ΣVII is mobile by means of six thrusters. Fore and aft, or surge movement is controlled by two brushed VideoRay thrusters. Vertical heave is controlled by three Seabotix thrusters mounted in the upper center of the ROV, and horizontal sway, as well as yaw is achieved through one Seabotix thruster mounted within the lower center portion of the frame. The company wanted to build their own thrusters but time constraints did not allow such a project. The VideoRay thrusters have over a 2-1 thrust to weight ratio, and give ΣVII smooth, fast movement underwater. Their motor controllers are tuned for fast response, so there is no delay between deck side signal and movement of the machine. The Seabotix thrusters are produced specifically for ROV’s. Each produces 2.2 Kg of thrust, and are equipped with a brushed motor housing, end caps, propellers and kort nozzles. All of the thrusters are interfaced into the frame using mounting bars for easy removal and maintenance.
Propulsion
