基于性能驱动的船载稳定平台尺度参数优化设计

为提升船载稳定平台的运动学性能，针对■并联机构的尺度参数优化问题，以机构的工作空间体积和全域力传递率为综合评价指标，采用小生境遗传算法优化得到稳定平台的最佳几何构形。具体地，采用数值法与解析法相结合的方式判断支链长度、关节转角、奇异位形等约束条件的生效情况，求解出并联稳定平台的工作空间；基于力雅可比矩阵逆矩阵的最小奇异值定义机构的局部力传递性能，以工作空间内局部力传递率的平均值作为全域力传递性能评价指标；以工作空间体积和全域力传递率的加权和为优化目标，采用小生境自适应遗传算法完成优化求解，获得最优尺度参数。与初始构形的性能对比分析表明，优化构形在力传递性能方面有35%的提升，具有更好的综合运动学性能。制作试验样机并完成相关实验，验证了所提尺度参数优化方法的有效性。最后探讨了多目标优化过程中不同的权重系数取值对优化结果的作用规律，发现选用均衡的权重可获得更佳的综合性能。

Performance Driven Optimal Design of Dimensional Parameters for a Shipborne Stable Platform

For the dimensional parameter optimization of 3-UPS&S parallel mechanism, an optimal geometric configuration of the shipborne stable platform is obtained to improve its kinematics performance by niche genetic algorithm with the workspace size and global force transmission rate as design indices. Specifically, a combination of numerical and analytical methods is used to determine the validity of constraint conditions such as branch chain length, joint rotation angle, singularity, etc., and to solve the workspace of the parallel stable platform. The minimum singular value of the inverse of force Jacobian matrix is used to define the local force transmission index, and the average value of the local force transmission rate in the workspace is used as the global force transmission index. Taking the weighted sum of the workspace size and the global force transmission rate as the optimization objective, the niche adaptive genetic algorithm is used to complete the optimization solution and obtain the optimal dimensional parameters. The performance comparative analysis with the initial configuration shows that the optimized configuration achieves a 35% improvement in force transmission performance and has better comprehensive kinematics performance. A test prototype is manufactured and related experiments are carried out to verify the effectiveness of the proposed optimization method for dimensional parameters. Finally, the law of the effect of different weight coefficients on the optimization results in the process of multi-objective optimization is discussed, and it is found that better comprehensive performance can be achieved by balanced weights.