Affiliations 

  • 1 Universiti Teknologi MARA
MyJurnal

Abstract

A prototype of three-fingered robot hand was very rigid in its motion, and prone to damages when dealing with hard surfaces or when subjected to external environmental forces. The robot hand could damage fragile objects during grasping tasks if a position control alone is used. Therefore, this study proposes application of force control to the robot hand to improve its current grasping capabilities. Impedance control that considers the dynamic of the robot to produce the softness like human hand was implemented in this study. The dynamical behaviour of the robot hand strongly depends on the impedance parameters known as virtual mass, damping and stiffness. Therefore, the optimal values of impedance parameters need to be investigated to develop a position-based impedance control for the robot finger. Hence, the objective of this study is to determine the optimal value of impedance parameters to impose desired dynamics to the robot system. A constant force weighing 100 g was used by implementing varying impedance parameters to the tip-end’s position. Three experiments were conducted: first to decide the order of parameters to be adjusted, then to determine the optimal value of impedance parameters, and finally to test the optimal values with random force applied to the robot finger. The determined optimal values are: stiffness=1000, damping=10 and mass=1. Thus, the combined parameters have proven that the modified position is capable of responding according to the exerted contact force.