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A novel space target-tracking method based on generalized Gaussian distribution for on-orbit maintenance robot in Tiangong-2 space laboratory

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Science China(Technological Sciences) 2019年第6期62卷 1045-1054页

作者： MO Yang JIANG ZhiHong LI Hui YANG Hong HUANG Qiang School of Mechatronic Engineering Beijing Institute of Technology Beijing 100081 China Beijing Advanced Innovation Center for Intelligent Robots and Systems Beijing 100081 China Key Laboratory of Biomimetic Robots and Systems Ministry of Education Beijing 100081 China Institute of Manned Spacecraft System Engineering China Academy of Space Technology Beijing 100080 China

Accurate target tracking based on visual images is the key for intelligent robots to assist or replace astronauts to work in space station. However, the special space environment such as non-uniform illumination and high-energy particle radiation is a huge challenge, which may lead to complex noise coupling in vision image. This paper proposes a novel method for accurate target tracking, the essence of which is the Retinex image enhancement algorithm in CIELAB color space(LAB-GRetinex) and the generalized maximum correntropy Kalman filter(GMCKF) which are all based on generalized Gaussian distribution. The LABGRetinex algorithm chooses the CIELAB color space, which is closer to the human vision, as the processing color space, and the generalized Gaussian distribution can estimate the light image accurately, so the influence of non-uniform illumination can be reduced effectively. Meanwhile, the GMCKF algorithm adopts the generalized correntropy criterion based on the generalized Gaussian distribution to replace the minimum mean square error(MMSE) criterion to realize the optimal filtering effect under the complex non-Gaussian noise, which can improve the target tracking accuracy. Sufficient ground simulation experiments and application experiments in the Tiangong-2 space laboratory verify the effectiveness of the proposed algorithm which can track the target accurately in the special space environment and provide the precise pose information for on-orbit robot maintenance verification. This research lays a technical foundation for the application of intelligent robot in the construction and operation on space station in the future.

关键词： space robot LAB-GRetinex GMCKF target tracking

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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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The impact of rain to observed signal from Chinese Gaofen-3 synthetic aperture radar in typhoons

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Acta Oceanologica Sinica 2019年第11期38卷 121-133页

作者： Jian Shi Jiachen Hu Weizeng Shao Xiaoqing Wang Xinzhe Yuan Liangbo Zhao Xiaofeng Li College of Meteorology and Oceanography National University of Defense TechnologyNanjing 211101China Marine Science and Technology College Zhejiang Ocean UniversityZhoushan 316022China School of Electronics and Communication Engineering Sun Yat-sen UniversityGuangzhou 510275China Key Laboratory of Space Ocean Remote Sensing and Application National Satellite Ocean Application ServiceBeijing 100081China Institute of Spacecraft System Engineering China Academy of Space TechnologyBeijing 100094China

Gaofen-3(GF-3),a Chinese civil synthetic aperture radar(SAR)at C-band,has operated since August ***,several typhoons have been captured by GF-3 around the China Seas over its last two-year *** this study,six images acquired in Global Observation(GLO)and Wide ScanSAR(WSC)modes at verticalvertical(VV)polarization channel are *** work focuses on investigating the observation of rainfall using GF-3 *** images were collocated with winds from the European Centre for Medium-Range Weather Forecasts(ECMWF),significant wave height simulated from the WAVEWATCH-III(WW3)model,sea surface currents from climate forecast system version 2(CFSv2)of the National Centers for Environmental Prediction(NCEP)and rain rate data from the Tropical Rainfall Measuring Mission(TRMM)*** surface roughness,was compared with the normalized radar cross section(NRCS)from SAR observations,and indicated a 0.8 correlation(COR).We analyzed the dependences of the difference between model-simulated NRCS and SARmeasured NRCS on the TRMM rain rate and WW3-simulated significant wave *** was found that the effects of rain on SAR damps the radar signal at incidence angles ranging from 15°to 30°,while it enhances the radar signal at incidence angles ranging from 30°to 45°and incidence angles smaller than 10°.This behavior is consistent with previous studies and an algorithm for rain rate retrieval is anticipated for GF-3 SAR.

关键词： Gaofen-3 synthetic aperture radar typhoon

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Learning a faster locomotion gait for a quadruped robot with model-free deep reinforcement learning

Learning a faster locomotion gait for a quadruped robot with...

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2019 IEEE International Conference on robotics and Biomimetics, ROBIO 2019

作者： Hu, Biao Shao, Shibo Cao, Zhengcai Xiao, Qing Li, Qunzhi Ma, Chao Beijing University of Chemical Technology College of Information Science and Technology Beijing100029 China Beijing Institute of Spacecraft System Engineering Beijing Key Laboratory of Intelligent Space Robotic Systems Technology and Applications Beijing China

ISBN: (纸本)9781728163215

Quadruped robots have great agility, flexibility and stability, which enables them to walk through uneven terrain. Motion control of legged robots is always a difficult problem. Previous approaches mostly either use a predefined gait that results in clumsy and unnatural behavior, or use reinforcement learning approach to generate a gait strategy that needs longtime computation and elegant network design. In this paper, we present an effective approach that uses deep reinforcement learning with prior knowledge to optimize the gait of quadruped robot. By using a specific quadruped robot walking gait as a priori knowledge, this approach adopts the technique of distributed proximal policy optimization to optimize the search for better gait. The proposed approach does not require modelling of complex robots, and has good network convergence speed and learning effect. Simulation results demonstrate that our proposed approach converges faster than other deep reinforcement learning methods without prior knowledge. Besides, our achieved gait has higher speed that is 50% faster than the trot gait without optimization. © 2019 IEEE.

关键词： Reinforcement learning

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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...

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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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Automatic detection of Cyanobacterial blooms using multi-source optical satellite imagery: method development and application

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Ecological Indicators 2025年 176卷

作者： Hailong Zhang Chen Lu Deyong Sun Xiaomin Ye Shengqiang Wang Quan Qin State Key Laboratory of Climate System Prediction and Risk Management Nanjing University of Information Science and Technology Nanjing 210044 China Key Laboratory of Coastal Zone Exploitation and Protection Ministry of Natural Resources Nanjing 210017 China School of Marine Sciences Nanjing University of Information Science and Technology Nanjing 210044 China Key Laboratory of Space Ocean Remote Sensing and Application Ministry of Natural Resources Beijing 100081 China Shandong Provincial Climate Center Jinan 250031 China

Cyanobacterial blooms (CyanoBloom) are a widespread environmental concern in lakes, and optical satellite imagery has been widely used to monitor their spatiotemporal dynamics. Many spectral-based CyanoBloom detection methods rely on Rayleigh- or atmosphere-corrected surface reflectance. However, these methods require ancillary atmospheric data and preprocessing procedures, thereby limiting their operational efficiency and scalability. The potential of multi-source satellite imagery remains underexploited due to the lake of robust methods for automatic CyanoBloom detection across various satellite platforms. To address this challenge, we proposed a novel automatic CyanoBloom detection (ACD) method that directly utilizes satellite top-of-atmosphere reflectance ( R TOA ) data. Cross-index and cross-sensor analyses confirmed the high detection accuracy and robustness of the ACD method against atmospheric and observational variations. The method was successfully applied to various inland lakes, including Lake Taihu, Lake Chaohu, Lake Dianchi, and Lake Xingyun in China, Lake Okeechobee in the United States, and Lough Neagh in Northern Ireland. Requiring only for four spectral bands (blue, green, red, and near-infrared), the ACD method was compatible with various optical sensors, including HY1C/D-CZI, GF-WFV, GF4-PMS, HJ-CCD, Sentinel2-MSI, Landsat9-OLI, and Terra-MODIS. This study presents a novel automatic and rapid approach for detecting CyanoBloom in lakes, providing valuable technical support for water quality monitoring and bloom management.

关键词： Cyanobacterial bloom Automatic detecting Satellite R TOA Optical satellite imagery

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Satellites reveal hot spots of ocean changes in the early 21st century

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Science Advances 2025年第23期11卷

作者： Zhenghao Li Deyong Sun Shengqiang Wang Yu Huan Hailong Zhang Yijun He State Key Laboratory of Climate System Prediction and Risk Management Nanjing University of Information Science and Technology Nanjing 210044 China. School of Marine Sciences Nanjing University of Information Science and Technology Nanjing 210044 China. Key Laboratory of Space Ocean Remote Sensing and Application Ministry of Natural Resources Beijing 100081 China. School of Marine Technology and Geomatics Jiangsu Ocean University Lian Yungang 222000 China.

Ocean change leaves a potentially important imprint on ocean colorimetry. Here, we present an overview and current evaluation of the global ocean color variability from 1998 to 2022, and satellites observe that 36% of oceans (~122 million square kilometers, derived from valid observations) have experienced changes (P < 0.1). In this context, 25% of the area (formerly blue hue) is turning light blue or green, while the remaining 11% becomes bluer, mainly concentrating in the low-latitude oceans. This study further identifies a “direct” notable impact of both sea surface temperature (SST) and climate on ocean colorimetry tendency and anomaly, especially in the low-latitude oceans. Extreme SST events cause “distinct” ocean colorimetry anomalies, although 94% of cases involve relatively small SST fluctuations. Causal analysis reveals important impacts of climate change on equatorial ocean dynamics, particularly ENSO events. Our findings prove the low-latitude oceans as one of the core changing regions that respond to climate change in the early 21st century.

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A Method for Obtaining Contact Force between Catheter Tip and Vascular Wall in Master-slave robotic system

A Method for Obtaining Contact Force between Catheter Tip an...

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IEEE International Conference on Mechatronics and Automation

作者： Xiaoliang Jin Shuxiang Guo Jian Guo Peng Shi Dapeng Song Faculty of Engineering and Design Kagawa University 2217-20 Hayashi-cho Takamatsu Kagawa Japan Key Laboratory of Convergence Medical Engineering System and Healthcare Technology the Ministry of Industry and Information Technology School of Life Science Beijing Institute of Technology Beijing China Tianjin Key Laboratory for Control Theory and Application in Complicated Systems and Intelligent Robot Laboratory Tianjin University of Technology Tianjin China

ISBN: (数字)9781728164168

ISBN: (纸本)9781728164175

In the research of vascular interventional surgery robotic system, the force information acquisition of surgical tools (guidewires and catheters) has a significant affect on the safety of surgery, especially the contact force between the catheter tip and vascular wall. Therefore. In order to obtain this contact force, we noticed the pressure sensitive rubber because of its piezoresistive effect and easy processing into any shape. a force sensor based on the pressure sensitive rubber was developed in this paper. Once a force is applied on the force sensor attached to the catheter tip, the contact force can be approximated by the piezoresistive effect of the pressure sensitive rubber. The feasibility of the developed force sensor was verified by the experiments in “Vitro”. And the results showed that the force sensor was developed in this paper can accurately detect the contact force between the catheter tip and vascular wall at different positions in the vascular model, the extraction of contact force information of catheter tip is of great significance to the safety of surgery, and the application potential of pressure sensitive rubber.

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