Research and Experiment on Viscous Friction Power Loss of Deep-sea Electric Manipulator

Deep-sea electric manipulator usually adopts internally oil-filled method, and the joint motors are soaked in the oil, so that the oil pressure and the water pressure outside will be basically balanced. However, due to the high pressure in deep sea, the oil viscosity increases, and the viscous frictional resistance will cause the viscous power loss of motor to become bigger. This paper establishes the theoretical model of viscous friction power loss and measures the viscous friction power loss of pitching joint motor and wrist-clamp module in oil-filled movement under the simulated pressure at different depths through pressure experiment. Meanwhile, the model parameter of viscous power loss is obtained by data fitting. Through the established model of viscous power loss, we can predict the viscous friction power loss of electric manipulator when it operates under water. At the same time, this model provides theoretical basis for dynamics modeling of deep-sea electric manipulator and trajectory optimization based on energy consumption.