Research On Dynamics And Control Of A Single Ball Wheeled Mobile Robot

The single spherical robot is a kind of inherently unstable dynamic balancing robot.Contacting with ground at one point,the single spherical robot can move around flexibly and also it has the characteristics of multi variable,highly nonlinear and time-varying.In recent years,it has become a hotspot in the field of wheeled robot research.Compared to traditional wheeled robots,the single spherical robot has almost zero turning radius which makes it can turn to any direction at any time.Meanwhile,the single spherical robot has a broad application prospect since it has thin and simple mechanism,can work in the narrow space.This paper mainly discusses the dynamics and controller model of single spherical robot,laying a theoretical foundation for the realization of the robot's stable self-help movement.Based on the study of the motion law of the single spherical robot,the motion of the robot is divided into three planes of inertial coordinate system,and then the kinetic energy and potential energy of the robot are modeled respectively in these three planes.According to the Lagrange equation,the dynamic model of the robot is established.And the nonlinear mathematical model of the robot is linearized near the equilibrium point to obtain the corresponding state equation.On the basis of the equation of state,the controllability and observability of the system are analyzed.According to research on balance control of robot,this paper puts forward a control algorithm of LQR combined with PID.The XOZ and YOZ plane of the robot are optimized by LQR algorithm,and the PID control algorithm is applied to the XOY plane of the robot.And the control algorithm is applied on the state equation of the robot system model in the Matlab-Simulink software platform.After the control algorithm obtain a satisfying control effect,the co-simulation platform is established by using the dynamics software Adams and the control simulation software Matlab/Simulink.After repeated adjustment of parameters,the results show that the designed controller can achieve the desired results for the strongly nonlinear robot system control.