Research On Several Issues Of A Variable Structure Wheeled Robot

In this paper,a kind of two-wheeled robot is studied,which can switch between bicycle mode and Segway mode.Bicycle and Segway have their own advantages.Bicycle has advantages on rough and narrow road,however Segway has more advantages in running on flat and spacious road.The variable structure two-wheeled robot performed in this paper has a strong practical value.And the two-wheeled vehicle has the characteristics of static instability,under-actuation and non-holonomic constrains,these characteristics make it has theoretical significance for its study.The motion relationship and mechanical coupling characteristics of the variable structure wheeled robot are analyzed firstly,including kinematics analysis of general motion forms and a kind of mode switching(synchronous rotation of two forks)process of the variable structure wheeled robot.And the dynamics model based on Appell equations and Chaplygin equations are proposed for both types of motion forms of the variable structure wheeled robot,respectively.And the numerical simulation based on Matlab is proposed,and the ADAMS solid model simulation based on Adams are achieved.Further,the contrast between the Matlab simulation result and the Adams simulation result are finished,and the validity of the two dynamics models are testified.Secondly,based on the two dynamics models of the mode switching process,the sliding mode controllers under the condition of fixed the two forks are designed respectively.And the effectiveness of the slide mode controllers based on the two dynamics models is verified with Matlab and Adams joint simulation.Thirdly,in order to achieve mode switching and keep balance of the variable structure wheeled robot,the influence of the sliding surface coefficients and the approaching law function parameters on the controll effect of the controller are studied.Further,a fuzzy sliding mode controller is designed.In the process of mode switching,the parameters of the sliding mode controller tuned with fuzzy rules.And the steady switching between Segway mode and bicycle mode of the robot is realized.Lastly,the control system and the information acquisition system are designed and achieved.