Proposal of a tactile feedback model with reaching motion based on nonlinear dynamics of the mechanoreceptors and finger-tip-consideration of a task space P-SD Servo controller

This paper, based on the skin-sensor dynamics model [20] and the anatomical insights, we develop a candidate of the tactile feedback controller for the arm reaching tasks. In the controller, the signal from the FA1(SA1) receptors as the velocity sensors is used for the tactile feedback like task-space P-SD Servo. The velocity of the fingertip seems to be affected by the skin and receptor dynamics. Then the sensor output of the task space velocity signal becomes sensitive in the low-load region. Especially, if the sensor is in the high-load region, the sensor output will be kept but the resolution become low and is able to avoid overload output. This paper focused on the finger-tip dynamics that consists of the tissue and the cutaneous mechanoreceptors called FA1(SA1), and investigate how they affect the control strategy of the tracing motion. In the experiments, we analyzed the nonlinear biomechanical properties of the cutaneous surface and showed that the subcutaneous mechanoreceptors affect human control skill learning. In these experiments, the validity of our hypothesis was investigated.