Design and motion control of a cable-driven dexterous robotic arm

Robots with hyper degrees of freedom motion are highly flexible, hence they are the ideal candidates to work in highly-confined spaces. These dexterous robotic arms are classified into two categories, i.e., discrete and continuum. As the weight of the discrete robots is a major concern, this paper discusses about the possibility of reducing their weight by replacing the heavy actuators with light cables. The proposed cable-driven robot consists of a series of identical parallel-structured modules connected to one another via universal joints. Experimental results showed that the cables have demonstrated a good step response with no steady-state errors and a fast settling time of 0.042 seconds. By using the kinematics formulations analysed in this paper, position control has been successfully implemented on a two-module cable-driven prototype. This allows the robot to be controlled in a co-ordinated manner while maintaining a smooth trajectory.