以提高多自由度并联机构的运动性能为目标,探索柔顺双稳态机构在克服并联机构力奇异问题中的应用。提出一种双稳态凸轮柔顺机构,利用双稳态机构在非稳态位形的非零内力,为并联机构提供柔顺过驱动输入,利用柔顺过驱动输入消除并联机构在运动奇异和力奇异位形时的运动或操作力不确定性。以平面五杆2-DOF并联机构为例进行了机构工作空间分析、运动奇异位形分析、以及力奇异位形分析。计算结果证明采用提出的双稳态凸轮柔顺机构能实现该平面2-DOF机构奇异位形的控制。
For the sake of improving the properties of parallel mechanisms, the application of compliant bi-stable mechanism for overcoming the singularity of kinematics and force manipulation of parallel mechanism are investigated. A kind of cam compliant mechanism with hi-stable property is proposed. The bi-stable compliant cam mechanism can provide nonzero internal force in unstable configuration for a parallel mechanism, thus the nonzero internal force can be used to remove the uncertainty of motion or manipulation force. As an example, a planar five bars 2-DOF parallel mechanism is discussed, the working space is drawn and the motion and force manipulation singularity are analyzed. The simulation and calculation results show that the bi-stable compliant cam mechanism can control the planar five bars 2-DOF parallel mechanism at the singularity configuration.