Modelling and designing controller of two different mechanical coupled motors for enhancement of underwater vehicles performance

This study presents a new design for mechanical coupling of two different motors which enables to share the load between the two motors with a proposed ratio without using flexible connector and with no expected oscillations. This enhances the buoyant cruising speed compared with the best common twin-armature motor without increasing the weight and volume of the drive system. However, this design requires a complicated control system because of the different characteristics of the motors. A controller is recommended and its stability is verified. To convert the control system into two simple controls, slow and fast dynamics are segregated. In this way, a non-linear multi-input/multi-output system with disturbance is splitted into two single-input/output sub-systems; therefore controller can be designed easier. The simulation results for two different conventional and fuzzy controllers are presented. The experimental results on the prototype system confirm the simulation results.