US Patent 8,251,938
United States Patent and Trademark Office
University of Iowa Research Foundation (Iowa City, IA, US)
A device may include a first plate and a second plate, and a linkage system that attaches the first plate and the second plate to one another such that the plates are capable of translating relative to each other, and the plates are incapable of rotating relative to each other.
Morcuende, Jose; Grosland, Nicole M.; Jensen, Kelly; Jensen, Nicole; and Kruse, Robert Providing relative translation without rotation. US Patent 8,251,938 filed April 30, 2009 and issued August 28, 2012. https://ir.uiowa.edu/patents/580