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Acta Mechanica Sinica 2024年第2期40卷 259-267页

作者：崔嵬刘伟崔一南 Navigation and Control Technology Research Institute of China North Industries Group Corporation Limited Beijing100089China School of Materials Science and Engineering Tsinghua UniversityBeijing100084China Applied Mechanics Lab. School of Aerospace EngineeringTsinghua UniversityBeijing100084China

纳米尺寸的辐照缺陷常常会在位错线附近聚集,形成装饰效应.研究者通常采用级联诱导源硬化模型描述装饰效应引起的辐照硬化.本研究工作发现不可动辐照缺陷装饰位错会导致辐照硬化,硬化程度与理论模型预测一致.然而,当装饰辐照缺陷可动时... 详细信息

纳米尺寸的辐照缺陷常常会在位错线附近聚集,形成装饰效应.研究者通常采用级联诱导源硬化模型描述装饰效应引起的辐照硬化.本研究工作发现不可动辐照缺陷装饰位错会导致辐照硬化,硬化程度与理论模型预测一致.然而,当装饰辐照缺陷可动时,则不发生辐照硬化,甚至发生软化,这种硬化消失是由于位错环始终处于与位错线相互作用力近似为零的区域,并与位错线发生关联运动.该工作带来了对辐照缺陷装饰效应和辐照硬化的新理解.

关键词：相互作用力辐照硬化辐照缺陷装饰效应硬化模型位错环纳米尺寸模型预测

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Collision Probability Sliding Mode Guidance for Spacecraft Autonomous Obstacle Avoidance

SSRN

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SSRN 2024年

作者： Yang, He Long, Jiateng Liang, Zixuan Xu, Rui Zhu, Shengying Institute of Deep Space Exploration Beijing Institute of Technology Beijing10081 China Key Laboratory of Autonomous Navigation and Control for Deep Space Exploration Ministry of Industry and Information Technology Beijing100081 China

Spacecraft must possess the capability of autonomous obstacle avoidance to ensure flight safety. Currently, the available methods for obstacle avoidance guidance are primarily deterministic and will fail with large state estimation errors, which necessitates the robustness of guidance algorithms towards uncertainties. A collision probability sliding mode guidance method is presented for the autonomous obstacle avoidance of spacecraft. Based on the multiple sliding surfaces guidance law, a sliding mode structure is proposed to realize obstacle avoidance in the presence of state uncertainty, taking into account the collision probability constraint. First, A multiple power reaching law is designed to enhance the convergence speed of the first sliding surface, so that the spacecraft system reaches the target state within a finite time. Subsequently, the collision probability gradient information function is defined according to the relative relation between the spacecraft and obstacles. This function is then combined with the improved reaching law to develop the second sliding surface. The sliding surface can quantify the collision probability in real-time, and generate corresponding obstacle avoidance guidance commands to prompt the spacecraft to move away from the obstacles according to the magnitude of collision probability, which is robust to the state uncertainty. The capability of the proposed guidance algorithm is validated by a series of simulations, including scenarios involving asteroid landing and spacecraft rendezvous, and the effectiveness and robustness in the face of uncertainties are confirmed. © 2024, The Authors. All rights reserved.

关键词： Space rendezvous

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ACCELERATED PERFORMANCE DEGRADATION TEST AND ANALYSIS OF HIGH-TEMPERATURE STRAIN GAUGES 13

ACCELERATED PERFORMANCE DEGRADATION TEST AND ANALYSIS OF HIG...

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13th International Conference on Quality, Reliability, Risk, Maintenance, and Safety Engineering, QR2MSE 2023

作者： Li, Lu Wang, Zhihua Yang, Ning Wu, Qiong Wang, Hanyue Mao, Zelong Ren, Kunpeng Wang, Qiuyue Wang, Yifeng National Key Laboratory of Strength and Structural Integrity School of Aeronautic Science and Engineering Beihang University Beijing China Shenyang Aircraft Design and Research Institute Shenyang China Institute of Spacecraft System Engineering China Academy of Space Technology Beijing China Navigation Instrument Research Institute Tianjin China Beijing Institute of Control Engineering Beijing China

ISBN: (纸本)9781839539848

With the extension of the service time of the structure and the worse service temperature conditions, the drift problem of high-temperature strain gauges gradually becomes prominent. This research aims to address the issue of the drift of measurement results because of the performance degradation of high-temperature strain gauges, and investigate the drift law under different temperatures considering complex service environments. In this paper, a combination of experimental research and theoretical analysis is utilized to design and conduct the accelerated performance degradation test on high-temperature strain gauges. Based on the result of the test, an accelerated performance degradation model is developed using the Wiener process and Arrhenius model. Finally, estimation curves for the average value and percentile value of the performance parameters of the high-temperature strain gauges are obtained, which demonstrates that the established accelerated performance degradation model can reasonably describe the degradation law. Additionally, the established accelerated performance degradation model enables effective analysis and compensation of gauge drift at any temperature. © The Institution of Engineering & technology 2023.

关键词： Strain gages

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Terminal Impact-angle-constrained Guidance Law of Miniature Munition Based on High-order Fully Actuated System Approach

Terminal Impact-angle-constrained Guidance Law of Miniature ...

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2022 Chinese Automation Congress, CAC 2022

作者： Chen, Shiwei Fan, Junfang Wang, Wei Ji, Yi Liu, Ning Beijing Institute of Technology School of Aerospace Engineering Beijing100081 China Beijing Institute of Technology Beijing Key Laboratory of UAV Autonomous Control Beijing100081 China Beijing Information Science & Technology University Beijing Key Laboratory of High Dynamic Navigation Technology Beijing100192 China

ISBN: (纸本)9781665465335

Aiming at the terminal impact-angle constraint in the interception of large maneuvering targets by munition, this paper proposes a three-dimensional(3D) maneuvering target interception guidance law combined with the high-order fully-actuated (HOFA) system theory based on biased proportional navigation guidance (BPNG). First, a complete second-order nonlinear model with fully-actuation is built for munition-target relative motion without the small-angle assumption. Second, the nonlinear system of the munition-target relative motion is transformed into a quasi-feedback system, and a HOFA model is developed for the system. A BPNG law with the linear relationship of the line-of-sight angle is introduced to transform the closed-loop system into a linear time-invariant closed-loop system with the expected characteristic structure. Finally, target maneuver information is taken as the model compensation and adopted as the external input of the closed-loop system together with the remainder of the guidance law;thus, the channel coupling of the nonlinear three-dimensional system is eliminated. The effectiveness of the proposed method is verified by simulation results. © 2022 IEEE.

关键词： Closed loop systems

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Hierarchical reinforcement learning based planning method with uncertainty in limited visions for lunar rovers 74

Hierarchical reinforcement learning based planning method wi...

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74th International Astronautical Congress, IAC 2023

作者： Lu, Siyao Xu, Rui Yu, Dengyun Li, Zhaoyu Gao, Ai Wang, Bang Pan, Bo School of Aerospace Engineering Beijing Institute of Technology 5th Zhongguancun South Street Haidian Distinct Beijing100081 China Key Laboratory of Autonomous Navigation and Control for Deep Space Exploration Beijing Institute of Technology Ministry of Industry and Information Technology Beijing100081 China China Aerospace Science and Technology Corporation 16th Fucheng Road Haidian Distinct Beijing100049 China Beijing Institute of Spacecraft Engineering Beijing Beijing100094 China

China and Russia will establish the International Lunar Research Station together in around 2035 when the resource acquisition from the lunar surface and the construction of lunar bases will be applied at the beginning period. However, the accuracy of the lunar surface digital elevation map (DEM) is not enough, which cannot meet the needs of path planning or acting for lunar rovers. What's more, there are limitations to the vision of each rover compared to the wide moon surface, so rovers are required to foresee the obstacles and adjust movements for obstacle avoidance, power saving, and safety. Another problem is that the acquisition and construction are long-term tasks so pure path planning methods won't work properly. Therefore, we propose a new way of planning both the path and the task by hierarchical reinforcement learning, where hundreds of simulation environments in which the obstacles and places for acquisition, charging, blending, and construction are varied. Rovers can only obtain a vision of several meters and they will only know the approximate locations of targets. So uncertainty occurs during the rovers' way to the targets, on which there are small and large obstacles. Targets will be given by the task level from which the guidance will be applied on the path level. However, data on the task level generated by the hierarchical environment is not enough for training the task policies so pre-generated data will be prepared for the pre-training of the task policies then the policies will be set on the task level with constraints while updating rather than joint training from the beginning. In our experiment, we intend that our way leads each rover to finish the long-term tasks without meeting large obstacles, trains the whole hierarchal policy more quickly than the traditional way, and generates a better result than pure path planning in the uncertainty environment for long-term tasks. Copyright © 2023 by the International Astronautical Federation (IAF).

关键词： hierarchical reinforcement learning lunar rover uncertainty

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GGIMN: Gravity Gradient Image Matching Network with Adaptive Adjoint Smoothing for AUV navigation

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IEEE Transactions on Vehicular technology 2025年

作者： Li, Tianjiao Wang, Bo Song, Bao Deng, Zhihong Fu, Mengyin Beijing Institute of Technology School of Automation Beijing100081 China Tianjin University of Technology School of Electrical Engineering and Automation Tianjin300382 China Beijing Institute of Technology Engineering Research Center of the Ministry of Education for Navigation Guidance and Control Technology School of Automation Beijing100081 China Nanjing University of Science and Technology Nanjing210014 China

Gravity gradient-aided navigation is a promising navigation method for autonomous underwater vehicle (AUV), in which matching algorithm is its key technology. Image matching algorithms have higher matching accuracy and information utilization than single point matching and sequence matching. However, the spatial domain image feature matching ability is weak in areas with insignificant feature changes due to the uneven feature distribution in the gravity gradient reference map. To break through this limitation and solve the problem of insufficient spatial domain image feature matching ability, we propose a gravity gradient image matching network (GGIMN) with adaptive adjoint smoothing for AUV navigation and positioning. First, a training set for GGIMN with equal numbers of positive and negative samples is constructed by preparing the gravity gradient reference map and fitting the gravity gradient measured map. Then, the feature extraction part of MatchNet is expanded to construct a deep learning network with five gravity gradient twin towers in parallel. Subsequently, an adaptive adjoint smoothing method that combines the idea of sequence matching is proposed to solve the problem of unsmooth matching trajectory and further improve the matching accuracy. Finally, the GGIMN is trained offline, and the gravity gradient map is matched and positioned online. The results of marine experiments show that the GGIMN has higher matching and positioning accuracy, and the average positioning error is reduced beyond 70% compared with onedimensional matching algorithms such as single-point iteration and sequence matching. © 1967-2012 IEEE.

关键词： Image matching

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Highly constrained cooperative guidance for flexible landing on asteroids

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Chinese Journal of Aeronautics 2025年第4期 353-364页

作者： Chang LYU Zixuan LIANG Shengying ZHU School of Aerospace Engineering Beijing Institute of Technology Key Laboratory of Autonomous Navigation and Control for Deep Space Exploration (Beijing Institute of Technology) Ministry of Industry and Information Technology

Flexible lander, composed of multiple nodes connected by flexible material, can reducethe bouncing and overturning during the asteroid landing. To satisfy the complex constraints inthe node cooperation of the flexible landing, an intelligent cooperative guidance method is pro-posed. The method consists of a double-layer cooperative guidance structure, a guidance parameterdetermination approach, and an action priority strategy. The double-layer contains a basic guid-ance used to satisfy the terminal state constraints, and a compensatory guidance used to satisfythe lander's attitude constraint. For the compensatory guidance, the parameters are determinedby multi-agent system, which are trained according to the performance index of flexible landing tra-jectories. The action priority strategy is used to reduce the detrimental effect of parameter inconsis-tency on the node cooperation. The simulation of flexible landing shows that the cooperativeguidance method is effective in improving the landing accuracy while satisfying the ***, the method is robust to the disturbance in the navigation and control.

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Reliability-Based Dynamic Positioning control for Turret-Moored Vessels with Prescribed Performance 1

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Chinese Intelligent Automation Conference, CIAC 2023

作者： Tuo, Yulong Feng, Guilin Liang, Xiao Wang, Shasha Guo, Chen College of Marine Electrical Engineering Dalian Maritime University Dalian116026 China Dalian Key Laboratory of Swarm Control and Electrical Technology for Intelligent Ships Dalian116026 China Qingdao Special Equipment Inspection Research Institute Qingdao266100 China TianJin Navigation Instruments Research Institute Tianjin300130 China

ISBN: (数字)9789819961870

ISBN: (纸本)9789819961863

To consider the safety of mooring lines and transient performance of system, a reliability-based dynamic surface controller with prescribed performance is proposed for the dynamic positioning (DP) system of turret-moored vessels. The descriptions are given for the vessel model and the reliability of mooring lines at first. Then, a dynamic surface controller is presented on the basis of reliability of mooring lines and prescribed performance function. The performance specifications are imposed in advance on the reliability and heading tracking errors according to the actual demands. By adjusting the reliability, the ability of mooring system can be fully used within the safe range of mooring lines. Therefore, less energy consumption is needed for the DP system. Finally, the numerical simulations illustrate the performance of the presented DP controller. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd 2023.

关键词： Reliability

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Human Following Robot Based on Object Detection for Aerospace Application 1

Human Following Robot Based on Object Detection for Aerospac...

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1st International Conference of Adisutjipto on Aerospace Electrical Engineering and Informatics, ICAAEEI 2024

作者： Sumari, Arwin Datumava Wahvudi Aryandika, Ahnaf Bagus Purnami, Ndaru Atmi Dermawan, Denny Syamsiana, Ika Noer State Polytechnic of Malang Cognitive Artificial Intelligence Research Group Department of Electrical Engineering Malang Indonesia Adisutjipto Institute of Aerospace Technology Electrical Engineering Study Program Yogyakarta Indonesia Adisutjipto Institute of Aerospace Technology Aerospace Navigation Instrumentation Control Automation and Robotics System Research Group Electrical Engineering Study Program Yogyakarta Indonesia Adisutjipto Institute of Aerospace Technology Electrical Engineering Study Program Aerosp. Digit. Syst. Microprocessor Microcontroller and Programmable Logic Devices Research Group Yogyakarta Indonesia

ISBN: (纸本)9798331507930

In this research, the Human Following Robot (HFR) prototype has been designed and implemented using YOLO v3-Tiny and Tensor Flow Lite on Raspberry Pi hardware named Rewang. The HFR Rewang is designed to assist aircraft technicians by bringing maintenance tool kits to aircraft shelters. Rewang's movement is based on a camera as a vision sensor following the movement of human entities. Image input is processed by YOLO v3-Tiny through the determination of the bounding box, the calculation of Euclidean Distance, and the determination of the pixel value of the camera as the basis of Rewang's movement which is regulated by an L298N driver motor that controls two Direct Current (DC) motors for the left and right wheels. The test results show that Rewang can move at an average speed of 0.18 m/s at 2 m with a travel time of 11 seconds with a light intensity of more than 250 lux. The minimum and maximum distance of object detection is as far as 120 cm and 400 cm, with an object detection accuracy of 95.8%. Rewang allows the HFR to have a larger carrying capacity to bring more complete aircraft maintenance tools and is prospective for other aerospace and general applications. © 2024 IEEE.

关键词： Travel time

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Constrained Trajectory Optimization for Coordinated Maneuver Planning of Spacecraft with Dual Manipulators

SSRN

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SSRN 2025年

作者： Zhu, Zhe Xu, Rui Li, Zhaoyu Zhu, Shengying Long, Jiateng Zhang, Shengyu Institute of Deep Space Exploration Technology Beijing Institute of Technology Beijing100081 China Key Laboratory of Autonomous Navigation and Control for Deep Space Exploration Beijing Institute of Technology Ministry of Industry and Information Technology Beijing100081 China Innovation Academy for Microsatellites of Chinese Academy of Sciences Shanghai201203 China

Application of spacecraft with movable mechanisms is more effective in attitude maneuver missions than rigid three-axis spacecraft owning to extra degrees of freedom, but also raises challenges on attitude trajectory planning. This paper investigates the application of a hierarchical mixed-strategy optimization method to coordinated attitude trajectory planning of the spacecraft with dual manipulators. In order to overcome the computation complexity issue, decoupled strategy is employed to split demanded pointing into the body quaternion and manipulator joint angles. Having the pointing path compliant with pointing constraints, objectives of energy consumption and joint angle change are designed. The secondary rotation of quaternion sequence is utilized as design variables in conjunction with a hierarchical swarm optimization algorithm using mixed search strategy for attitude trajectory optimization. The optimal solutions of body attitude and joint angle path are parametrized with cubic splines to solve complete trajectories of system states using inverse dynamics while imposed constraints are satisfied. Simulation results are presented for coordinated attitude trajectory planning of spacecraft with two manipulators and demonstrate the effectiveness of the proposed optimization method. © 2025, The Authors. All rights reserved.

关键词： Particle swarm optimization (PSO)

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