06113642 is referenced by 111 patents and cites 15 patents.

A computer controlled hydraulic resistance device for apparatus such as a prosthetic knee for above knee amputees, includes a two stage pilot operated solenoid 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 by a spring biased magnet and a magnetically actuated electronic sensor 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 has magnetically actuated electronic sensors which sense positions of the apparatus and feed back to the micro-controller for applying a predetermined resistance profile to the apparatus.

Title
Computer controlled hydraulic resistance device for a prosthesis and other apparatus
Application Number
883614
Publication Number
6113642
Application Date
November 10, 1998
Publication Date
September 5, 2000
Inventor
William G Gruesbeck
Beavercreek
OH, US
Steven H Petrofsky
Dayton
OH, US
Agent
Jacox Meckstroth & Jenkins
Assignee
Mauch
OH, US
IPC
F16F 9/512
A61F 2/70
A61F 2/64
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