Design of a Hollow Hexaform Torque Sensor for Robot Joints

This work describes the design of a new one-axis torque sensor. It achieves the conflicting requirements of high stiffness for all six force and torque components, high sensitivity for the one driving torque of interest, and yet very low sensitivity for the other five force/torque components. These properties, combined with its donut shape and small size, make this sensor an ideal choice for direct-drive robotic applications. Experimental data validate the basic design ideas underlying the sensor’s geometry, the finite element model used in its optimization, and the advertised performance. KEY WORDS—torque sensor, robot joint, joint torque control