Fuzzy self-organising control of a remotely operated submersible

The Marconi Minnow MK2 mine counter measures vehicle is a small tethered remotely operated vehicle (ROV) designed to investigate and prosecute objects detected via own ship sonar. Power is provided from the surface via an umbilical cable which also relays control signals and sensor data to and from the surface where the operator is stationed. The vehicle is propelled and manoeuvred by four thrusters, and designed to be slightly positively buoyant to ease recovery should the umbilical separate. The shape of ROVs has,to data, been far from streamlined. The hydrodynamic characteristics are as a result, highly nonlinear and uncertain. Techniques based on fuzzy logic can cope with nonlinearities directly, and have proven qualities of robustness that make them a natural choice for the application in question. The paper describes the design of a fuzzy self-organising autopilot for heading control of an ROV