure, as well as simultaneous and independent axial defection of the body relative to the mobile base in a direction substantially parallel to the longitudinal axis of the elongate spine structure; and

d. at least one robotic arm rotatably coupled to the body structure.

2. The robotic system of claim 1, wherein the mobile base comprises a battery-based power supply system configured to operate all aspects of the robotic system in an extended self-contained mode, without additional external power connectivity, when charged.

3. The robotic system of claim 1, wherein the mobile base comprises at least three wheel-based floor interfaces, two of which are independently actuated by a wheel drive motor, the remainder of which are passively rotatable.

4. The robotic system of claim 1, wherein the elongate spine structure comprises a body structure elevator cart which is controllably repositionable relative to a length of the elongate spine, and which is rotatably coupled to the body structure.

5. The robotic system of claim 4, wherein the body structure may be electromechanically rolled about the body structure elevator cart to which it is coupled via a body roll actuator coupled to the body structure, the roll actuator being coupled to a body roll actuator drive pulley which is coupled to a pulley comprising the body structure elevator cart by a flexible recirculatory drive member.

6. The robotic system of claim 4, wherein the body structure elevator cart may be electromechanically repositioned relative to the length of the elongate spine via a body elevator actuator coupled to the mobile base, the body elevator actuator being coupled to a body elevator drive pulley which is coupled to the body structure elevator cart by a tension member.

7. The robotic system of claim 1, comprising two robotic arms rotatably coupled to the body structure.

8. The robotic system of claim 1, wherein the at least one robotic arm comprises a force-controlled, backdriveable arm.

9. The robotic system of claim 8, wherein the at least one robotic arm has a payload of approximately 2 kilograms.

10. The robotic system of claim 1, wherein the at least one robotic arm comprises a spring-based counterbalancing mechanism configured to utilize one or more springs to compensate for gravitational forces associated with one or more portions of the at least one robotic arm.

11. The robotic system of claim 10, wherein the at least one robotic arm comprises a forearm portion, an upper arm portion, a first spring, and a second spring, and wherein the first spring is configured to compensate for gravitational forces associated with the mass of the forearm portion, and the second spring is configured to compensate for gravitational forces associated with the mass of the upper arm portion.

12. The robotic system of claim 10, wherein at least one of the one or more springs is configured to be controllably and electromechanically adjusted utilizing an actuator.

13. The robotic system of claim 10, wherein at least one of the one or more springs is a compression spring.

14. The robotic system of claim 10, wherein the at least one robotic arm comprises a proximal support structure rotatably coupled to the body structure, the proximal support structure rotatably coupled to a robotic arm upper arm portion, which is rotatably coupled to a robotic forearm portion, and wherein the proximal support structure substantially contains and is coupled to the spring-based counterbalancing mechanism.

15. A robotic arm system, comprising:

a. a proximal support structure;

b. an arm comprising an upper arm portion and a forearm portion;

the upper arm portion having a proximal and a distal end, the proximal end being rotatably coupled to the proximal support structure;

the forearm portion having a proximal and a distal end, the proximal end being rotatably coupled to the distal end of the upper arm portion; and

c. an electromechanically adjustable spring-based counterbalancing mechanism comprising a spring intercoupled between the proximal support structure and the arm and configured to counterbalance loads imparted to the arm.

16. The robotic arm system of claim 15, wherein the proximal end of the upper arm portion comprises a shoulder interface portion configured to be rotatably coupled to the proximal structure to allow shoulder flexion rotation about an axis substantially perpendicular to a longitudinal axis of the proximal support structure.

17. The robotic arm system of claim 16, wherein the proximal support structure is rotatably coupled to a parent structure such that the proximal support structure may be rotated about its longitudinal axis to provide a panning rotation of the shoulder interface relative to the parent structure, independently of the shoulder flexion rotation.

18. The robotic arm system of claim 16, wherein the spring is intercoupled between the proximal support structure and the shoulder interface portion by a tension member, and wherein the spring is configured to apply a counterbalancing torque about the shoulder interface to prevent shoulder flexion based at least in part upon gravitational loads imparted upon the upper arm portion.

19. The robotic arm system of claim 15, further comprising a forearm counterbalancing linkage comprising a proximal member extending from and being rotatably coupled to the proximal end of the upper arm portion, the proximal member also being coupled to the forearm portion and being configured such that a longitudinal axis of the proximal member remains parallel to a longitudinal axis of the forearm portion.

20. The robotic arm system of claim 19, wherein the forearm counterbalancing linkage comprises a proximal member pulley rotatably coupled to the proximal end of the upper arm portion and fixedly coupled to the proximal member, and wherein the proximal end of the forearm portion comprises a timing pulley configured to rotate about an elbow flexion axis defined by the rotatable coupling between the proximal end of the forearm portion and the distal end of the upper arm portion when the upper arm portion and forearm portion are rotated relative to each other, and wherein a timing belt is routed around each of the proximal member pulley and timing pulley and across the upper arm portion to retain the parallel orientation of the proximal member and the longitudinal axis of the forearm portion.

21. The robotic arm system of claim 20, wherein the spring is intercoupled between the proximal support structure and the proximal member, and wherein the spring is configured to apply a counterbalancing torque about the elbow flexion axis to prevent rotation of the forearm portion at the elbow flexion axis based at least in part upon gravitational loads imparted upon the forearm portion.

22. The robotic arm system of claim 15, further comprising a gripper rotatably coupled to the distal end of the forearm portion.

23. The robotic arm system of claim 22, wherein the gripper is configured to roll and flex about a wrist axis relative to the distal end of the forearm portion.

24. The robotic arm system of claim 16, wherein the shoulder interface portion of the upper arm portion is rotatably coupled to the remainder of the upper arm portion, and configured to allow for a shoulder roll rotation about a longitudinal axis of the upper arm portion.

25. The robotic arm system of claim 15, wherein the spring is constrained in controlled compression.

26. The robotic arm system of claim 15, wherein the spring is constrained in controlled tension.

27. The robotic arm system of claim 15, wherein the spring-based counterbalancing mechanism comprises a first spring intercoupled between the proximal support structure and the forearm portion, and a second spring intercoupled between the proximal support structure and the upper arm portion, wherein both springs are electromechanically adjustable.

28. The robotic arm system of claim 15, wherein the spring is electromechanically adjusted with a cable operably coupled to a motor configured to controllably add or decrease loads applied to the spring.

29. A method of operating a robotic arm, comprising:

a. providing a robotic arm system comprising a proximal support structure and an arm having an upper arm portion and a forearm portion;

the upper arm portion having a proximal and a distal end, the proximal end being rotatably coupled to the proximal support structure;

the forearm portion having a proximal and a distal end, the proximal end being rotatably coupled to the distal end of the upper arm portion; and

b. electromechanically adjusting a spring-based counterbalancing mechanism comprising a spring intercoupled between the proximal support structure and the arm to counterbalance loads imparted to the arm.

30. The method of claim 29, wherein the spring-based counterbalancing mechanism is intercoupled between the proximal support structure and the proximal end of the upper arm portion, and wherein electromechanically adjusting comprises actuating a motor coupled to the spring by a tensioning element.

31. The method of claim 29, wherein the spring-based counterbalancing mechanism is intercoupled between the proximal support structure and a proximal member extending from and being rotatably coupled to the proximal end of the upper arm portion, the proximal member being coupled to the forearm portion by a linkage configured such that a longitudinal axis of the proximal member remains parallel to a longitudinal axis of the forearm portion, and wherein electromechanically adjusting comprises actuating a motor coupled to the spring by a tensioning element.

32. The method of claim 29, wherein electromechanically adjusting comprises changing the tension on a compression spring by actuating a motor coupled to the spring by a tensioning element.

33. The method of claim 29, wherein electromechanically adjusting comprises changing the tension on a tension spring by actuating a motor coupled to the spring by a tensioning element.