A goniometric sensor (1) for measuring the relative rotation of two objects (20,25) comprising a flexible elongated element (2) whose respective ends are connected to the two objects (20, 25) and during whose bending the length variation ΔL is determined of one of the lines (15) not located at the neutral...http://www.google.de/patents/US7373721?utm_source=gb-gplus-sharePatent US7373721 - Goniometric sensor
