Research And Design Of Two Wheeled Self-Balancing Car Control System

With the energy crisis brought by the traditional means of transport,the problems of traffic congestion and environmental pollution have become increasingly prominent,and people’s demand for new-type vehicles has become increasingly urgent.Two wheeled self-banlancing car is small and easy to carry,and the use of battery-powered will not produce exhaust gas.It is the focus of research in the field of transportation.At the same time,the two wheeled self-balancing car is a system capable of maintaining a steady conditions under a dynamic state and unable to reach a steady conditions under a static state.It has a strong coupling,nonlinear,under-driven,multivariate features.Therefore,we can validate various control algorithms on this platform of two wheeled self-balancing car,which has a great theoretical significance.Based on the research status of two wheeled self-balancing car at home and abroad,this paper studies on attitude angle detection and self-balancing control of the car.First of all,using Newtonian mechanics to establish a mathematical model of the car’s wheels,body and motor,and based on the relationship between the three to establish a model of the overall system of the car.Secondly,the car model is linearized at the equilibrium position to obtain a simplified model.Observability and controllability analysis of the simplified model and adopt PID control theory to design the balance controller to the car system.The attitude angle of the car includes body tilt angle and yaw angle.It is an important variable of the car controller design.Therefore,the attitude angle accuracy is particularly important.It is proposed in this paper that the attitude angle is represented by the quaternion method so as to avoid the situation that the singular value appears when using the Euler angles to represent the attitude angle,And the data collected by the attitude sensor of the car is fused by using the extended Kalman filter(EKF)principle to obtain a more accurate attitude angle.Finally,build two wheeled self-balancing car hardware platform.The design of two wheeled self-balancing car drive circuit,the main control circuit,detection circuit,wireless communication circuit,and the preparation of the various parts of the program to ensure that the car can work properly.The Matlab software was used to simulate the car PID control and extended Kalman filter data fusion.The results show that the car PID controller can control the car well,and the extended Kalman filter(EKF)makes the car attitude angle more accurate.In the physical display of the two wheeled self-balancing car built,the car can maintain a good balance of control.