RRR-RRPⅡ级杆组的等效系统动力学建模与分析

Analysis and establishing the equivalent system dynamics model of RRR-RRP Ⅱ degree bar-group

将等效方法与有限元方法相结合,基于等效元素集成法建立了RRR-RRPⅡ级杆组的动力学等效模型,给出了其动力学微分方程。建模时重点确定二阶张量、三阶张量和组装等效质量阵,建模过程简单、快捷,通用性强。对给定的RRR-RRP六杆机构进行了求解,给出了其动力响应曲线。通过实例表明,利用本文方法列写微分方程或由计算机进行解算比用传统方法解题效率高,弥补了用传统方法对杆组进行动力学分析时,由于系统运动关系复杂和人为分析技术差而极易出错的缺陷。

The equivalent method was combined with FEM in this paper, the equivalent dynamics model for RRR-RRP Ⅱ degree bar-group was established on the basis of EFEM and the dynamics differential equation was given. Accounting the key point of building dynamic model to be setting up 2 steps tensor Tia and 3 steps tenser Tibc and assembling the equivalent mass matrix. The process to establish dynamics model was simple and rapid and the generality is well. Analyzed and solved the dynamics model to the RRR-RRP 6 bars mechanism that has been given, the curves of dynamics responding of it was obtained. It is testified by dynamic analysis example that the method presented by this paper has a greater advantage and higher efficiency comparing with traditional method as describing the differential equation and calculating it by using computer and having redeemed the defect that it is easy to make as doing dynamic analysis because of the complexity of kinematics relation of system and the personal skill.