Synthesis Of Several 3-DOF Parallel Mechanism With Continuous Motion

The application of parallel mechanism in the field of high precision further promotes the improvement of the performance requirements of parallel mechanism.With the continuous motion of mechanism,it has important significance of trajectory planning and kinematics calibration,and it will be further affect the mechanism of the precision and error of end effector pose.However,because of its unique structure of the traditional parallel mechanism,it leads to the existence of instantaneous and continuous motion in the process of movement,and the instantaneous motion of rotation restricts the end effector trajectory planning mechanism.It has important significance how to design a parallel mechanism of continuous motion.This paper focuses on several three degrees of freedom parallel configuration synthesis problems with existence of continuous motion.A method is proposed for continuous motion of three degrees of freedom parallel configuration synthesis and the structural synthesis of mechanism is analyzed,the main contents include the following:Based on the screw theory,the continuous motion of necessary and sufficient conditions of parallel mechanism are developed by using the mathematical formula,combining space line geometry and mechanism topology synthesis method,a method based on a continuous motion of three degrees of freedom parallel mechanism configuration synthesis is developed.Based on the proposed mechanism synthesis method,the synthesis of 2T1 R,1T2R and 3R three degree of freedom parallel mechanism with continuous motion has been down respectively,a class of symmetric and asymmetric three degree of freedom parallel mechanism is presented.According to the three degree of freedom parallel mechanism of continuous motion,analysising and researching on the typical model mechanism based on the screw theory,determining the existence continuous shaft spatial position of mechanism,and simulating by using Adams simulation software.The comparative data shows that the characteristics of the integrated mechanism satisfy the goal of the synthesis,and the proposed method is feasible.