타이어 모델을 사용한 자율 드리프트 주행 제어 설계 및 분석

학위논문 (석사)-- 서울대학교 대학원 : 공과대학 기계항공공학부, 2019. 2. 이동준.본 논문에서는 Wheeled Mobile Robot(WMR)의자율드리프트 드라이빙 컨트롤러를 디자인 하고 분석하며, 이를 상용 프로그램인 CarSim을 사용한 시뮬레이션을 통하여 알고리즘을 검증 한다. 첫째로, WMR의 다이나믹스와 타이어 모델을 정의 하고, 이러한 모델로 인한 제약 사항에 대하여 논의한다. 다음으로, 사람의 관점에서 드리프트 드라이빙을 분석하고, 드리프트 드라이빙 제어기의 제어 목적을 정의한다. (차량의 방향과 요 각속도를 제어한다.) 드리프트 드라이빙 제어기는 고-레벨 제어, 목표 값을 찾기 위한 최적화 그리고 고-게인 제어로 구성된다. 다음으로, 제어하지 않는 속도에 대한 분석을 진행하였다. 마지막으로 제안한 알고리즘을 CarSim 시뮬 레이터를 이용하여 검증하였다. 정상 상태의 드리프트 시뮬레이션 결과와, 헤어핀 경로에 대한 드리프트 시뮬레이션 결과를 제시 한다.Control design and analysis of Wheeled Mobile Robot(WMR) autonomous drift-driving and the simulation experiment using the CarSim simulator are presented and the analysis of the controller proceeds. We first introduce WMR dynamics, tire model and problem formulation of the WMR. We then design drift-driving control using human strategy (control side slip angle and yaw rate). The drift-driving control consists of high-level control, optimization to find desired control input and high-gain control. We analyze the uncontrolled velocity dynamics and stability of the controller. The CarSim simulation results of drift-driving on steady-state equilibriums and the hairpin path with the desired yaw rate are provided.List of Figures - v List of Tables - vi Abbreviations - vii 1 Introduction - 1 1.1 Motivation and related works . . . . . . . . . . . . . . . . . . . . 1 1.2 Contribution of this work . . . . . . . . . . . . . . . . . . . . . . 3 2 System Modeling - 5 2.1 Model dynamics . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2.2 Tire model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 2.3 Problemformulation . . . . . . . . . . . . . . . . . . . . . . . . . 9 3 Drift-Driving Control Design - 10 3.1 High-level control . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 3.2 Optimization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 3.3 High-gain control . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 4 Analysis of Control - 17 4.1 Internal dynamics . . . . . . . . . . . . . . . . . . . . . . . . . . 17 4.2 Stability analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 5 Simulation Results - 25 5.1 Simulation setup . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 5.2 Steady-state drift-driving . . . . . . . . . . . . . . . . . . . . . . 27 5.3 Hairpin turn drift-driving . . . . . . . . . . . . . . . . . . . . . . 33 6 Conclusion and Future Work - 40 6.1 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 6.2 Future work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41Maste

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