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trajectory optimization of aerial slung load release for piloted helicopters

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Chinese Journal of Aeronautics 2021年第2期34卷 229-239页

作者： Luofeng WANG Renliang CHEN Xufei YAN National Key Laboratory of Science and Technology on Rotorcraft Aeromechanics Nanjing University of Aeronautics and AstronauticsNanjing 210016China

This study aims to provide the pilot with optimal control time histories for stabilization of a helicopter after releasing the slung load in aerial delivery missions. A model with 21 degrees of freedom(21-DOF) has been developed and validated for a helicopter slung load system. The control history is generated with detailed procedure based on trajectory optimization. Effects of the objective function formulation on the results are discussed and rules are obtained to assist in the objective function determination. We conclude that the pilot should first decrease and then increase the collective control and adjust the longitudinal control to stabilize the helicopter after the in-hover slung load release. The obtained control history is reasonable and helpful for safety and efficiency improvement. Effects of path constraints and the Flight Control System(FCS) are studied. More stringent path constraints will lead to longer time spent and more controls. Stronger stiffness and weaker damping from the FCS will cause milder control histories but sharper on-axis state histories.

关键词： Helicopter slung load systems Nonlinear equations Optimal control Pilot inputs Slung load release trajectory optimization

trajectory optimization and Power Allocation Scheme Based on DRL in Energy Efficient UAV-Aided Communication Networks

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Chinese Journal of Electronics 2022年第3期31卷 397-407页

作者： WANG Chaowei CUI Yuling DENG Danhao WANG Weidong JIANG Fan School of Electronic Engineering Beijing University of Posts and Telecommunications Key Laboratory of Universal Wireless Communications Ministry of Education School of Telecommunications and Information Engineering Xi'an University of Posts and Telecommunications

With flexibility, convenience and mobility, unmanned aerial vehicles(UAVS) can provide wireless communication networks with lower costs, easier deployment, higher network scalability and larger *** paper proposes the deep deterministic policy gradient algorithm to jointly optimize the power allocation and flight trajectory of UAV with constrained effective energy to maximize the downlink throughput to ground users. To validate the proposed algorithm, we compare with the random algorithm, Q-learning algorithm and deep Q network algorithm. The simulation results show that the proposed algorithm can effectively improve the communication quality and significantly extend the service time of UAV. In addition, the downlink throughput increases with the number of ground users.

关键词： unmanned aerial vehicles remotely operated vehicles trajectory optimization Q-learning algorithm power allocation scheme flight trajectory communication quality optimisation mobile robots random algorithm deep Q network algorithm learning systems constrained effective energy ground users autonomous aerial vehicles network scalability resource allocation UAVS energy efficient UAV-aided communication networks gradient methods deep deterministic policy gradient algorithm trajectory control radio networks wireless communication networks

trajectory optimization for the Horyu-VI international lunar mission

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Astrodynamics 2021年第3期5卷 263-278页

作者： Federico De Grossi Paolo Marzioli Mengu Cho Fabio Santoni Christian Circi Sapienza University of Rome 00138 RomeItaly Kyushu Institute of Technology Kitakyushu 804-8550Japan

The Horyu-VI nano-satellite is an international lunar mission with the purpose of studying the lunar horizon glow(LHG)—a still unclear phenomenon caused by electrostatically charged lunar dust *** study analyzes the mission trajectory with the hypothesis that it is launched as a secondary payload of the NASA ARTEMIS-II *** particular,the effect of the solar gravity gradient is studied;in fact,depending on the starting relative position of the Moon,the Earth,and the Sun,the solar gradient acts differently on the trajectory—changing it ***,the transfer and lunar capture problem is solved in several cases with the initial Sun–Earth–Moon angle as the key ***,the inclination with respect to the Moon at capture is constrained to be ***,the problem of stabilization and circularization of the lunar orbit is addressed in a specific case,providing an estimate of the total propellant cost to reach the final orbit around the Moon.

关键词： trajectory optimization Artemis mission lunar mission lunar horizon glow(LHG) weak stability boundary

trajectory optimization Design for Morphing Wing Missile

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Journal of Harbin Institute of Technology(New Series) 2015年第5期22卷 25-30页

作者： Ruisheng Sun Chao Ming Chuanjie Sun Nanjing University of Science and Technology Institute of Systems Engineering China Academy of Engineering Physics

This paper presents a new particle swarm optimization( PSO) algorithm to optimize the trajectory of morphing-wing missile so as to achieve the enlargement of the maximum range. Equations of motion for the twodimensional dynamics are derived by treating the missile as an ideal controllable mass point. An investigation of aerodynamic characteristics of morphing-wing missile with varying geometries is performed. After deducing the optimizing trajectory model for maximizing range,a type of discrete method is put forward for taking optimization control problem into nonlinear dynamic programming problem. The optimal trajectory is solved by using PSO algorithm and penalty function method. The simulation results suggest that morphing-wing missile has the larger range than the fixed-shape missile when launched at supersonic speed,while morphing-wing missile has no obvious range increment than the fixed-shape missile at subsonic speed.

关键词： morphing wing missile trajectory optimization optimization model particle swarm optimization(PSO)

trajectory optimization of a reentry vehicle based on artificial emotion memory optimization

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Journal of Systems Engineering and Electronics 2021年第3期32卷 668-680页

作者： FU Shengnan WANG Liang XIA Qunli School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China Beijing Aerospace Automatic Control Institute Beijing 100854China School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China

The trajectory optimization of an unpowered reentry vehicle via artificial emotion memory optimization(AEMO)is ***,reentry dynamics are established based on multiple constraints and parameterized control variables with finite dimensions are *** the constraint is not satisfied,a distance measure and an adaptive penalty function are used to address this ***,AEMO is introduced to solve the trajectory optimization *** on the theories of biology and cognition,the trial solutions based on emotional memory are *** search strategies are designed for realizing the random search of trial solutions and for avoiding becoming trapped in a local *** states of the trial solutions are determined according to the rules of memory enhancement and *** the iterations proceed,the trial solutions with poor quality will gradually be ***,the number of trial solutions is decreased,and the convergence of the algorithm is ***,a numerical simulation is conducted,and the results demonstrate that the path and terminal constraints are satisfied and the method can realize satisfactory performance.

关键词： trajectory optimization adaptive penalty function artificial emotion memory optimization(AEMO) multiple constraint

trajectory optimization for 7-Dofs Space Manipulator

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Journal of Beijing Institute of Technology 2017年第2期26卷 143-149页

作者： Wencheng Ni Zhihong Jiang Hui Li Bo Wei Xiaoyun Li Bainan Zhang Qiang Huang School of Mechatronical Engineering Beijing Institute of Technology Beijing 100081 China China Academy of Space Technology Beijing 100094 China

The space manipulator is always designed to have 7 degrees of freedom（Dofs）with the consideration of energy limitation,as well as the flexible moving ***,how to plan the trajectory is important to improve the performance of the *** this paper,the speed of the end effector is configured as a projecting parameter,when a constant acceleration is applied to adjust the *** implement this trajectory planning strategy,an optimization algorithm through the pseudo inverse of Jacobin matrix is designed,which adjusts the weight functions of *** to the functional theory,this algorithm is analyzed and the optimal solution is found in numerous sets of planning.A MATLAB simulation platform is established and the results verity the effectiveness of the algorithm.

关键词： redundant degree of freedom space manipulator trajectory optimization

trajectory optimization for a cleaning robot for a hotline insulator

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Journal of Harbin Institute of Technology(New Series) 2005年第6期12卷 696-699页

作者：孙斌徐威杨汝清 Research Institute of Robotics Shanghai Jiaotong University Shanghai 200030 China

We investigated the vibration of a cleaning robot for hotline insulators, providing a flexible elevating link with a rigid moving link at the end. A Lagrange dynamic model is established based on the assumed mode method. An approach is proposed to reduce residual vibration of the flexible elevating link by optimizing acceleration of rigid link using the Pontryagin maximum principle (PMP). A numerical solution to the proposed optimization problem including a two-point boundary-value problem (2PBVP) is developed. Residual vibration of the flexible elevating link of the optimal acceleration profile is compared with that of the optimal trapezoid velocity profile. The result shows that the proposed trajectory optimization method can reduce the residual vibration more effectively.

关键词： hotline robot flexible manipulator dynamic modeling trajectory optimization

trajectory optimization and Motion Simulation of a Flexible Polishing Industrial Robot for Watchcases

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Journal of Donghua University(English Edition) 2021年第2期38卷 129-139页

作者： YANG Jingjing JIN Xiaoyi XIE Tengxiao XI Ying School of Mechanical and Automotive Engineering Shanghai University of Engineering ScienceShanghai 201620China College of Mechanical Engineering Tongji UniversityShanghai 201802China

To optimize the working time of the flexible polishing industrial robot for watchcases,the polishing efficiency should be *** on the quintic B-spline fitting curve trajectory planning method associated with the optimal time interval and the trajectory point angle,the trajectory route of the flexible polishing industrial robot for case parts was optimized by the Matlab *** operation time of the flexible polishing industrial robot could reach the optimal *** joints of the robot can be cooperated with each other to ensure that the motion track of the end-effector of the robot arm is closer to the expected motion *** on the Adams software,the obtained trajectory curve of multi-objective optimization was simulated,which verified the trajectory fitted after multi-objective *** angular acceleration and angular plus acceleration curves were *** guidance was carried out for the subsequent experiment by Matlab and Adams simulation analysis.

关键词： trajectory optimization multi-objective optimization Matlab software Adams software industrial robot

trajectory optimization for Terminal Phase Flight of Hypersonic Reentry Vehicles with Multi-constraints

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Trajectory Optimization for Terminal Phase Flight of Hyperso...