Kinematics and mode selection for separation motion of AUV

Two modes of load separation from the head of AUV (autonomous underwater vehicle) are researched. Based on the given dynamic equations, a set of transform models of the beginning position and the beginning attack angle of the separated load arc deduced firstly. The results of the subsequent simulation show that the first mode for the load separated from the AUV by an impulse force is complicated and unsafe because the load always has a rise motion whose amplitude is much related to the velocity of AUV and the separating force and because at the same time the rise motion is always accompanied with an unsuitable pitch attitude which increases quickly within a short time. Simulation results also show that the second mode, in which the load turns around an axis in the bottom of the head of the AUV by a set angle of 90 degrees with the gravitation of load itself firstly and then makes a thorough separation from the AUV, is desirable because the load has no rise motion and has more appropriate pitch attitude, thus reducing the chance for the separated load to knock against the AUV.