Research On Trajectory Tracking Of Reptile Printing Robot Based On Model Predictive Control

Aiming at the problems of too large size of traditional printing equipment,limited printing format,and inconvenience to carry around,this paper has designed a two-wheel differential drive reptile printing robot that can move freely on the paper,which greatly reduces the size of the printer and prints.The format is no longer constrained by the mechanical structure.The printing effect of the reptile printer is closely related to its trajectory tracking controller.The inkjet frequency of the reptile printing robot nozzle requires time parameters.The trajectory tracking requires tracking the path with time as the parameter.The combination of the two means that the reptile printing robot needs to be at a given time point.Inkjet appears at the desired trajectory position,which can greatly improve the quality of inkjet,so this article focuses on the trajectory tracking problem of reptile printers.Among many trajectory tracking control laws,model predictive control has its rolling optimization strategy and can make up for the model mismatch,uncertainty caused by disturbance factors,good dynamic performance,can effectively deal with multi-variable and multi-constraint problems,and improve output through feedback correction.The robustness of the system and other advantages,this paper based on the design of the crawler printing robot model,based on model predictive control to carry out in-depth research on the trajectory tracking of the crawler printing robot.This paper studies linear time-varying model predictive control(LTV MPC),transforms nonlinear systems into linear time-varying systems,derives LTV MPC algorithm formulas,and at the same time transforms LTV MPC optimal problems into standard quadratic programming problems that are easy to solve,And the conversion of constraint processing.A suitable LTV MPC controller is designed for the trajectory tracking control of the kinematic model of the reptile printing robot.The simulation results verify that the LTV MPC not only achieves fast desired trajectory tracking,but also ensures the stability of the tracking process.In the study of nonlinear model predictive control(NMPC),this paper analyzes the first-order necessary conditions of the optimal control problem,designs the NMPC controller based on the dynamic error model of the crawler printing robot,establishes the optimal control problem of the trajectory tracking of the crawler printing robot,and expounds NMPC solution process and stability analysis.This paper introduces a fast NMPC algorithm for solving optimization problems based on the first-order necessary conditions for optimization—C/GMRES.The C/GMRES algorithm is improved by introducing multiple shooting methods and obstacle function methods,and the two algorithms are derived.The first-order optimal necessary condition of the optimal control problem of trajectory tracking is to carry out the trajectory tracking simulation experiment on the improved C/GMRES algorithm.