A sensorless approach for cable failure detection and identification in cable-driven parallel robots

Cable-driven parallel robots (CDPRs) are a particular class of parallel robots that provide several advantages that may well be received in the industrial field. However, the risk of damage due to cable failure is not negligible, thus procedures that move the end-effector to a safe pose after failure are required. This work aims to provide a sensorless failure detection and identification strategy to properly recognize the cable failure event without adding additional devices. This approach is paired with an end-effector recovery strategy to move the end-effector towards a safe position, thus providing for a complete cable failure recovery strategy, which detects the failure event and controls the end-effector accordingly. The proposed strategy is tested on a cable-driven suspended parallel robot prototype composed of industrial-grade components. The experimental results show the feasibility of the proposed approach.