Analysis of Tactile Slippage Control Algorithm for Robotic Hand Performing Grasp-Move-Twist Motions

This paper presents an analysis result of grasp-move-and-twist motions of robotic hands equipped with optical three-axis tactile sensor to evaluate performance of a new control algorithm based on tactile slippage sensation. The optical three-axis tactile sensor is capable of defining normal and shear forces simultaneously. The proposed algorithm consists of robot arm and hand controls based on parameters of normal and shear force, and slippage detection. To improve performance during grasp, move and twist motions, we present analysis of slippage direction and classify the control algorithm in two phases: grasp-move-release and grasp-twist. We present detailed explanation of the control algorithm based on the existing robot arm control system. The experiment is conducted using a bottle cap, and the analysis results show that the slippage control parameters enhanced performance of grasp control in simultaneous robot tasks. Experimental results revealed good performance of the proposed control algorithm to accomplish the proposed grasp-move-and-twist motions.