Mechanism Analysis And Control Theory Investigation On Ship-based Stabilizing Platform With Foldable Parallel Mechanism

With the effect of the ocean, ships have multi-DOF-periodic motion which badly influences the daily life and work of sailors, equipment safety, accuracy of weapon launching and taking off and landing of carrier aircrafts. Stabilizing of platform as a ship’s partial anti-rolling equipment, is used to isolate the ship’s movement and offer a comparatively stable situation for the staff and facilities and is widely applied in carrier arming. It is of great significance for the development of national economy and security. In order to deal with that series turntable is difficult to achieve multidimensional stability and load-carrier capacity this paper aims at the mechanism and control theory of the ship-based stabilizing platform with parallel structure. The mean research contents are as follows:(1) Analyze the property of the sea wave based on Longuet-Hinggins model and simulate the movements of the sea wave. Study the force of the ship using the Newton-Euler equation. The movements of the ship are investitaged based on Conolly theory. According to the autoregression model of time-series, build a predicted model of ship’s motion and make a simulational analysis of the model. On the basis of the work above and considering the practical application, choose the parallel 6-RUS foldable mechanism as the ship-based stabilizing platform.(2) Apply screw theory into the motion description of the rigid body and combining with the adjoint transformation of the screw the relationship between the motion screw in inertia system and in non-inertial system is analyzed. Build the kinematics model of parallel ship-based stabilizing platform in non-inertial frame including inverse displacement analysis, forward displacement analysis, velocity analysis and acceleration analysis.(3) The equation have the property of coordinate-invariant. Using this property of the eqution to build the dynamic model of the ship-based stabilizing platform and analyze the physical meaning of every part in the dynamic model.(4) The computed-moment controller which has feed-forward compensation of transport inertial force and coriolis inertial force is designed in workspace of the stabilizing platform. Active Disturbances Rejection computed-moment Controller is applied. Using Extended State Observer(ESO) to estimate the total uncertainty of the system and compensate the disturbing moment in real time. A contrast analysis is made between the two controller mentioned in this chapter through Adams and Matlab co-simulation.(5) The sliding triode variable structure controller which has feed-forward compensation of transport inertial force and coriolis inertial force is designed in workspace of the stabilizing platform. Active Disturbances Rejection sliding triode variable structure Controller is applied. Using Extended State Observer(ESO) to estimate the total uncertainty of the system and compensate the disturbing moment in real time. A contrast analysis is made between the two controller mentioned in this chapter through Adams and Matlab co-simulation.