Device and method for measuring the position of animate links

• US 6,497,672 B2
• Filed: 05/05/2000
• Issued: 12/24/2002
• Est. Priority Date: 10/24/1997
• Status: Expired due to Term

• Current Assignee: Immersion Corporation
• Original Assignee: Virtual Technologies, Inc. (Immersion Corporation)
• Inventors: Kramer, James F.
• Primary Examiner(s): Shaver, Kevin
• Assistant Examiner(s): WINGOOD, PAMELA LYNN
• Application Number:
  US09/565,730
• Publication Number:
  US 20010020140A1
• Time in Patent Office: 963 Days
• Field of Search: 600/587, 600/595
• US Class Current: 600/595
• CPC Class Codes: A61B 2562/0261 Strain gauges
• CPC Class Codes: A61B 34/70 Manipulators specially adapted for use in surgery
• CPC Class Codes: A61B 5/1071 measuring angles, e.g. using goniometers A61B5/1123 takes precedence
• CPC Class Codes: A61B 5/1116 Determining posture transitions
• CPC Class Codes: A61B 5/4528 Joints A61B5/4533, A61B5/4538 take precedence
• CPC Class Codes: A61B 5/6825 Hand
• CPC Class Codes: A61B 5/6826 Finger
• CPC Class Codes: A61B 5/6831 Straps, bands or harnesses
• CPC Class Codes: B25J 13/02 Hand grip control means handles or pedals for crane control B66C13/56; for measuring the force applied to control members G01L5/22; hand-held casings for switching devices, e.g. joy-sticks H01H9/0214
• CPC Class Codes: B25J 9/0006 Exoskeletons, i.e. resembling a human figure
• CPC Class Codes: G06F 3/011 Arrangements for interaction with the human body, e.g. for user immersion in virtual reality blind teaching G09B21/00
• CPC Class Codes: G06F 3/014 Hand-worn input/output arrangements, e.g. data gloves

Abstract

An exoskeleton device is provided for measuring positions of links and angles of joints of an animate body, where the body comprises a plurality of links joined by intervening joints. The device is affixed at a first mobile terminus of said animate body and a second fixed terminus, having device links displaced from animate links, where the device links are connected by device joints and having sensor means for measuring the angle of the device joints. Using the signals from the sensor means, one can determine the position of the terminal device link and based on knowledge of the animate body structure, calculate the animate angle joints.

Claims

1. A method for measuring the relative placement of two animate links separated by at least one animate joint, said method comprising:

providing a device kinematic chain having;

two terminal device links, each adapted to engage a respective one of the animate links;

a third device link between said two terminal device links; and

at least three device joints joined by said terminal device links and said third device link, with at least one of said device joints being displaced away from the animate links in use, at least two of said device joints being sensing joints on opposing ends of said third device link, wherein the number of said sensing joints is at least sufficient to determine the relative placement of the two animate links;

measuring the angle of each of said sensing joints;

transmitting the angle measurement for each of said sensing joints as an electrical signal to a signal processor; and

determining the relative placement of the two animate links from said electrical signals.

2. A method according to claim 1, comprising determining the relative placement of the two animate links using inverse kinematics of the animate links and the at least one animate joint.

3. A method according to claim 1, wherein the two animate links are separated by at least one intermediate animate link, and further comprising determining the relative placement of the at least one intermediate animate link using inverse kinematics on the animate links and the at least one animate joint.

4. A method according to claim 1, comprising determining the relative placement of the two animate links by:

calculating the relative placement of said two terminal device links from said electrical signals; and

calculating at least one animate joint angle using the relative placement of said two terminal device links.

5. A method according to claim 1, wherein said determining considers the placement of a device link on an animate link.

6. A method according to claim 1, wherein said device kinematic chain comprises at least three sensing joints.

7. A method according to claim 1, wherein said device kinematic chain comprises at least four device joints.

8. A method according to claim 7, wherein the axes of at least three device joints are parallel.

9. A method according to claim 1, further comprising measuring the placement of a third animate link.

23. A method according to claim 1, wherein said device links are each affixed to an animate link by an attachment.

10. A method for measuring the relative placement of two terminal animate links separated by at least one animate joint, the method comprising:

providing a device kinematic chain having;

two terminal device links, each adapted to engage a respective one of the terminal animate links;

an intermediate device link; and

at least three device joints joined by said intermediate device link and said terminal device links, with at least one device joint being displaced away from the terminal animate links in use, at least two of said device joints being sensing joints attached at opposing ends of said intermediate device link, and at least one of said device joints being a non-sensing joint, wherein the number of said sensing joints is at least sufficient to determine the relative placement of the two terminal animate links;

measuring the angle of each of said sensing joints;

transmitting the angle measurement for each of said sensing joints as an electrical signal to a signal processor; and

determining the relative placement of the two animate links from said electrical signals.

24. A method according to claim 10, wherein said device links are each affixed to an animate link by an attachment.

11. A method for measuring the relative placement of two animate links separated by at least one animate joint, the method comprising:

providing a device kinematic chain having three sensing joints joining four device links, two of said four device links being adapted to engage a respective one of the animate links;

measuring the angle of each of said sensing joints;

transmitting the angle measurement for each of said sensing joints as an electrical signal to a signal processor; and

determining the relative placement of the two animate links from said electrical signals.

12. A method according to claim 11, wherein the two animate links are separated by at least one intermediate animate link, and further comprising determining the relative placement of the at least one intermediate animate link using inverse kinematics on the animate links and the at least one animate joint.

25. A method according to claim 11, wherein said device links are each affixed to an animate link by an attachment.

26. A method according to claim 11, wherein said four device links include the terminal device links.

13. A method for measuring the relative placement of two animate links separated by at least one animate joint, the method comprising:

providing a device kinematic chain having;

two terminal device links, each adapted to engage a respective one of the animate links;

intermediate device links; and

at least four device joints having parallel axes and joined by said intermediate device links and said terminal device links, with at least one device joint displaced from the surface of the animate links, at least two of said device joints being sensing device joints attached to opposing ends of an intermediate device link, the number of device joints which are sensing device joints being at least sufficient to determine the relative placement of the two animate links;

measuring the angle of each of said sensing device joints;

transmitting the angle measurement for each of said sensing device joints as an electrical signal to a signal processor; and

determining the relative placement of the two animate links from said electrical signals.

27. A method according to claim 13, wherein said device links are each affixed to an animate link by an attachment.

14. A method for measuring the relative placement of two terminal animate links separated by at least two animate joints of at least one animate kinematic chain, the animate kinematic chain comprising a portion of a hand including at least a portion of a finger, said method comprising:

employing a device kinematic chain having terminal device links, each engaging a terminal animate link, and intermediate device links, said device kinematic chain comprising a plurality of device joints with at least one device joint displaced away from said animate links and said device joints being joined by said terminal device links and said intermediate device links, where the number of device joints is at least three comprising at least two sensing device joints on opposite ends of an intermediate device link, where the number of sensing device joints is sufficient to determine the relative placement of said two terminal animate links;

measuring the angle of each of said sensing device joints;

transmitting the angle measurement for each of said sensing device joints as an electrical signal to a signal processor; and

determining the relative placement of the two terminal animate links of the portion of the hand from said electrical signals.

15. A method according to claim 14, wherein the terminal animate links are the distal phalanx of the finger and the metacarpus of the hand.

16. A method according to claim 14, wherein said method comprises measuring a plurality of the animate kinematic chains.

28. A method according to claim 14, wherein said terminal device links are each affixed to a terminal animate link by an attachment.

17. A device for measuring the relative placement of two animate links separated by at least one animate joint, said device comprising:

at least one device kinematic chain comprising;

at least three device joints comprising at least two sensing joints, said sensing joints outputting electrical signals related to the angle of said sensing device joint; and

at least two device links including two device links each capable of engaging a respective animate link, said device links joining said device joints, wherein two sensing joints are attached on opposite ends of a device link;

a signal transmission means for transmitting said electrical signals; and

a signal processor receiving said electrical signals and determining the relative placement of the two animate links.

18. A device according to claim 17, wherein said device comprises at least two device kinematic chains.

19. A device according to claim 18, wherein two of said kinematic chains share a common link.

20. A device according to claim 17, wherein said device kinematic chain comprises at least three sensing joints.

21. A device according to claim 17, wherein said device kinematic chain comprises at least four device joints.

22. A device according to claim 21, wherein the axes of at least three device joints are parallel.

29. A device according to claim 17, further comprising two attaching means for individual attachment to the two animate links.

30. A device according to claim 29 wherein said device links are capable of engaging the animate links through the attaching means.

31. A device according to claim 17 further comprising at least one intermediate device link between said device links.

32. A method for measuring the relative placement of two animate links separated by at least one animate joint, said method comprising:

providing a device kinematic chain having;

intermediate device links and two terminal device links, each of said terminal device links adapted to engage a respective one of the animate links; and

at least three sensing device joints, joined by said intermediate device links and said terminal device links;

measuring the angle of each of said sensing device joints;

transmitting the angle measurement for each of said sensing device joints as an electrical signal to a signal processor; and

determining the relative placement of the two animate links from said electrical signals.

33. A method according to claim 32, wherein said device links are each affixed to an animate link by an attachment.

34. A device for measuring the relative placement of two animate links separated by at least one animate joint, said device comprising:

at least one device kinematic chain comprising;

intermediate device links;

at least three sensing device joints joined by said intermediate device links, said sensing device joint producing electrical signals related to the angle of said sensing device joint; and

two terminal device links each capable of engaging a respective animate link, said terminal device links joined to a respective one of two of said sensing joints;

a signal transmission means for transmitting said electrical signals; and

a signal processing means receiving said electrical signals to determine the relative placement of the two animate links.

35. A device according to claim 34, wherein the device kinematic chain comprises at least four device joints.

36. A device according to claim 34, wherein two sensing device joints are on opposing ends of one of said intermediate device links.