Design And Analysis Of A Dual Output Multidirectional 3D Printing Parallel Robot

The rapid development of 3D printing technology has opened up a new era of"intelligent manufacturing" and has wide application prospects.It has become a research hotspot in the advanced manufacturing industry in recent years.At present,most of the 3D printers based on fused deposition technique can only print one product at a time,and mainly using series mechanism to form products in unidirectional layered printing mode.This type of printer has the disadvantages of low printing precision,poor stability and low efficiency in the practical application.It is easy to cause poor surface quality,mechanical properties,and interference problem when machining complex curved objects or repairing workpieces in unidirectional layered printing mode.Under this background,the research goal of this paper is to design a dual output multidirectional 3D printing parallel robot based on fused deposition technology,which can realize multi-output and multi-directional layered printing,save cost,and improve the precision and efficiency of 3D printing.To design a parallel robot that can meet the requirements of dual-output and multi-directional 3D printing,firstly,a new method of synthesizing parallel mechanism with articulated moving platform is proposed based on the Lie group theory,which can effectively enlarge the rotational workspace of the parallel mechanism.Using this method,a class of 3T2R type parallel mechanism with five degrees of freedom is designed,from which a 3T2R parallel mechanism was selected as the main body,and the dual output method used is the same limb shared driver,one set of drive system controls two identical output mechanisms,a dual output multidirectional 3D printing parallel robot is further designed.Then,the number of degrees of freedom of the 3D printing parallel mechanism is calculated by using the screw theory;the closed vector method is used to analyze the inverse kinematics and velocity matrix of the mechanism;the orientation workspace and attitude workspace of the mechanism were analyzed by using the inverse kinematics;the singularity and dexterity of the mechanism were analyzed and the static stiffness values of the mechanism at different positions in the workspace were calculated based on the velocity Jacobian matrix obtained by velocity analysis.Next,the orientation workspace and attitude workspace are determined as the optimization targets,and the optimal constraint conditions are established according to the influence of the structural parameters on the optimized target,the optimal structural design parameters is obtained based on genetic algorithm.Finally,the virtual prototype of the mechanism is established by using the optimized structural parameters,the freedom motion of the mechanism is simulated and verified in the ADAMS software,the path planning and simulation analysis of the planar printing and inclined plane printing are carried out based on the dual output and multidirectional 3D printing task.The results of the research and analysis show that the 3D printing parallel robot designed in this paper has large rotational workspace and can realize multidirectional printing.One machine can output two same printing tracks at the same time,indicating that the dual output can be realized,and the mecheanism is stable and reliable in the printing motion process.