In order to solve the bottleneck problems of multi 3D printing equipment,a fully-decoupled five degree of freedom (5-DOF)HKM was presented as the actuator of 3D printing.HKM consisted of 3-CPa RR parallel module and RRo serial module,and the parallel module consisted of three identical CPa RR limb chains,it might realize three-dimensional translations,the serial module RRo was used to adjust the print head posture,improve 3D printing process step phenomenon and in-terference problems.Screw theory was applied to analyze the kinematic characteristics of mechanisms and to calculate the degrees of freedom of 3CPa RR&RRo which were verified via the ADAMS soft-ware.The kinematic matrix of the hybrid mechanisms was carried out by using the D-H convention. The expression of the forward kinematics was deduced to obtain the Jacobian matrix and velocity equa-tions,and the analysis of singularity was carried out.Moreover,simulation model was built with AD-AMS,the velocities of the end-effectors of mechanisms were drawn.Thus,the validity of the theo-retical analyses was proved.%为解决多向3D打印装备瓶颈问题,提出一种完全解耦五自由度混联机构作为3D打印的执行机构,该机构由并联模块3-CPa RR和串联模块RRo组成,其中并联模块由3条相同CPa RR支链构成,可实现空间的三维移动,串联模块RRo用于调整打印头姿态,改善3D打印过程中的台阶现象、干涉问题.基于约束螺旋理论,分析了3 CPa RR&RRo机构自由度,并通过ADAMS建模对其进行了验证.然后运用D-H法求得混联机构的运动学方程,对机构的位姿正解表达式求导,得到了机构的雅可比矩阵和末端速度方程,分析了机构在工作空间内的奇异性问题,通过对模型运动仿真,绘制出了机构末端输出速度曲线,验证了上述分析的正确性.
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