改进型Delta并联机构的弹性变形分析与仿真

摘要

利用机构外载荷作用下势能Hessian矩阵定义改进型Delta并联机构的刚度,并建立考虑机构形位变化和外载荷作用下各构件弹性变形的机构刚度映射模型,进而利用该模型得到不同运动位姿和不同外载荷下,机构末端的弹性变形.同时,结合ADAMS软件的ADAMS/flex模块产生柔性体,通过替换原有的刚性体为柔性体,建立改进型Delta并联机构刚柔混合体虚拟样机,借助虚构件实现添加驱动和各个构件之间的运动副,最后仿真出不同位置和外载荷条件下机构的弹性变形,从而实现相互验证上述理论计算和仿真的正确性.%Based on the stiffness matrix of the modified Delta mechanism that is defined as the Hessian matrix of a potential, a stiffness mapping model of the mechanism, which reckons the influence of the change of the mechanism;s configuration and all parts' elastic deformation under the constraint force, was established.By using the model, the elastic deformation of the mechanism under different positions and different external loads could be obtained.At the same time, a flexible bar could be produced by integrated the ADAMS/flex module of the ADAMS software.Some original rigid bars could be replaced by these flexible bars;so, a rigid flexible hybrid virtual prototype of modified delta parallel mechanism was established.By virtual component, the drive and the motion pairs of the various bars were added to implement.At last, elastic deformation of the model is simulated in ADAMS software under different moving position and external load, so, theoretical calculation and simulation are verified mutually correct.