Control System Study Of The Self-balancing And Manned Electric Unicycle

This dissertation studies the self-balancing and manned electric unicycle which can be regarded as a kind of vehicle for transportation. In this paper, researches on the electric unicycle system has been carried on which are the model and analysis, accurate attitude information acquisition, posture balancing control and motor control strategy.First of all, The dynamic model of an electric unicycle was set up using Newton method based on analyzing the actual operation and reasonable assumptions of its motion process. The stability, controllability and observability analysis of the linearized model are carried out, and the influence is analyzed which is changes of model parameters because of different rider. The theoretical basis for the electric unicycle control is provided by the established model and related dynamics analysis.Secondly, based on the analysis on the characteristics of common inertial components and the control requirements of electric unicycle, the gyroscope and accelerometer are selected to measure attitude information of electric unicycle. An appropriate attitude updating algorithm and filtering fusion technology are used to obtain the more accurate attitude information, and then the foundation is established for the realization the posture balance control of the electric unicycle.Thirdly, in order to improve the control performance of posture balance controller, the related knowledge of fuzzy control is used to introduce the nonlinear characteristic of into linear PD controller and to make up controlled system. Combining with the nonlinear characteristic and the actual operation condition of electric unicycle, fuzzy control rules table is formulated. Starting from the small angle and pulse jamming simulation experiments are carried on to verify the dynamic and static performance of the proposed self-tuning fuzzy PD controller, which are compared with the linear PD controller.Finally, combining with the self-tuning fuzzy PD controller and vector control strategy of permanent magnet synchronous motor, the control system of self-balanced manned electric unicycle is established, which includes the attitude loop, speed loop and current loop, and the posture balancing control electric unicycle is realized. On this basis, according to the speed control and load mutation problems, the control strategies are proposed to further improve the system dynamic performance and anti-interference ability. The experimental platform of the self-balancing and manned electric unicycle has been built and all the hardware and software systems have been deeply introduced. Then several experiments are carried out on the basis of the above theoretical and simulation studies.