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arXiv 2021年

作者： Zhang, Yunhao Sha, Zhendong Su, Guangyuan Zhou, Hao Yang, Jiangzhong Jiang, Peng Liu, Yongquan Li, Bing Wang, Tiejun State Key Laboratory for Strength and Vibration of Mechanical Structures School of Aerospace Engineering Xi’an Jiaotong University Xi’an710049 China Beijing Key Laboratory of Intelligent Space Robotic Systems Technology and Applications Beijing Institute of Spacecraft System Engineering China Academy of Space Technology Beijing100094 China School of Aeronautics Northwestern Polytechnical University Shaanxi Xi'an710072 China

Wave steering by artificial materials (for example, phononic crystals and acoustic metamaterials) is a fascinating frontier in modern physics and engineering, but suffers from bulky sizes and intractable challenges in fabrication. Here, a sparse layer of identical tiny scatters, which we call meta-fences, is presented with a non-destructive way to omnidirectionally block flexural waves in plates. The underlying mechanism is that the restraining force and moment of the scatter are tuned simultaneously to counter-balance the incident wave. Both our experimental results and numerical analysis have demonstrated that broadband wave sources ranging from 3 to 7 kHz can be segregated from the protected area by the meta-fence. In addition, the meta-fence is further assembled into a waveguide routing with an arbitrary configuration. Compared with previous isolators and waveguides, our meta-fences exhibit absolute advantages in compact size, flexible configuration, and high structural strength. The current scenario sheds light on the design of lightweight-and-strong architectures for vibration control and energy harvesting with a high efficiency, and can be extended to microfluidics, acoustics, seismology and other fields. Copyright © 2021, The Authors. All rights reserved.

关键词： Energy harvesting

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Efficient Random Subspace Decision Forests with A Simple Probability Dimensionality Setting Scheme

SSRN

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SSRN 2022年

作者： Wang, Quan Wang, Fei Li, Zhongheng Jiang, Peilin Ren, Fuji Nie, Feiping Institute of Artificial Intelligence and Robotics Xi’an Jiaotong University Shaanxi Xi’an710049 China Beijing Key Laboratory of Intelligent Space Robotic Systems Technology and Applications Beijing Institute of Spacecraft System Engineering Beijing100094 China School of Software Engineering Xi’an Jiaotong University Shaanxi Xi’an710049 China School of Computer Science and Engineering University of Electronic Science and Technology of China Sichuan Chengdu611731 China Northwestern Polytechnical University Shaanxi Xi’an710072 China

The random subspace concept is widely used in decision forests. However, there is not a reasonable approach to specify the appropriate number of randomly selected features. Previous random subspace decision forests simply specify the random subspace dimensionality d s to a preset function value such as [log 2 d ] or [√ d ] where d is the number of the total feature dimensions. Actually, this preset value may be a relatively poor choice for high dimensional data sets. In this paper, a novel framework named Efficient Random Subspace decision forest (ERS) is proposed which pays attention to how to set the random subspace dimensionality for each decision tree of decision forests. Specifically, a simple discrete uniform distribution is employed to set with probability the number of randomly selected features for each tree in random subspace decision forests. The proposed Half Range Discrete Uniform distribution-based Varied Dimensionality setting (HRDUVD) method removes the hesitation of how to preset an appropriate d s for different data sets but also results in good enough classification performance along with relatively short running time. Plenty of experiments on public benchmark data sets have demonstrated the effectiveness and the efficiency of the proposed ERS. © 2022, The Authors. All rights reserved.

关键词： Decision trees

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Improved deep deterministic policy gradient algorithm based on prioritized sampling

Improved deep deterministic policy gradient algorithm based ...

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Chinese intelligent systems Conference, CISC 2018

作者： Zhang, HaoYu Xiong, Kai Bai, Jie Science and Technology on Space Intelligent Control Laboratory Beijing Institute of Control Engineering Beijing100190 China Beijing Key Laboratory of Intelligent Space Robotic Systems Technology and Applications Beijing Institute of Spacecraft System Engineering Beijing China

ISBN: (纸本)9789811322877

Deep reinforcement learning tends to have low sampling efficiency, and prioritized sampling algorithm can improve the sampling efficiency to a certain extent. The prioritized sampling algorithm can be used in deep deterministic policy gradient algorithm, and a small sample sorting method is proposed to solve the problem of high complexity of the common prioritized sampling algorithm. Simulation experiments prove that the improved deep deterministic policy gradient algorithm improves the sampling efficiency and the training performance is better. © Springer Nature Singapore Pte Ltd. 2019.

关键词： Reinforcement learning

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Globally optimal consensus maximization for robust visual inertial localization in point and line map

arXiv

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arXiv 2020年

作者： Jiao, Yanmei Wang, Yue Fu, Bo Tan, Qimeng Chen, Lei Wang, Minhang Huang, Shoudong Xiong, Rong State Key Laboratory of Industrial Control and Technology Zhejiang University Hangzhou China Beijing Key Laboratory of Intelligent Space Robotic System Technology and Applications Beijing Institute of Spacecraft System Engineering Beijing China Application Lab Huawei Incorporated Company China University of Technology Sydney Australia

Map based visual inertial localization is a crucial step to reduce the drift in state estimation of mobile robots. The underlying problem for localization is to estimate the pose from a set of 3D-2D feature correspondences, of which the main challenge is the presence of outliers, especially in changing environment. In this paper, we propose a robust solution based on efficient global optimization of the consensus maximization problem, which is insensitive to high percentage of outliers. We first introduce translation invariant measurements (TIMs) for both points and lines to decouple the consensus maximization problem into rotation and translation subproblems, allowing for a two-stage solver with reduced search space. Then we show that (i) the rotation can be estimated by minimizing TIMs using only 1-dimensional branch-and-bound (BnB), (ii) the translation can be estimated by running 1-dimensional search for each of the three axes with prioritized progressive voting. Compared with the popular randomized solver, our solver achieves deterministic global convergence without requiring an initial value. Furthermore, ours is exponentially faster compared with existing BnB based methods. Finally, our experiments on both simulation and real-world datasets demonstrate that the proposed method gives accurate pose estimation even in the presence of 90% outliers (only 2 inliers). Copyright © 2020, The Authors. All rights reserved.

关键词： Statistics

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A Survey of space robotic Technologies for On-Orbit Assembly

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空间科学与技术（英文） 2023年第3期3卷 291-303页

作者： Delun Li Lou Zhong Wei Zhu Zhipeng Xu Qirong Tang Wenhao Zhan Beijing Key Laboratory of Intelligent Space Robotic Systems Technology and Applications Beijing Institute of Spacecraft System EngineeringCASTBeijingChina College of Mechanical Engineering Tongji UniversityShanghaiChina National Key Laboratory of Human Factors Engineering China Astronaut Research and Training CenterBeijingChina

The construction of large structures is one of the main development trends of the space exploration in the future,such as large space stations,large space solar power stations,and large space *** is one of important development tendency,which aims to make full use of space robots to assemble space structures autonomously in the aerospace *** that on-orbit assembly is an effective method to solve the problem of construction of large-scale spatial structures,it is necessary to motivate and facilitate the research of space robotics technologies for on-orbit ***,in this paper,the development status of space robot technology and the relevant space robot on-orbit assembly technology in recent decades are ***,based on the space robot motion planning and assembly sequence planning,the development of space robot planning algorithms is *** space robot assembly task,the space robot assembly method is *** the control point of view,how to solve the vibration suppression and compliant assembly of on-orbit assembly is reviewed,which provides a reference for the autonomous intelligent assembly of space robots for large-scale structures in *** order to simulate the space assembly scene on the ground,this paper introduces the development of ground verification experiments and provides ideas for the effective verification of space on-orbit assembly *** summary,though some of these problems have been satisfactorily solved in the past research,further research is still necessary in the ***,it looks forward to the future research direction of space machine on-orbit assembly.

关键词： technologies space assembly on-orbit robotic survey

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Study on Buffering and Motion Control of Quadruped Explorer

Study on Buffering and Motion Control of Quadruped Explorer

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IEEE Advanced Information technology, Electronic and Automation Control Conference (IAEAC)

作者： Pei Zhang Xiangyu Gao Qingqing Wei Chu Wang Xin Liu Beijing Key Laboratory of Intelligent Space Robotic System Technology and Application Beijing China

To address the problem of insufficient driving capacity of wheel explorer in rugged terrain, a quadruped explorer with 12 DOF was proposed. The dynamic model of quadruped explorer was established in gazebo, the integrated method of buffering and motion control was verified through simulation which showed that the landing impact upon explorer landing leg was significantly reduced and the explorer gait motion was both stable and flexible.

关键词： Jacobian matrices Information technology Automation Conferences Wheels Dynamics Motion control

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key Techniques on Unified Identity Authentication in OpenMBEE Integration

Key Techniques on Unified Identity Authentication in OpenMBE...

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IEEE International Conference on Electronics and Communication Engineering (ICECE)

作者： Junjie Xue Junhua Zhou Guoqiang Shi Chaoqun Feng Penghua Liu Hongyan Quan Beijing Complex Product Advanced Manufacturing Engineering Research Center Beijing Simulation Center Beijing China State Key Laboratory of Intelligent Manufacturing System Technology Beijing Institute of Electronic System Engineering Beijing China Beijing Simulation Center Science and Technology on Space System Simulation Laboratory Beijing China School of Computer Science and Technology East China Normal University Shanghai China

ISBN: (纸本)9781728188577

In order to make full use of the concept of model-based systems engineering (MBSE) and the collaborative design capability of the open model-based engineering environment (OpenMBEE) in establishing complex product development platform, we propose an effective method to solve the problem of unified identity authentication in OpenMBEE integration. The proposed method is based on the Model View Controller(MVC) architecture in OpenMBEE, which has the characteristics strong plasticity and can be benefit for expanding the function in the controller layer. In our research, we make full use of the Software Development Kit (SDK) of OpenMBEE to expand the existing functions in the controller layer, and increase the function of communicating with the application development platform, then realize the function of sharing user authentication information between the development platform and OpenMBEE. After expansion, the system includes three modules, including the Front-end Service Module(FSM), MQ based Information Receiving Service Module(IFRSM), and the OpenMBEE Backend Server Module(BSM). The effectiveness of the proposed strategies is verified by some practical instances, which verifies that our study can provide an effective design idea for the identity authentication in OpenMBEE integration.

关键词： Analytical models Databases Authentication Computer architecture Control systems Data models Software

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Trajectory Planning Simulation of 3-DoF Parallel Wrist Mechanisms Based on SimMechanics 9

Trajectory Planning Simulation of 3-DoF Parallel Wrist Mecha...

引用

9th IEEE International Conference on Cyber technology in Automation, Control and intelligent systems, CYBER 2019

作者： Yang, Chen Xin, Liu Shimin, Wei Ying, Zhang Qineng, Huang School of Automation Beijing University of Posts and Telecommunications Beijing100876 China Beijing Institute of Spacecraft System Engineering Beijing Key Laboratory of Intelligent Space Robotic System Technology and Applications Beijing100094 China

ISBN: (纸本)9781728107691

In this paper, the trajectory planning problem of a 3-DoF parallel wrist mechanism based on SimMechanics is proposed, which is a symmetric spherical 3-RRR parallel mechanism. The formulation of the inverse kinematics for the mechanism is firstly established by D-H matrix method, and the analytical solution is obtained. Then, the trajectory planning analysis of the mechanism is performed. Finally, the mechanism model is constructed based on the SimMechanics module of Matlab/Simulink, and the trajectory planning simulation of the mechanism is carried out. The simulation results agree well with the theoretical results, which indicate that the proposed method is feasible and convenient for the trajectory simulation of parallel mechanisms. © 2019 IEEE.

关键词： Inverse kinematics

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Figure-ground image segmentation via semantic information

Figure-ground image segmentation via semantic information

引用

2019 IEEE International Conference on Real-Time Computing and robotics, RCAR 2019

作者： Yuan, Ding Qiang, Jingjing Li, Jianfei Zhang, Hong Luo, Xiaoyan school of Astronautics Beihang University Beijing China Institute of Shanghai Academy of Space Flight Technology China Beijing Key Laboratory of Intelligent Space Robotic System Technology and Applications Institute of Spacecraft System Engineering CAST China

ISBN: (纸本)9781728137261

—Image segmentation is a technique to segment the image into particular regions which are consistent in some specific characteristics. It is still a non-trivial task to segment the foreground from the background completely, as these regions are seldom uniform in color or texture which are defined as commonly-used low-level features adopted in the traditional techniques. In this work we present a new segmentation framework by employing the semantic information, which is classified as the high-level visual features and holds important clue to indicate the foreground from the background. Firstly, the image is segmented hierarchically by using the semantic edge constraint, and the result is represented as an Ultrametric Contour Map (UCM). Then the UCM is employed in the segmentation energy function as the data term and smoothness term. Finally, the optimal segmentation labels are obtained via the Graph-cut. Experiments achieve good performance testing on the MSRC 21 dataset. © 2018 IEEE

关键词： Textures

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Research on obstacle detection and path planning based on visual navigation for mobile robot

Research on obstacle detection and path planning based on vi...

引用

作者： Yixiao Zheng Bixi Yan Chao Ma Xinyu Wang Haoyang Xue School of Instrument Science and Optoelectronic Engineering Beijing Information Science and Technology University Beijing Key Laboratory of Intelligent Space Robotic Systems Technology and Applications Beijing Institute of Spacecraft System Engineering

Both obstacle and path planning are of significance for autonomous visual navigation of a mobile robot which is able to realize free movement and obstacle *** this paper,a scheme of obstacle detection which is based on binocular vision to identify obstacles is constructed and it is combined with improved A* algorithm for obstacle avoidance motion for mobile robot ***,a binocular vision system to detect the robot's perception of the environment is used and the visual information is *** a Gaussian filter is used to reduce the noise in the image,and the grayscale image is obtained through the binocular vision *** gray scale map is matched with SAD(Sum of Absolute Differences) in order to obtain the disparity image with ***,the location information of the obstacle is extracted through the environmental depth information contained in the disparity image,and the improved A* algorithm is used as the path planning algorithm in this paper,which can modify the path of the planning ***,the detection experiment of the robot visual obstacle avoidance system was established and the optimal path was *** examples show that,the obstacle avoidance system can complete the task of obstacle detection and give a better path for the mobile robot.

关键词： image filter Research on obstacle detection and path planning based on visual navigation for mobile robot

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