Performance Analysis And Optimization Of Delta Parallel Mechanism

Compared with the series mechanism,the parallel mechanism has the advantages of high speed,small inertia and high precision.It has been widely used in many fields such as medical,electronics and food.The Delta parallel mechanism is a typical representative in the parallel mechanism.The Delta parallel mechanism has the characteristics of compact structure,high speed and high precision,and has become a research hotspot of current institutional science.The kinematics,dynamics,stiffness,performance optimization and application of the Delta parallel mechanism is studied in this paper.The Delta parallel mechanism is introduced,and the structure is simplified.The degree of freedom of the Delta parallel mechanism is analyzed by the spiral theory.Using the closed-loop vector method to establish the inverse kinematics equation of the Delta parallel mechanism,and the kinematic inverse solution is obtained by numerical calculation.The size of the working space of the Delta parallel mechanism is solved by the numerical method:The static analysis of the Delta parallel mechanism is carried out by the method of dismantling and Newton’s law,and the restraining reaction force of each motion pair is obtained.The dynamic model of the Delta parallel mechanism is established Based on the virtual work principle method,and the curve of the driving torque is obtained by numerical calculation.,Obtain the mass matrix of the mechanism according to the kinetic equation.Based on the traditional stiffness matrix,which only considers the active joint stiffness,the deformation of the rod also has an effect on stiffness.The stiffness matrix of the Delta parallel mechanism is derived by the analysis of the deformation of the part.The minimum singular value of the stiffness matrix is used as the evaluation index of the stiffness performance of the Delta parallel mechanism,and the stiffness performance curve of the Delta parallel mechanism is obtained by numerical analysis.The kinematics and dynamics performance evaluation indexes of the Delta parallel mechanism are proposed,and the objective function of the kinematics and dynamics of the mechanism is obtained.Under the constraint of the workspace and the speed,the multi-objective optimization of the kinematics and dynamics of the mechanism is achieved by NAGA-Ⅱ,and the optimal scale parameters are obtained.The Delta parallel mechanism is applied to the 3D printer.The positioning accuracy of the 3D printing robot is analyzed.The mathematical model of the positive error solution is established,and the influence of each error on the mechanism precision is analyzed.Based on the error model,the pose accuracy compensation model is established,and the correctness of the model is verified by an example analysis.