Design and Characterization of a 1-axis Compact Torque Sensor for a Collaborative Robot Arm

Abstract

The paper proposes a compact torque sensor with a support structure to minimize crosstalk which can be used in a collaborative robot arm. In the torque sensor, the torque is measured by sensing the deformation of an elastic body using strain gauges. The deformable body design was carried out by an iterative process of design modifications and FEA (Finite Element Analysis) to come up with a design which satisfied all the design requirements. Further design modifications and FEA was carried out to identify and finalize the strain gauge mounting locations on the deformable body. The signal from the strain gauges are amplified, processed and then transmitted to the robot controller using serial communication. The support structure for the torque sensor includes a bearing which minimizes the crosstalk applied on the torque sensor increasing the sensor accuracy. Experiments were carried out to characterize the torque sensor for static torque conditions and to identify the linearity of the proposed sensor. The results of the simulation analysis and experiment results suggest the effectiveness of the proposed torqued sensor.