绳牵引刚柔式波浪补偿并联机构的设计与建模

为了减少海上集装箱货物运输中风浪造成的损坏，提出刚柔混合驱动主动式波浪补偿并联机构. 基于刚柔混合并联机构的动定平台的矩阵旋转原理和几何封闭法建立位置逆解数学模型；利用空间几何原理构建机构位置正解数学模型；利用求导法则对位置逆解进行求导，建立速度雅可比矩阵与加速度的二阶影响矩阵；基于绳子是柔性变形体推导出系统刚度矩阵，探究影响系统刚度的因素和增加系统刚度的原则. 利用数值模拟仿真对运动学和系统刚度进行验证，结果表明位置正逆解的输入输出误差不超过实际误差的2.25%；发现理论仿真曲线和样机仿真曲线较吻合，误差不超过7.4%，验证了运动学模型的正确性；根据刚度矩阵发现刚度影响因素对系统刚度的影响规律. 通过对绳驱动刚柔混合驱动波浪补偿并联机构的实验验证，发现该机构的补偿效果均高于90%. 证明研究结果为刚柔混合主动式波浪补偿并联机构的运动和机构设计提供了理论支持.

Design and modeling of wire-driven rigid-flexible parallel mechanism for wave compensation

A rigid-flexible hybrid drive active parallel mechanism for wave compensation was proposed in order to reduce the damage caused by wind and waves in the transport of container goods at sea. The mathematical model of positional inverse solution was established based on the matrix rotation principle and the geometric closure method of the dynamic platform of rigid-flexible hybrid parallel mechanism. The mathematical model of the positional forward solution was constructed by using spatial geometry. The second order effect matrix of acceleration and velocity Jacobian was established by using the derivation rule to obtain the positional inverse solution. The system stiffness matrix was derived on the basis that the rope is a flexible variable body, and the factors affecting the system stiffness and the principle of increasing the system stiffness were explored. In addition, the kinematics and system stiffness values were verified by numerical simulation, and the input and output data errors of the inverse and positive solutions were not more than 2.25% of the actual errors. Results showed that the theoretical simulation curve and the prototype simulation curve coincided, and the error was not more than 7.4%, which verified the correctness of the kinematics model. The influence of stiffness factors on the stiffness of system was found according to the stiffness matrix. Finally, the parallel mechanism of the rope-driven rigid-flexible hybrid wave compensation was experimentally verified, and the compensation effect of the mechanism was more than 90%. Results provide theoretical support for the motion and the mechanism design of rigid-flexible hybrid active parallel mechanism for wave compensation.