Formation Control Of Under-actuated Wheeled Mobile Robot

At present,most of the formation control algorithms proposed in the study of formation control are based on the moving body models described by single integral or double integral.This thesis focuses on the design and experimental verification of the formation control algorithms for under-actuated wheeled mobile robots.The control algorithm realizes formation control of the robot's position and speed(translation state),and concerns on the stabilization of under-actuated dynamics or internal dynamics(angle dynamics).In this thesis,the two wheeled self-balancing vehicle,with non-minimum phase characteristics,is chosen as the research platform.Main work and study on the platform are as follows:The non-minimum phase characteristics of the under-actuated wheeled mobile robot are analyzed.Built the model of the under-actuated wheeled mobile robot,and the characteristics of the model are analyzed.By analyzing the input-to-state stability(ISS)of the internal dynamic system or zero dynamic,the systems of under-actuated wheeled mobile robots are divided into minimum phase systems and non-minimum phase systems.The formation control algorithm for the under-actuated wheeled mobile robots is designed based on the causal stable inversion(CSI)method,according to the non-minimum phase characteristic of the under-actuated wheeled mobile robot.The thesis designed the formation control algorithm based on motion synchronization control theory: If it is a minimum phase system,the formation control algorithm based on double integral model can be chosen;If it is a non-minimum system,the thesis designed the suitable formation control algorithm according to the method of the casual stable inversion,in order to ensure the convergence of formation control error,at the same time,the internal dynamic keep stable.And the algorithm is simulated and verified.The results testified the feasibility of the algorithm.The proposed formation control algorithm is experimentally verified.The experimental verification platform for under-actuated wheeled mobile robot formation control is built.Through the addition of sensors and communication network,the information interaction among wheeled mobile robots is achieved,met the requirements of formation control experimental verification.The thesis verified the designed formation control algorithm on the experimental platform,tested the robustness of the wheeled mobile robot formation system,analyze the experimental results and then optimize the formation control experiment.