摘要
设计了3种七支链并联机构,并提出了数值迭代与解析方法相结合的正运动学求解思路。引入辅助支链,推导出支链协调方程,再运用数值迭代方法由协调方程反求辅助支链的长度,并研究了数值迭代法初值偏差与迭代效率的关系。在求得辅助支链和实际支链长度的基础上提出一种全解析算法,通过消去高次项得到四组多元一次方程组,由四组多元一次方程组推导出动平台位姿唯一的解析表达式。通过虚拟试验对该半解析算法进行了验证,结果证明此算法具有准确、高效的特点。
It introduces three kinds of seven-branches parallel mechanism, describes a method for forward kinematics solution, which combines analytical method and numerical method. Adding auxiliary branches, it derives coordination equations. Based on numerical iterative methods, it obtains the length of branches. Aiming at the initial value selection, it analyzes the relationship between initial value and iterative efficiency. Combining the length of actual branches with auxiliary branches, it proposes an analytical method, eliminates high order terms, obtains four groups of multiple equations. Virtual tests prove that this semi-analytical algorithm is precise and effective.
引文
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