IMPEDANCE SIMULATING MOTION CONTROLLER FOR ORTHOTIC AND PROSTHETIC APPLICATIONS

• US 20150297368A1
• Filed: 05/27/2015
• Published: 10/22/2015
• Est. Priority Date: 05/03/2011
• Status: Active Grant

• Current Assignee: Ossur hf
• Original Assignee: Ossur hf
• Inventors: Langlois, David
• Granted Patent: US 10,251,762 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61F 2/60 Artificial legs or feet or parts thereof
• CPC Class Codes: A61F 2/70 electrical
• CPC Class Codes: A61F 2002/5038 Hinged joint, e.g. with transverse axle restricting the movement for implantable joints A61F2002/30624
• 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 2002/7615 Measuring means for implanting artificial joints A61F2/4657
• CPC Class Codes: A61F 2002/7625 for measuring angular position
• CPC Class Codes: A61F 2002/7635 for measuring force, pressure or mechanical tension
• CPC Class Codes: A61F 2002/764 for measuring acceleration
• CPC Class Codes: A61F 5/0102 specially adapted for correcting deformities of the limbs or for supporting them; Ortheses, e.g. with articulations
• CPC Class Codes: G05B 15/02 electric

Abstract

An impedance simulating motion controller for orthotic and prosthetic devices includes an equilibrium trajectory generator that receives locomotion data regarding the locomotion of a user, a dynamic trajectory compensator that generates one or more control parameters based on the locomotion data and one or more physiological characteristics of the user, and a dynamic gain tuner that adjusts the one or more control parameters based on a gain scaling factor that is calculated using a measured deflection point and an expected deflection point. The adjusted control parameters are used to control movement of an actuator of an orthotic or prosthetic device.

Claims

1-31. -31. (canceled)

32. A motorized prosthetic orthotic device (POD) provided with a joint comprising:

a sensor configured to measure a joint angle of the joint of the motorized POD during a gait cycle; and

a controller configured to;

determine one or more control signals that control a stiffness of one or more actuators of the motorized POD based at least in part on a difference of the measured joint angle from an equilibrium joint angle during stance phase of the gait cycle, wherein the equilibrium joint angle is approximately constant during at least a majority of the stance phase, and

cause the one or more control signals to be communicated to the one or more actuators to control the stiffness of the one or more actuators.

33. The POD of claim 32, wherein the equilibrium joint angle is determined using a regression line of torque-angle during stance phase of a gait cycle.

34. The POD of claim 32, wherein the stiffness of the one or more actuators causes the measured joint angle to approximate a kinematic reference model during the stance phase.

35. The POD of claim 32, wherein the one or more control signals are based at least in part on at least a position set-point, a proportional gain, and a derivative gain.

36. The POD of claim 32, wherein the one or more control signals are based at least in part on one or more control parameters that are generated based at least in part on general characteristics of human locomotion using non-complex mathematical relationships.

37. The POD of claim 32, wherein the equilibrium joint angle during the stance phase is different from an expected joint angle during the stance phase.

38. The POD of claim 32, wherein the one or more control signals are determined based at least in part on at least one of body mass or weight.

39. The POD of claim 32, wherein the one or more control signals are updated between gait cycles during movement of a user.

40. The POD of claim 32, wherein the measured joint angle is a maximum joint angle during the stance phase.

41. The POD of claim 32, wherein the equilibrium joint angle changes during the stance phase.

42. The POD of claim 32, further comprising a dynamic gain tuner configured to alter the one or more control signals upon determining that a difference between at least one of the measured joint angle and an expected joint angle or the measured joint angle and the equilibrium joint angle satisfies a threshold tolerance level.

43. The POD of claim 42, wherein the dynamic gain tuner is further configured to update the gain scaling factor between gait cycles during movement of a user.

44. A non-transitory computer-readable medium comprising executable instructions that when executed by one or more processors cause the one or more processors to:

determine a joint angle of a joint of a motorized POD during a gait cycle;

determine one or more control signals that control a stiffness of one or more actuators of the motorized POD based at least in part on a difference of the determined joint angle from an equilibrium joint angle during stance phase of the gait cycle, wherein the equilibrium joint angle is approximately constant during at least a majority of the stance phase; and

cause the one or more control signals to be communicated to the one or more actuators to control the stiffness of the one or more actuators.

45. The non-transitory computer-readable medium of claim 44, wherein the equilibrium joint angle is determined using a regression line of torque-angle during stance phase of a gait cycle.

46. The non-transitory computer-readable medium of claim 44, wherein the one or more control signals are based at least in part on at least a position set-point, a proportional gain, and a derivative gain.

47. The non-transitory computer-readable medium of claim 44, wherein the one or more control signals are determined based at least in part on at least one of body mass or weight.

48. The non-transitory computer-readable medium of claim 44, wherein the one or more control signals are updated between gait cycles during movement of a user.

49. A method of controlling a motorized prosthetic orthotic device (POD) provided with a joint comprising:

measuring a joint angle of a joint of the motorized POD during a gait cycle;

determining one or more control signals that control a force of one or more actuators of the motorized POD based at least in part on a difference of the measured joint angle from an equilibrium joint angle during stance phase of the gait cycle, wherein the equilibrium joint angle is approximately constant during at least a majority of the stance phase; and

causing the one or more control signals to be communicated to the one or more actuators to control the force of the one or more actuators.

50. The method of claim 49, wherein the force of the one or more actuators causes the measured joint angle to approximate a kinematic reference model during the stance phase.

51. The method of claim 49, wherein the one or more control signals cause the force of the one or more actuators to increase based at least in part on an increase in the difference of the measured joint angle from the equilibrium joint angle.