Carbon fiber contactor in polymer resistive position sensors

Abstract

Potentiometric position sensors are widely used in many industries. Applications in the automotive industry are most apparent and important. The position sensors are typically constructed with a polymer resistive element and a sliding electrical contactor or "wiper" that is made from various noble metals or alloys. Electrical noise and wear are often associated with such position sensors. A new concept for contactors in the position sensors has been proposed that use carbon fiber to form contact tips that result in an exceptionally large number of contact points. Preliminary tests have demonstrated improved electrical performance and durability with this system. This paper discusses the design requirements and performance characteristics of position sensors using these carbon fiber contactors.