Control device and system for controlling an actuated prosthesis

• US 20060122710A1
• Filed: 11/09/2005
• Published: 06/08/2006
• Est. Priority Date: 08/22/2002
• Status: Active Grant

• Current Assignee: Stephane Bedard
• Original Assignee: Stephane Bedard
• Inventors: Bedard, Stephane
• Granted Patent: US 7,867,284 B2
• Time in Patent Office: Days
• US Class Current: 623/24
• CPC Class Codes: A61F 2/644 of the single-bar or multi-bar linkage type
• CPC Class Codes: A61F 2/6607 Ankle joints
• CPC Class Codes: A61F 2/70 electrical
• CPC Class Codes: A61F 2002/607 Lower legs
• CPC Class Codes: A61F 2002/6614 Feet
• CPC Class Codes: A61F 2002/701 operated by electrically controlled means, e.g. solenoids or torque motors
• CPC Class Codes: A61F 2002/704 computer-controlled, e.g. robotic control
• CPC Class Codes: A61F 2002/705 Electromagnetic data transfer for implantable prostheses A61F2250/0002
• CPC Class Codes: A61F 2002/762 for measuring dimensions, e.g. a distance
• CPC Class Codes: A61F 2002/7625 for measuring angular position
• CPC Class Codes: A61F 2002/763 for measuring spatial position, e.g. global positioning system [GPS]
• CPC Class Codes: A61F 2002/7635 for measuring force, pressure or mechanical tension
• CPC Class Codes: A61F 2002/7645 for measuring torque, e.g. hinge or turning moment, moment of force
• CPC Class Codes: A61F 2002/7685 located on natural or sound-site limbs, e.g. comparison measuring means

Abstract

A device and system for controlling an actuated prosthesis. The device includes a data signal input for each of the main artificial proprioceptors. Also, means for obtaining a first and a second derivative signal for at least some of the data signals, and means for obtaining a third derivative signal for at least one of the data signals. A set of first state machines, and means for generating the phase of locomotion portion using the states of the main artificial proprioceptors, and a second state machine as also included. The system includes a plurality of main artificial proprioceptors as well as means for obtaining a first and a second derivative signal for at least some of the data signals, and means for obtaining a third derivative signal for at least one of the data signals. Also, a set of first state machines, a second state machine, means for storing a lookup table, means for determining actual coefficient values from the lookup table, means for calculating at least one dynamic parameter value of the actuated prosthesis using the lookup table and at least some of the data signals, and means for converting the dynamic parameter value into an output signal to control the actuated prosthesis.

Claims

1. A device for determining a portion of locomotion and a phase of locomotion portion in view of controlling an actuated prosthesis in real time using a plurality of main artificial proprioceptors, the device comprising:

a data signal input for each of the main artificial proprioceptors;

means for obtaining a first and a second derivative signal for at least some of the data signals;

means for obtaining a third derivative signal for at least one of the data signals;

a set of first state machines, the first state machines being used to select one state among a plurality of possible states for each artificial proprioceptor with the corresponding data and derivative signals;

means for generating the phase of locomotion portion using the states of the main artificial proprioceptors; and

a second state machine, the second state means being used to select the portion of locomotion among a plurality of possible portions of locomotion using events associated to the data signals.

2. The device according to claim 1, further comprising:

a first output to output a first output signal indicative of the state of the main artificial proprioceptors;

a second output to output a second output signal indicative of the phase of locomotion portion; and

a third output to output a third output signal indicative of the portion of locomotion.

3. The device according to claim 1, further comprising:

means for pre-processing the data signals before obtaining the derivative signals.

4. The device according to claim 3, wherein the means for pre-processing the data signals comprise:

means for filtering the data signals;

means for normalizing the data signals; and

means for binary formatting the data signals to adapt them to input specifications of the first state machines.

5. The device according to claim 4, further comprising:

means for converting the data signals using first conversion coefficients obtained a zero-calibration procedure; and

means for converting the data signals using second conversion coefficients obtained a weight-calibration procedure.

6. The device according to claim 1, wherein the main artificial proprioceptors are plantar pressure sensors, the device comprising:

means for sensing the plantar pressure at a plurality of locations, the data signals being indicative of the plantar pressure at these locations.

7. The device according to claim 6, further comprising auxiliary artificial proprioceptors, the auxiliary artificial proprioceptors including an angular position sensor provided between two movable parts of the prosthesis, the angular position sensor generating a data signal indicative of the angular position between the two movable parts, the data signal from the angular position sensor being used in at least one of the events in the second state machine.

8. The device according to claim 6, further comprising auxiliary artificial proprioceptors, the auxiliary artificial proprioceptors including two angular velocity sensors, one being provided on a shank of a non-amputee leg and the other being on a residual limb, the angular velocity sensors generating data signals indicative of the angular velocity measured at each angular velocity sensor, the data signals from the angular velocity sensors being used in at least one of the events in the second state machine.

9. The device according to claim 6, wherein the plantar pressure is sensed for at least four locations, two of the locations being at a right foot and two of the locations being at a left foot.

10. The device according to claim 7, wherein one of the locations at the right foot and one at the left foot are at a calcaneus region, another one of the locations at the right foot and one at the left foot are at a metatarsophalangeal region.

11. The device according to claim 10, wherein the right and left plantar pressure sensors are provided in corresponding insoles.

12. The device according to claim 10, wherein one of the feet is an artificial foot, the other being a natural foot.

13. The device according to claim 10, wherein both feet are artificial feet.

14. The device according to claim 10, wherein the means for obtaining the third derivative signal for at least one of the data signals comprising:

means for obtaining the third derivative for the data signal indicative of the plantar pressure at the calcaneous region of the right foot; and

means for obtaining the third derivative for the data signal indicative of the plantar pressure at the calcaneous region of the left foot.

15. The device according to claim 14, wherein further comprising:

means for calculating complementary signals from at least some of the data signals, the states of the main artificial proprioceptors being selected with data, complementary and derivative signals.

16. The device according to claim 15, wherein the means for calculating complementary signals comprising:

means for calculating a first complementary signal using the data signals indicative of the plantar pressure at the calcaneus region and at the metatarsophalangeal region of the left foot;

means for calculating a second complementary signal using the data signals indicative of the plantar pressure at the calcaneus region and at the metatarsophalangeal region of the right foot;

means for calculating a third complementary signal using the data signals indicative of the plantar pressure at the calcaneus region of the right foot and that of the left foot;

means for calculating a fourth complementary signal using the data signals indicative of the plantar pressure at the metatarsophalangeal region of the right foot and that of the left foot; and

means for calculating a fifth complementary signal using the data signals indicative of the plantar pressure at the calcaneus region of the right foot and that of the left foot, and the metatarsophalangeal region of the right foot and that of the left foot.

17. The device according to claim 1, wherein the means for generating the phase of locomotion portion using the states of the main artificial proprioceptors comprising:

means for appending binary labels representing the state of each main artificial proprioceptor to create a binary label representing the phase of locomotion portion.

18. The device according to claim 1, further comprising:

means for receiving at least some of the data signals from a wireless transmission.

19. A control system for controlling an actuated prosthesis in real time, the system comprising:

a plurality of main artificial proprioceptors;

means for obtaining a first and a second derivative signal for at least some of the data signals;

means for obtaining a third derivative signal for at least one of the data signals;

a set of first state machines, the first state machines being used to select one state among a plurality of possible states for each main artificial proprioceptor with the corresponding data and derivative signals;

means for generating the phase of locomotion portion using the states of the main artificial proprioceptors;

a second state machine, the second state machine being used to select the portion of locomotion among a plurality of possible portions of locomotion using events associated to the data signals;

means for calculating a locomotion speed value;

means for storing a lookup table comprising coefficient values with reference to at least phases of locomotion, portions of locomotion and locomotion speed values;

means for determining actual coefficient values from the lookup table using at least the phase of locomotion portion, the portion of locomotion and the locomotion speed value;

means for calculating at least one dynamic parameter value of the actuated prosthesis using the coefficient values from the lookup table and at least some of the data signals; and

means for converting the dynamic parameter value into an output signal to control the actuated prosthesis.

20. The method according to claim 19, wherein the means for storing the lookup table comprise coefficient values with reference to phases of locomotion, portions of locomotion, locomotion speed values and data signals in a binary format, the means for determining coefficient values from the lookup table using the phase of locomotion portion, the portion of locomotion, the locomotion speed value and the binary formatted data signals.

21. The system according to claim 19, wherein the actuated prosthesis is an actuated leg prosthesis for above-knee amputees, the means for calculating at least one dynamic parameter value comprising:

means for calculating at least one torque value and angular position value.

22. The system according to claim 19, wherein the actuated prosthesis includes an actuator using electric power, the output signal being indicative of the electrical power to be supplied to the actuator.

23. The system according to claim 19, further comprising:

means for adjusting the output signal in response to at least one feedback signal received from the prosthesis.

24. The system according to claim 23, wherein there are at least a first and a second feedback signal, the first feedback signal being indicative of a relative angular position measured between two movable parts of a knee joint, and the second feedback signal being indicative of a torque value measured between the two movable parts.

25. The system according to claim 19, wherein the lookup table comprises experimental data obtained using a non-amputee.

26. The system according to claim 19, further comprising:

means for pre-processing the data signals before obtaining the derivative signals.

27. The system according to claim 26, wherein the means for pre-processing comprising:

means for filtering the data signals;

means for normalizing the data signals; and

means for binary formatting the data signals to adapt them to input specifications of the first state machines.

28. The system according to claim 27, wherein the step of normalizing the data signals comprising:

means for converting the data signals using first conversion coefficients obtained during a zero-calibration procedure; and

means for converting the data signals using second conversion coefficients obtained during a weight-calibration procedure.

29. The system according to claim 19, wherein the main artificial proprioceptors include plantar pressure sensors, the system comprising:

means for sensing the plantar pressure at a plurality of locations, the data signals being indicative of the plantar pressure at these locations.

30. The system according to claim 29, wherein the plantar pressure is sensed for at least four locations, two of the locations being at a right foot and two of the locations being at a left foot.

31. The system according to claim 29, further comprising auxiliary artificial proprioceptors, the auxiliary artificial proprioceptors including an angular position sensor provided between two movable parts of the prosthesis, the angular position sensor generating a data signal indicative of the angular position between the two movable parts, the data signal from the angular position sensor being used in at least one of the events in the second state machine.

32. The system according to claim 29, further comprising auxiliary artificial proprioceptors, the auxiliary artificial proprioceptors including two angular velocity sensors, one being provided on a shank of a non-amputee leg and the other being on a residual limb, the angular velocity sensors generating data signals indicative of the angular velocity measured at each angular velocity sensor, the data signals from the angular velocity sensors being used in at least one of the events in the second state machine.

33. The system according to claim 30, wherein one of the locations at the right foot and one at the left foot are at a calcaneus region, another one of the locations at the right foot and one at the left foot are at a metatarsophalangeal region.

34. The system according to claim 31, wherein the right and left plantar pressure sensors are provided in corresponding insoles.

35. The system according to claim 31, wherein one of the feet is an artificial foot, the other being a natural foot.

36. The system according to claim 31, wherein both feet are artificial feet.

37. The system according to claim 31, wherein the means for obtaining the third derivative signal for at least one of the data signals comprising:

means for obtaining the third derivative for the data signal indicative of the plantar pressure at the metatarsophalangeal region of the right foot; and

means for obtaining the third derivative for the data signal indicative of the plantar pressure at the metatarsophalangeal region of the left foot.

38. The system according to claim 37, wherein further comprising:

means for calculating complementary signals from at least some of the data signals, the states of the main artificial proprioceptors being selected with data, complementary and derivative signals.

39. The system according to claim 38, wherein the means for calculating the complementary signals from at least some of the data signals comprising:

means for calculating a first complementary signal using the data signals indicative of the plantar pressure at the calcaneus region and at the metatarsophalangeal region of the left foot;

means for calculating a second complementary signal using the data signals indicative of the plantar pressure at the calcaneus region and at the metatarsophalangeal region of the right foot;

means for calculating a third complementary signal using the data signals indicative of the plantar pressure at the calcaneus region of the right foot and that of the left foot;

means for calculating a fourth complementary signal using the data signals indicative of the plantar pressure at the metatarsophalangeal region of the right foot and that of the left foot; and

means for calculating a fifth complementary signal using the data signals indicative of the plantar pressure at the calcaneus region of the right foot and that of the left foot, and the metatarsophalangeal region of the right foot and that of the left foot.

40. The system according to claim 19, wherein the means for generating the phase of locomotion portion using the states of the artificial proprioceptors comprising:

means for appending binary labels representing the state of each artificial proprioceptor to create a binary label representing the phase of locomotion portion.

41. The system according to claim 19, further comprising:

means for receiving at least some of the data signals from a wireless transmission.