Development of a force sensor working with MR elastomers

This paper presents the development of a new force sensor with MR elastomer as a sensing element. One key element in this study was to find a suitable material with high sensing capabilities which can be used for developing a sensor. Thus different MR elastomers, with ingredients of carbonyl iron particle, graphite, silicone oil and silicone rubber, were manufactured and measured with a modified rheometer. The effects of additives on the sensing capabilities were systematically investigated and an optimal MR elastomer sample was selected for design and manufacturing of a force sensor prototype. The development sensor prototype consists of three units: mechanical unit, electrical circuit and LED display unit. The mechanical unit includes the MRE sample and the interface to the electronic circuit. A signal conditioning circuit was developed for calibrating output voltages, which are displayed on a LCD panel. The components of the electronic part were soldered on a board and communicate with the mechanical part for signal detection and testing. Overall the developed new MR elastometer based force sensor is able to detect external forces at the selected force ranges.