Vibration analysis of the rudder drive system of an underwater glider

Underwater gliders are widely used for the ocean environment exploration. This paper analyses the vibration characteristics of the rudder drive system of an underwater glider. The meshing frequencies of the gearbox in the rudder drive system are calculated. The excitation characteristics of the actuator in the rudder drive system are tested by an experiment study. A finite element model of the rudder drive system for dry and wet modal conditions is developed. The mode frequencies and mode shapes of rudder drive system in the air and water are calculated by using the finite element software. The results show that the medium affects the modal frequencies of system. Comparing the results of simulation and experiment, it concludes that main excitation frequencies are different from the mode frequencies. The rudder drive system has no resonance when the actuator is working. The structure design is reasonable one in the studied frequency range.