Computer controlled hydraulic resistance device for a prosthesis and other apparatus
First Claim
1. A device for producing a controlled variable resistance to apparatus including a first member moveable relative to a second member, said device comprising means including a hydraulic actuator for connecting said first member to said second member, said actuator including a housing enclosing a moveable resistance applying member separating a first chamber and a second chamber within said housing, a hydraulic fluid within said chambers, means defining hydraulic fluid passages connected to said chambers, a solenoid controlled valve connected to control the flow of hydraulic fluid through said passages, means for independently sensing the hydraulic fluid pressure within each of said first and second chambers, and a computer control system responsive to said pressure sensing means for actuating said valve to control precisely the flow of said fluid through said valve and into and out of said first and second chambers and to compensate for variations in said device and in said fluid viscosity.
4 Assignments
0 Petitions
Accused Products
Abstract
A computer controlled hydraulic resistance device for apparatus such as a prosthetic knee for above knee amputees, includes a solenoid actuated valve connected to control the flow of hydraulic fluid to and from a hydraulic actuator which applies resistance to the prosthetic knee or other apparatus through a coupling. Hydraulic pressure is sensed on the high and low side of the actuator and is used by a micro-controller in a closed-loop manner to compensate automatically for variations in the device and in the hydraulic fluid viscosity. The device also senses the position of the apparatus and feedsback to the micro-controller for applying a predetermined resistance profile to the apparatus.
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Citations
16 Claims
- 1. A device for producing a controlled variable resistance to apparatus including a first member moveable relative to a second member, said device comprising means including a hydraulic actuator for connecting said first member to said second member, said actuator including a housing enclosing a moveable resistance applying member separating a first chamber and a second chamber within said housing, a hydraulic fluid within said chambers, means defining hydraulic fluid passages connected to said chambers, a solenoid controlled valve connected to control the flow of hydraulic fluid through said passages, means for independently sensing the hydraulic fluid pressure within each of said first and second chambers, and a computer control system responsive to said pressure sensing means for actuating said valve to control precisely the flow of said fluid through said valve and into and out of said first and second chambers and to compensate for variations in said device and in said fluid viscosity.
- 10. A device for producing a controlled variable resistance for a prosthesis including a first member pivotally connected to a second member, said device comprising means including a rotary hydraulic actuator for connecting said first member to said second member, said actuator including a housing enclosing a resistance applying vane type rotor separating a first chamber and a second chamber within said housing, a hydraulic fluid within said chambers, means defining hydraulic fluid passages connected to said chambers, a solenoid controlled valve connected to control the flow of hydraulic fluid through said passages, means for independently sensing the hydraulic fluid pressure within each of said first and second chambers on opposite sides of said rotor, and a computer control system responsive to said pressure sensing means for actuating said valve to control precisely the flow of said fluid through said valve and into and out of said first and second chambers and to compensate for variations in said device and in said fluid viscosity.
Specification