Development of Interference Eliminating Circuit Embedded Multi-component Sensor

Abstract

Multi-component force sensors often encounter to undesirable interference between force and moment components due to design limitation and manufacturing capabilities. Although iterative design can reduce interference, it is difficult to eliminate completely, and conventional commercial sensors generally allow about 5% interference. In certain applications, sensors exceeding this limit are still used, with numerical post-processing of measurement data employed to eliminate interference. This approach, however, provides only intermittent results with sacrificing real-time continuity. In this study, we propose and demonstrate a novel interference-elimination system that processes the real-time output signals of Wheatstone bridge for each component forces through an eliminating circuit consisting of multiplying, summing, and amplifying processors. By directly implementing the linear equations of sensor performances, the system enables real-time elimination of interference without numeric calculation. This method improves accuracy without iterative design of sensor accommodate within limited space provided in a slender underwater models. The developed approach is experimentally validated through calibration tests, showing effectiveness in elimination of dominant interference and improving the measurement precision. The results confirm that the proposed analog circuit is an efficient and practices for real-time force/moment measurement in experiments.