Analysis and Test of an Optimal Propeller Speed Schedule to Reduce AUV Energy Consumption

Methods are sought to extend the range and endurance of Autonomous Underwater Vehicles (AUVs) by reducing their energy consumption. This paper documents an effort to develop and implement a propeller speed command function that is scheduled relative to the measured along-track water current. The advantage of the propeller scheduling approach is that it does not require modification of the vehicle configuration. A theoretical analysis shows that the optimal propeller speed schedule reduces energy consumption by up to ten percent in relatively high water current environments. Field test results confirm this benefit.