Embedded Joint Torque Sensor with Reduced Torque Ripple of Harmonic Drive
Joint torque sensors are widely used in service robots for force control and collision detection. However, since torque sensors are often directly connected to a harmonic drive, it must be insensitive to torque ripple, the noise from the harmonic drive due to its unique structure. The magnitude of torque ripple is several times higher than electrical noise, and it significantly decreases robot’s force control and collision detection performances. In this study, we propose the torque ripple reduction method through the change of the installation position of Wheatstone bridges, and the structure design of torque sensor for service robot arms through FEM analysis. The performance of the proposed reduction method was verified through experiments.
Keywordsjoint torque sensor torque ripple harmonic drive service robot arm
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