File:Passive programmable resistance device.png

Summary

File information
Description	A passive programmable resistance device uses a closed loop feedback for controlling resistance to rotational or translational motion of an object. One or more actual parameters, such as force or position, are measured and compared with desired parameters. The differences are used to provide a control signal which controls the resistance to the movement of the object.
Source	US Patent #4,354,676
Date	1978-10-13
Author	Gideon B. Ariel (PepsiCo Inc)
Permission (Reusing this file)	This image is from US patent #4,354,676[1] with a priority date of October 13, 1978. It was published without a copyright notice and a search finds no subsequent registration. It is therefore in the public domain.

Licensing

This image is in the public domain in the United States because it was first published in the U.S. between 1978 and March 1, 1989, and a substantial number of authorized copies were distributed to the public without a copyright notice, and where the copyright was not later registered with the US Copyright Office.

Outside the US, explicit copyright notices were not necessarily required, other jurisdictions having other rules, and so this image might not be in the public domain outside the United States. See Wikipedia:Public domain and Wikipedia:Copyrights for more details.

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