Cobot with prismatic compliant joint intended for doppler sonography

Abstract

This paper deals with a collaborative robot, i.e., cobot, coupled with a new prismatic compliant joint (PCJ) at its end-effector. The proposed collaborative solution is intended for Doppler sonography to prevent musculoskeletal disorders issues. On one hand, the Doppler sonographer's postures are investigated based on motion capture use during the arteries examination. This study highlighted that configurations adopted by angiologists lead to the musculoskeletal disorder. On the other hand, the proposed PCJ with variable stiffness gives an intrinsic compliance to the cobot handling the probe. This feature allows preserving the human safety when both human and cobot share a common workspace. The effectiveness of the proposed solution is experimentally validated through a 7-DoF Franka Emika robot virtually coupled with the PCJ, during the execution of a trajectory performed during a Doppler ultrasound exam. The impact force criterion is considered as a safety performance.