학위논문 (석사)-- 서울대학교 대학원 : 기계항공공학부, 2015. 2. 김유단. ; Unmanned aerial vehicle (UAV) has developed to perform military missions including patrol, surveillance, and reconnaissance. Recently, the applications of UAV are expanding to the private markets of UAV agriculture, aerial photography and etc. For these various applications, collision avoidance of UAV is an essential problem, because collision to obstacles may cause not only mission failure but also destruction of UAV and fatal accident including loss of human life. In this study, modified A* path planning algorithm is proposed for UAV systems. In various robot applications, standard A* algorithm is widely used, which does not apply dynamics of UAV. Therefore, the results from the path planning algorithm should be post-processed to reflect the dynamic constraint of an UAV such as limited turning angle. To deal with this problem, search direction achievable by the UAV is considered in the proposed A* algorithm. The proposed algorithm can be implemented on the on-board system of the UAV in real-time, and does not need post processing to follow the result of path planning. Nonlinear guidance algorithm and PID controller to follow the path are also designed. The performance of the proposed algorithm is demonstrated using numerical simulations. Six degree-of-freedom simulation model was obtained by system identification flight test. Finally, the integrated algorithm is verified by the flight test. ; 1. Introduction 2. Guidance and Control of UAV 3 2.1 Guidance of UAV for Path Following 3 2.1.1 Longitudinal Guidance 3 2.1.2 Lateral Guidance[10] 4 2.2 Autopilot system of UAV 6 2.2.1 Longitudinal Control 6 2.2.2 Lateral Control 7 3. Path Planning of UAV 9 3.1 A* Path Planning Algorithm 9 3.2 Modified A* Path Planning Algorithm for UAV 13 3.2.1 Problems of Standard A* Search 13 3.2.2 Search Candidate Point Selection 14 3.2.3 Cost and Heuristic Function Design 18 3.2.4 Modified A* Path Planning Simulation 21 4. Numerical Simulation 26 4.1 UAV System Modeling 26 4.1.1 UAV Model 26 4.1.2 UAV System ID 26 4.1.3 Longitudinal UAV System Model 27 4.1.4 Lateral UAV System Model 28 4.2 Linear Model Based A* Simulation 28 4.2.1 Simulink Simulator Block 28 4.2.2 Angle of Sight Target Point Calculation 34 4.2.3 Simulation Result 36 5. Flight Test 44 5.1 UAV System 44 5.1.1 UAV System Introduction 44 5.1.2 Flight Control Computer 47 5.2 Flight Test Preparation 49 5.3 Flight Test Result 49 6. Conclusion 56 ; Master
Development of A* Real-time Path Planning Algorithm of UAV Considering Collision Avoidance ; 충돌회피를 고려한 무인항공기
2015-01-01
Hochschulschrift
Elektronische Ressource
Englisch
BASE | 2014
|A real time collision avoidance algorithm
Online Contents | 2000
|