Human-Robot Collaboration in a Sanding Task

Robots can help reduce physical stress in manual sanding, but implementation has been challenging due to the skill required, task variability, and robot limitations. In shared control (SC) a robot operates semi-autonomously while the human provides real-time corrections. A laboratory study tested the effectiveness of SC for removing paint using an orbital sander. A robot autonomously sanded the surface, and twenty participants sanded manually and in collaboration with a robot using SC. Subjective discomfort for manual sanding was greater than SC in the upper arm by 28.5%, the lower arm by 29%, the hand by 38%, and the shoulder by 42%. Muscle fatigue, measured using EMG, was 22.4% greater for the manual condition. Cognitive workload measured using the NASA TLX was 14.25% more for manual sanding. Digital imaging showed that SC outperformed the fully autonomous robot by 10.75% for uniformity, by 4.96% for quantity, and by 6.06% for average performance.