A novel application of planar-type meander sensors

Abstract

Purpose - The purpose of this paper is to test the measurement performances of a planar-type meander sensor installed in robot foot in order to examine its potential application as ground reaction force sensor. Design/methodology/ approach - A planar-type meander sensor is composed of two pairs of meander coils. Variation of input inductance between coils serves as a measure of small displacements in a plane. Pairs of meander coils are installed in an actuated robot foot to measure displacements proportional to normal or tangential components of ground reaction force which acts upon the foot. The sensor was modeled by the concept of partial inductance and a new simulation tool was developed based on this concept. Findings - Pairs of meander coils were tested against angular displacements, and results showed that the sensor gives correct information about displacement regardless how the foot touches the ground with its whole area. Deviations between position of computed and real acting point of ground reaction force are relatively small. Owing to good results obtained, a miniaturized sensor was developed having the same performances as previously developed prototype. Originality/value - This paper presents initial work in implementing a planar-type meander sensor in robot foot as to measure ground reaction force. Developed simulation tool gives accurate analysis of inductance variation of meander structures. In addition, the measurement error and sensor's nonlinearity are analyzed. Calculated results show a good agreement with experimental results. Hence, miniaturized sensor, easier for implementation, is proposed. © Emerald Group Publishing Limited.