Design and Motion Characteristics Analysis on a Dynamically Reconfigurable Rotorcraft
ZHAO Changli1, GUO Da1, WANG Xuqiao2, YIN Pengfei1,2
1. Institute of Aeronautics and Astronautics, Tianjin Sino German University of Applied Technology, Tianjin 300350, China; 2. Robotics Institute, Civil Aviation University of China, Tianjin 300300, China
Abstract：A dynamically reconfigurable rotorcraft is proposed to solve the problem that the rotorcraft can't pass continuously a narrow space along its path due to its body structure limits. The motion response to the space change is achieved by changing the body structure, and the continuous mobile operation performance of the rotorcraft in a complex environment is improved. The system with a chained modular structure can change its 2D configuration by rotating joints. The kinematic model of the airframe is established according to the structural characteristics and motion control mode, the spatial transformation matrix is derived based on the D-H (Denavit-Hartenberg) rule, and the changed center of gravity is also obtained. A solution method of configuration transformation based on geometric, dynamic and control response constraints is proposed, and the corresponding boundary conditions are derived. The experiments demonstrating flight stability, maneuverability and critical configuration are conducted. The results show that the attitude of the rotorcraft is stable without obvious mutation, and the maximum variations of different axes are all within 4° during the whole configuration transformation. The flight control remains smooth and the tracking control response can be completed in 0.1 s when approaching the critical configuration. The angle set of the critical configuration with controllable attitudes is 180°, 180°, 113° in the experiments. Geometric evaluations show that the passing radius can be reduced by 21.89% in the fixed heading mode, and the maximum passing radius can be reduced by 67% when combining with heading control. The rotorcraft can complete dynamic reconfiguration when passing through a narrow gap.
[1] 全权,李刚,柏艺琴,等.低空无人机交通管理概览与建议[J].航空学报, 2020, 41(1):No.023238. Quan Q, Li G, Bai Y Q, et al. Low altitude UAV traffic management:An introductory overview and proposal[J]. Acta Aeronautica et Astronautica Sinica, 2020, 41(1):No.023238. [2] 张启瑞,魏瑞轩,何仁珂,等.城市密集不规则障碍空间无人机航路规划[J].控制理论与应用, 2015, 32(10):1407-1413. Zhang Q R, Wei R X, He R K, et al. Path planning for unmanned aerial vehicle in urban space crowded with irregular obstacles[J]. Control Theory & Applications, 2015, 32(10):1407-1413. [3] 闫斌斌,李勇,戴沛,等.基于增强学习的变体飞行器自适应变体策略与飞行控制方法研究[J].西北工业大学学报, 2019, 37(4):656-663. Yan B B, Li Y, Dai P, et al. Adaptive wing morphing strategy and flight control method of a morphing aircraft based on reinforcement learning[J]. Journal of Northwestern Polytechnical University, 2019, 37(4):656-663. [4] 张杰,吴森堂.一种变体飞行器的动力学建模与动态特性分析[J].北京航空航天大学学报, 2015, 41(1):58-64. Zhang J, Wu S T. Dynamic modeling for a morphing aircraft and dynamic characteristics analysis[J]. Journal of Beijing University of Aeronautics and Astronautics, 2015, 41(1):58-64. [5] 聂瑞.变体机翼结构关键技术研究[D].南京:南京航空航天大学, 2018. Nie R. Research on key technologies of morphing wing structures[J]. Nanjing:Nanjing University of Aeronautics and Astronautics, 2018. [6] 李文成.变体飞行器动力学建模与稳定性分析及控制[D]. 南京:南京航空航天大学, 2017. Li W C. Dynamics modeling, stability analysis and control of morphing aircraft[J]. Nanjing:Nanjing University of Aeronautics and Astronautics, 2017. [7] 程昊宇,董朝阳,王青,等.变体飞行器的非脆弱有限时间鲁棒控制器设计[J].控制与决策, 2017, 32(11):1933-1940. Cheng H Y, Dong Z Y, Wang Q, et al. Non-fragile finite-time robust controller design for morphing aircraft[J]. Control and Decision, 2017, 32(11):1933-1940. [8] 梁小辉,王青,董朝阳.基于切换系统的变体飞行器鲁棒自适应控制[J].北京航空航天大学学报, 2019, 45(3):538-545. Liang X H, Wang Q, Dong Z Y. Robust adaptive control for morphing aircraft based on switching system[J]. Journal of Beijing University of Aeronautics and Astronautics, 2019, 45(3):538-545. [9] Bucki N, Mueller M W. Design and control of a passively morphing quadcopter[C]//IEEE International Conference on Robotics and Automation. Piscataway, USA:IEEE, 2019:9116-9122. [10] Falanga D, Kleber K, Mintchev S, et al. The foldable drone:A morphing quadrotor that can squeeze and fly[J]. IEEE Robotics and Automation Letters, 2019, 4(2):209-216. [11] Bai Y, Gururajan S. Evaluation of a baseline controller for autonomous "figure-8" flights of a morphing geometry quadcopter:Flight performance[J]. Drones, 2019, 3(3). DOI:10. 3390/drones3030070. [12] Zhao M J, Kawasaki K, Okada K, et al. Transformable multirotor with two-dimensional multilinks:Modeling, control, and motion planning for aerial transformation[J]. Advanced Robotics, 2016, 30(13):825-845. [13] 陶广宏,房立金,徐鑫霖,等.多节链式移动机器人单元模块研究与设计[J].机器人, 2018, 40(6):887-893,902. Tao G H, Fang L J, Xu X L, et al. Research and design of the unit module of the multi-link mobile robot[J]. Robot, 2018, 40(6):887-893,902. [14] 刘金国,王越超,李斌,等.链式可重构模块化机器人变形机理与实现[J].农业机械学报, 2005, 36(9):101-105. Liu J G, Wang Y C, Li B, et al. Transmutation mechanisms and its realization of a chain-type reconfigurable modular robot[J]. Transactions of the Chinese Society for Agricultural Machinery, 2005, 36(9):101-105. [15] 王明辉,马书根,李斌,等.异构模块型可变形机器人狭窄空间转向性能研究[J].机器人, 2015, 37(2):161-167. Wang M H, Ma S G, Li B, et al. Steering for a transformable robot with heterogeneous modules in narrow space[J]. Robot, 2015, 37(2):161-167. [16] 姚美宝.空间模块化机器人构型重组与控制方法研究[D]. 哈尔滨:哈尔滨工业大学, 2019. Yao M B. Research on reconfiguration and control technologies of modular robots in space applications[D]. Harbin:Harbin Institute of Technology, 2019. [17] 张旭,郑泽龙,齐勇. 6自由度串联机器人D-H模型参数辨识及标定[J].机器人, 2016, 38(3):360-370. Zhang X, Zheng Z L, Qi Y. Parameter identification and calibration of D-H model for 6-DOF serial robots[J]. Robot, 2016, 38(3):360-370. [18] Zhou M J, Kawasaki K, Chen X Y, et al. Whole-body aerial manipulation by transformable multirotor with two-dimensional multilinks[C]//IEEE International Conference on Robotics and Automation. Piscataway, USA:IEEE, 2017:5175-5182. [19] 卢艳军,张晓东,纪鹏飞,等.多旋翼飞行器螺旋桨升力特性测试实验系统[J].实验室研究与探索, 2017, 36(1):69-72,79. Lu Y J, Zhang X D, Ji P F, et al. Experimental system for the propeller thrust characteristics of multi-rotor aircraft[J]. Research and Exploration in Laboratory, 2017, 36(1):69-72,79.
