Development Of The Self-balancing Unicycle Control System

The air pollution and traffic congestion is becoming serious nowadays. The self-balancing unicycle has advantages of small volume, convenient to carry and flexible movement so more and more people choose it as a kind of traffic tool. Moreover, the self-balancing unicycle has characteristics such as high order, nonlinear, under actuation and static unstable, the research of modeling and postural control of it have become hotspots in the field of robotics research.On the basis of reading a large number of related papers at home and abroad, this paper focuses on four aspects:dynamics modeling, posture detecting, posture control algorithm and motor control strategy of the self-balancing unicycle. The details are as follows:Firstly, through analyzing the balance principle of the unicycle system and reasonable assumptions, the dynamic equation of each part of the unicycle system are established. On the basis of system dynamics equation, the system’s stability, controllability and observability are analyzed. The above studies provide a theoretical basis for postural stability control algorithm.Secondly, based on the analysis of inertial measuring element, we select the accelerometer and gyroscope to get the posture information. In order to get accurate information about the posture, the attitude algorithm of sensor filtering methods are studied.Thirdly, the control strategy to keep the unicycle balanced is studied. Considering the feasibility of the attitude control strategy in the actual system, this paper designs a linear quadratic regulator (LQR) optimal controller. Based on LQR theory study, The self-balancing unicycle attitude control of LQR method is designed. At the same time, it’s carried on the simulation to verify the effectiveness. By combining the LQR control method of permanent magnet synchronous motor vector control method, the three-loop control system including position loop, speed loop and current loop is designed to achieve stable control of unicycle working attitude.Finally, the experimental platform of the self-balancing unicycle system is built to verify the feasibility and effectiveness of the methods that this paper proposed. The computer software and mobile client of the self-balancing unicycle are designed to increase the intelligence of the self-balancing unicycle system.