Method and apparatus for mimicking human gait with prosthetic knee devices and detecting when stumble recovery is needed
View Patent ↗The present invention relates to a prosthetic device including a prosthetic joint which accurately transitions between a loose mode and a stiff mode to more accurately mimic a human gait. The prosthetic joint includes a state controller which utilizes a sensor to detect prosthetic joint movement data, and compares it with prosthetic joint movement decision values to determine when a solenoid should be energized to place the prosthetic joint in the loose mode. An optimization unit connects to the prosthetic joint in a prosthetic joint system. The optimization unit generates a plurality of data files containing prosthetic joint movement data corresponding to an amputee walking without stumbling. By iteratively analyzing the prosthetic joint movement data, the optimization unit adjusts the prosthetic joint movement decision values to ensure that the prosthetic joint does not prematurely enter a stumble recovery state.
1. A prosthetic joint system capable of selectively entering a stumble recovery state, the prosthetic joint system comprising:
a prosthetic joint; and
a state controller coupled to the prosthetic joint and programmed to:
detect prosthetic joint movement data;
determine a state of the prosthetic joint using the prosthetic joint movement data; and
analyze prosthetic joint movement data detected during an un-weighted state of a prosthetic foot connected to the prosthetic joint and at least one prosthetic joint movement decision value to determine when the state of the prosthetic joint should enter a stumble recovery state.
2. The prosthetic joint system of claim 1 wherein the prosthetic joint movement data detected during the un-weighted state of the prosthetic foot includes swing time data, moment data, knee angle data, or knee angle rate of change data.
3. The prosthetic joint system of claim 1 wherein the at least one prosthetic joint movement decision value includes a maximum leg swing time.
4. The prosthetic joint system of claim 1 wherein the at least one prosthetic joint movement decision value includes a maximum knee angle or a maximum knee angle rate of change.
5. The prosthetic joint system of claim 1 wherein the at least one prosthetic joint movement decision value includes a bent knee time decision value.
6. The prosthetic joint system of claim 1 wherein the at least one prosthetic joint movement decision value includes a moment boundary value and a decreased moment time decision value.
7. The prosthetic joint system of claim 1 wherein the at least one prosthetic joint movement decision value includes a bent knee angle decision value.
8. A method for controlling when a prosthetic joint enters a stumble recovery state, the method comprising:
detecting, using a state controller, prosthetic joint movement data;
determining, using the state controller, a state of the prosthetic joint using the prosthetic joint movement data;
retrieving, using the state controller, at least one prosthetic joint movement decision value; and
analyzing, using the state controller, prosthetic joint movement data detected during an un-weighted state of a prosthetic foot connected to the prosthetic joint and the at least one prosthetic joint movement decision value to determine when the state of the prosthetic joint should enter a stumble recovery state.
9. The method of claim 8 wherein the prosthetic joint movement data detected during the un-weighted state of the prosthetic foot includes swing time data, moment data, knee angle data, or knee angle rate of change data.
10. The method of claim 8 wherein the at least one prosthetic joint movement decision value includes a maximum knee angle or a maximum knee angle rate of change.
11. The method of claim 8 wherein the at least one prosthetic joint movement decision value includes a maximum leg swing time.
12. The method of claim 8 wherein the at least one prosthetic joint movement decision value includes a bent knee time decision value.
13. The method of claim 8 wherein the at least one prosthetic joint movement decision value includes a moment boundary value and a decreased moment time decision value.
14. The method of claim 8 wherein the at least one prosthetic joint movement decision value includes a bent knee angle decision value.