When a propulsion system is driven by the cardan joint，shaft angle and pedestal angle will be produced in the propulsion system due to the structural features，the limited structure space and the assembly accuracy of cardan joint，which will cause additional load，vibration and noise during operation. The additional load on the connecting parts will cause the forced vibration of the component. In view of this，the characteristics of the driving shaft are analyzed by MATLAB simulation when shaft angle and pedestal angle exist. Vibration sound radiation of the underwater vehicle under different shaft angles and pedestal installation angles is tested. Test result shows that shaft angles affect system’s vibration sound radiation，which has certain instructive significance to the design，installation and debugging of the same type of products[1].
