Design and validation of a robotic subsea winch with minimal sensor feedback

Teledyne SeaBotix is developing a robotic subsea winch to be used in deep deployments of an observation class (20kg) ROV to 4000 m depths. The subsea winch system can be incorporated in a self-contained launch and recovery system or via larger vehicles like work class ROVs or submarines. High reliability is an underlying design objective in subsea systems due to the very high cost of downtime or system failure. These objectives translate into a design criteria to minimize potential system failure points including: connectors, cables, and housings. Particularly of concern are connectors that have a high risk of being misused, damaged, or worn-out causing catastrophic failures. Advancements in sensor technology and related monitoring algorithms can be used to reduce if not eliminate the need of electromechanical sensors for feedback. This paper discusses a system design which incorporates novel sensing techniques to remove numerous sensors on the subsea winch while maintaining the same performance as if they were still there. The system benefits from size reduction, cost reduction and an increase in reliability, while maintaining equal performance.