Calculation of deformation of a flexible contact sensor

This paper describes the calculation of deformation of a flexible contact sensor. Approximate expressions to calculate the deformation of a flexible sensor are derived using Castigliano´s theorem. Deformation of the flexible sensor is calculated in real-time with the use of measured contact forces. Measurement accuracy is confirmed experimentally. The experimental results show that the calculated deformation agrees approximately with the actual deformation. With the aim of applying this calculated deformation to certain robot tasks, the flexible sensor is attached to a robot hand, and the mechanical impedance parameters of a grasped object are estimated with the use of a Kalman filter. This grasping experiment demonstrates that these parameters are estimated exactly.