Research On Motion Control System Of Omnidirectional Mobile Robot Based On Linear Active Disturbance Rejection Control

In recent years,the role of mobile robots in inspection operations,smart electrical appliances,and unmanned driving has become increasingly apparent.Compared with wheeled robots,omnidirectional mobile robots have higher mobility and more degrees of freedom.Mecanum wheels,as a special wheel structure,can use different combinations to complete the movement of the mobile platform in any direction in the plane.,Can meet the working requirements of indoor narrow and flat ground.Due to the particularity of the mobile platform structure,omnidirectional mobile robots are susceptible to various disturbances such as changes in surrounding environmental conditions and inaccurate modeling during practical applications.Therefore,designing a stable motion control system for the mobile platform has become a research difficulty.In this paper,the Linear Active Disturbance Rejection Control algorithm is used to study the motion control system of the four-wheel omnidirectional Mecanum-wheel robot mobile platform.The main research contents are as follows:Firstly,the research background and significance of this topic are described,and the research status of mobile robot and several mainstream motion control algorithms are analyzed,summarized and briefly introduced.The development and application of the theory of Active Disturbance Rejection Control are described,and the main research content of this topic is finally determined.Secondly,the kinematics model of four-wheel omni-directional Mecanum wheeled robot under ideal conditions and the dynamics model obtained by Lagrange method are established by briefly describing the kinematics and dynamics principles of the robot chassis.The characteristics of the dynamic system model of the mobile robot are summarized and analyzed,and the relationship between the motion direction of the mobile robot and Mecanum wheeled robot is given The relationship between wheel force and steering lays a foundation for the subsequent controller design.Thirdly,assuming that the four-wheel omni-directional Mecanum wheeled robot runs on a flat and smooth ground,considering the internal and external disturbances in its motion control system,a trajectory tracking controller based on linear active disturbance rejection algorithm is designed.The control system is mainly composed of a linear extended state observer and an controller.After analyzing the stability of the system,the stability of the bounded input and bounded output of the estimation error and the exponential stability of the tracking error are confirmed.The tracking performance of the mobile platform under a given trajectory is verified by simulation,and the simulation results prove that the control algorithm has good disturbance rejection performance.Fourthly,the motion control system platform of four-wheel omnidirectional Mecanum wheel robot is developed and designed,and the overall structure of the motion control hardware system is designed,which is mainly divided into the following modules: main controller,motor drive module,encoder speed measurement module,inertial measurement unit,serial communication module and positioning navigation module.The main functions of each module are analyzed,the type selection and circuit design are carried out.Then,according to the hardware structure design,the software program modules are divided.Using the design idea of modular programming,each module is designed,including the motor drive module software design,motion control function software design,serial communication software design,data acquisition and processing of encoder and inertial measurement unit.Last but not least,the designed motion control system is verified on the four-wheel omnidirectional Mecanum wheel robot,which proves the effectiveness of the designed control system.