Longitudinal sliding mode control of a new type long distance autonomous underwater vehicle (auv)

A new type long distance experimental AUV, as shown in Fig. 1, has been designed and constructed in Northwestern Polytechnical University. This new type AUV has multiple manipulators and not only can cruise as the traditional AUV by the control surfaces and the propeller, but also can hover in the water as the helicopter in air by the bow vertical cross-body thruster, stern vertical cross-body thruster, bow lateral cross-body thruster and stern lateral cross-body thruster. In the full paper, we explain in detail the design of longitudinal sliding mode control for the above-mentioned new type AUV for slow speed cruise mode, high speed cruise mode as well as hover mode. In the abstract, we just mention six important points in our design: (A)the nonlinear longitudinal kinematical equations of AUV are given as eqs. (1) through (4); (B) the linearized longitudinal kinematical equations of AUV are given as eqs. (5) through (10); (C) the equations for the sliding mode controller design are given as eqs. (11) through (26); (D) the equations for designing the slow speed cruise sliding mode controller by the control surfaces are given as eqs. (27) and (28); (E) the equations for designing the high speed cruise sliding mode controller by the control surfaces are given as eqs. (29) and (30); (F) the equations for designing the hover sliding mode controller by the bow vertical cross-body thruster and the stern vertical cross-body thruster are given as eqs. (31) and (32). The simulation results of sliding mode controller for all modes, summarized in Fig. 2 in the full paper, show preliminarily that the sliding-model controller can be adapted to all three Modes-low-speed cruise, high-speed cruise, and hover-and is robust to parameter uncertainties and unmodeled dynamics.