非惯性系下舰载稳定平台动力学建模与分析

Dynamic modeling and analysis of shipborne stable platforms in non-inertial system

为解决舰船在恶劣海况下产生的大幅度、多维度的不规则摇荡运动,提出了一种6-DOF并联平台隔离舰船运动的方案,并对该方案的动力学特性进行了深入研究。首先,基于矢量关系推导该平台构件在惯性坐标下的速度、Jacobi矩阵和能量方程式,由拉格朗日方程和虚功原理得到其在非惯性系下的显式动力学方程。其次,利用Adams搭建该平台的虚拟缩比模型,采用P-M波谱和响应幅值算子模拟复杂海况下舰船的摇荡运动,基于SIMULINK软件实现MATLAB软件与Adams软件联合仿真。最后,计算分析5级海况下的运动实例,理论结果与仿真结果的驱动力误差在0.11%内,验证了本文动力学模型的正确性,且计算结果表明,平台可分别补偿船舶95.7%、97.7%和87.9%的横、纵和艏摇运动,验证了所提方案的有效性。研究结果对非惯性系下舰载稳定平台的动力学控制具有指导意义。

Here,to deal with large amplitude and multi-dimensional irregular sway motion of ships under harsh sea conditions,a 6-DOF parallel platform scheme to isolate ship motion was proposed,and dynamic characteristics of this scheme were deeply studied.Firstly,based on vector relations,velocity,Jacobi matrix,and energy equations of platform components in inertial coordinates were derived,and their explicit dynamic equations in non-inertial system were deduced using Lagrange equation and virtual work principle.Secondly,the virtual scaled model of the platform was built using the software Adams,and sway motion of ship under complex sea conditions was simulated using P-M wave spectrum and the software RAO.Joint simulation of the software MATLAB and the software Adams was realized based on the software SIMULINK.Finally,ship motion examples under level 5 sea conditions were calculated and analyzed.It was shown that the driving force error between theoretical results and simulation results is within 0.11%to verify the correctness of the dynamic model derived here;the platform can compensate ship’s roll,pitch and yaw motions by 95.7%,97.7%and 87.9%,respectively to verify the effectiveness of the proposed scheme;the study results have guiding significance for dynamic control of shipborne stable platforms in non-inertial system.