Online health monitoring of robotic joint motor-drive systems is of paramount importance for robots utilized in remote, safety-critical, and hazardous environments. Joint motors and the associated power electronic drives are prone to hardware failures in harsh environments and may yield joint failures. In this paper, a robust fault diagnosis technique of semiconductor switches is proposed for brushless DC (BLDC) motor drive systems in robotic applications based on the stator current signature analysis. The performance of the BLDC joint motors is investigated under inverter switches' open-circuit faults using finite element (FE) co-simulation tools. Finally, theoretical findings are validated using the Kinova Gen3 robot arm to highlight the effect of joint faults on the robot’s reachability of desired task locations.
