Research On Dynamics Modeling And Control Strategy Of 3-PUU Parallel Manipulator

Manufacturing industry is the foundation of the state.With the national 2025 policy put forward,to improve the levels of manufacturing and automation has become a general trend,the rapid development of robot technology is one of the important embodiment.The parallel robot,as a special member of the robot family,has been widely used in the area of small objects and large stack quick grabbing,Against the existing problems in structure design and control,this thesis takes the research for the 3-PUU parallel robot in the aspects of kinematics,workspace,dynamics,and control strategy under the main line of motion control.First of all,the structure and the degree of freedom of 3-PUU parallel robot was analyzed.At the same time,using the analytical method to analyze the robot's forward and inverse kinematics,and solve the Jacobi matrix of kinematics,which is the key point.On the basis of the surface-sweeping analysis combined with mechanical structure of shape and physical constraints analysis method,the analytical expression of the boundary surface obtained which expresses the relationship between the size of the mechanical structure and the workspace dimension,solving the problem that the numerical analysis method cannot solve,and it provides theoretical basis for the design of the standard space dimension.Then,taking the constraints of hooke joint into consideration,formed a complete research system in kinematics category.And then,on the basis of kinematics analysis,using the method of virtual work principle to complete the dynamics modeling of 3-PUU parallel robot,then required torque of the three drive motor can be obtained in a specified path,then programming in MATLAB,it can obtained output torque diagram of drive motor under the specified path;then,on the Adams software,a dynamics simulation software,simulation analysis is done,and the simulation results are compared with the result obtained by programming with MATLAB software under the same trajectory to verify the validity of the theory analysis.Then,the control strategy in the field of robot is studied.First,the common control strategies are classified,The advantages and disadvantages of each are compared and analyzed,choosing their respective representative that traditional PID control strategy belongs to the category of kinematics control,computed torque control belongs to the category of control based on dynamic model and fuzzy control,their control idea and control process has carried on the analysis,building up joint simulation platform between ADAMS and MATLAB,the control effects of the three control algorithms are simulated and compared.Taking the trajectory tracking accuracy as the control target,it obtained that the fuzzy control strategy based on dynamic model can have better control effect.Finally,experimental prototype verification is performed.The workspace of the 3-PUU parallel robot is scanned in three dimensions,Verifying the correctness of the previous theoretical analysis,it also provides a solid theoretical foundation for the design of robot mechanism in engineering practice.