04778175 is referenced by 20 patents and cites 12 patents.

An improved electronic control system for an exercise machine of the type having electrically actuated brakes as the resistance force for the exercise. The accuracy of the system in terms of actual resistance force delivered by the machine compared with the user-selected value is improved through techniques for compensating for hysteresis effects in the brakes. When changing the output of the brakes on each half cycle of the exercise in accordance with user-selected values, the system compensates for hysteresis effects in the brake in responding to increased current, decreased current, or steady-state current conditions. A simple but effective system is provided to let the user select "soft" limits for a particular range of motion of the exercise apparatus. The limits are in the form of an audible beep rather than a hard mechanical limit, and they are set as the system learns the desired range of motion from the user on a first cycle through the exercise.

Title
Electronic control of resistance force for exercise machine
Application Number
6/903297
Publication Number
4778175
Application Date
September 2, 1986
Publication Date
October 18, 1988
Inventor
Robert B Carlson
Bloomington
MN, US
Frederic D Wucherpfennig
Bloomington
MN, US
Agent
R Lawrence Buckley
Assignee
The Toro Company
MN, US
IPC
A63B 21/24
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