提出了一种以新型三自由度冗余驱动并联机构4-PRP作为定位模块,串联上三自由度并联机构3-UPS&PU来共同实现六自由度运动的新型混联机床的机构设计方案。首先,运用螺旋理论分析了该机床实现3T3R运动原理,计算出该机构的自由度。然后,利用解析矢量法及几何关系建立机构位置逆解方程,运用影响系数法建立了一阶运动影响系数矩阵—Jacobian矩阵和二阶影响系数矩阵—Hessian矩阵,建立了完整的运动学模型。最后,应用MATLAB对逆解方程进行求解并利用ADAMS对求解结果进行仿真验证,验证了运动学模型的正确性及机构的可行性。
A structure scheme for a novel 6 - DOF hybrid machine tool (HMT) is proposed. In this scheme, a novel 4 - PRP redundantly actuated parallel mechanism is proposed as the position module, which can realize three motion, with assistance of the 3 - UPS&PU parallel mechanism, 6 - DOF machining can be re- alized. Firstly, the three - dimensional translations and three - dimensional rotations motion of this machine tool are analyzed based on screw theory. Then, the inverse displacement analysis model is provided by using analyti- cal methods and the geometric relation of the mechanism. And the first -order influence coefficient matrix - Jacobian matrix and the second order influence coefficient matrix - Hessian matrix and complete kinematics model are established by using the influence coefficient method. At last, the position inverse solution is ob- tained by using MATLAB and the results simulation verification is carried out by using ADAMS, which verify that the correctness of the inverse displacement analysis model and the realizability of the mechanism.