Measurement crosstalk elimination of torque encoder using selectively compliant suspension

Abstract

Realization of rigid and sensitive torque sensor is one of the key factors for the success of robots. With the conventional detectors as strain gauges, poor S/N (signal to noise) ratio has been the limitation of torque sensor sensitivity. Torque Encoder uses a linear encoder as a detector and significantly enhanced the S/N ratio, and realized stiff and sensitive torque sensor. However, the crosstalk in torque measurement was still an open problem as in other sensing methods. In this paper, we analyzed the cause of the crosstalk and proposed the mechanism to suppress the crosstalk using selectively compliant suspension mechanism. Design methodology, implementation to minimize crosstalk with minimal sensitivity loss are presented. Evaluation on a prototype of the mechanism is carried out to show the effectiveness of the mechanism.