Design And Research Of A Multidirectional 3D Printing Parallel Manipulator

As a new type of manufacturing technology in recent years,3D printing technology has a wide range of applications because of its unique advantages in manufacturing products with complex structure,improving speed of manufacture,et al.However,most of the 3D printers can only move along the vertical direction for the reason that their printing heads posture are designed to be fixed,which will result in some problems of step-shaped surface,low mechanical properties,low printing speed,interference between the head and the objects,and poor stability when processing the objects with complex geometry or modifying the workpiece.To solve the above problems,this paper focuses on designing a new multidirectional 3D printing manipulator through combining the fused deposition(FDM)technology with the parallel mechanisms.A class of parallel 3D printers which are capable of printing along different directions is proposed based on the Lie group theory.The articulated moving platforms are used in proposed mechanisms to obtain larger rotational workspace,which provides a feasible solution to solve the problem of limited rotational capability for the traditional parallel mechanisms.A five degrees of freedom(DOF)parallel mechanism with 2-dimensional rotations is designed,which can be applied in the multidirectional printing.First,the inverse kinematics of multidirectional 3D parallel robot is analyzed by using constrained length of the bars,and the orientation workspace and attitude workspace of the robot is analyzed according to the analytical solution of the inverse kinematics analysis.Second,the Jacobian matrix of velocity of the multidirectional 3D print parallel robot is established by using screw theory.The dexterity and static stiffness are analyzed based on the proposed Jacobian matrix.Next,the dimensional synthesis of the multidirectional 3D parallel robot is carried out based on genetic algorithm and a set of optimized data is selected as the dimension parameter of the prototype.Then,the trajectory simulation of the virtual prototype of the robot is conducted in the horizontal and inclined plane by using the ADAMS software.Finally,the hardware system of the multidirectional 3D parallel robot prototype is selected,the control scheme of the prototype is designed,the trajectory planning and the control of the print head is carried out,and the product is printed successful by using the prototype.The results show that the designed multidirectional 3D printing robot possesses the ability of rotating with large rotational angles,multidirectional-layered manufacturing and processing products with general precision,which are significant for the multidirectional 3D printing.