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Computational diffraction-limited imaging with a non-imaging spatial information transfer lens

Photonics Research 2024年第10期12卷 2265-2278页

作者： YINGLI LIU ZHIHUI DING FENGXU GUO CHENG GUO SHENGNAN JIA HAIFENG LI RENGMAO WU XU LIU State Key Laboratory of Extreme Photonics and Instrumentation College of Optical Science and EngineeringZhejiang UniversityHangzhou 310027China Faculty of Computing Harbin Institute of TechnologyHarbin 150001China Department of General Surgery Sir Run Run Shaw HospitalSchool of MedicineZhejiang UniversityHangzhou 310000China

The demand for low-cost,high-performance miniaturized optical imaging systems requires creating a new imaging *** this paper,we propose an imaging paradigm that achieves diffraction-limited imaging with a non-imaging spatial information transfer *** spatial information transfer lens realizes a perfect match between the space–bandwidth product(SBP)of the lens and that of the image sensor so that the collected spatial information from the object can be totally recorded and fully resolved by the image sensor.A backward wave propagation model is developed to reconstruct the object by propagating the light wave modulated by the information transfer lens back from the image space to object *** proposed imaging paradigm breaks the point-to-point imaging structure and removes the focusing-distance constraint,allowing a flexible arrangement of the object and the image sensor along the optical axis with a compact form factor of the optical *** experimentally demonstrate the versatility and effectiveness of the proposed imaging *** proposed imaging paradigm is low-cost,simple in configuration,flexible in arrangement,and diffraction limited with great potential applications in biomedical imaging.

关键词： transfer arrangement image

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Exploration of electron and ion thermodynamic models in laser-plasma expansion

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Science China(Physics,Mechanics & Astronomy) 2025年

作者： Yuan Hu Zilin Huang Yong Cao Quanhua Sun Heji Huang Chengyuan Ding Zhan Wang State Key Laboratory of High Temperature Gas Dynamics Institute of Mechanics Chinese Academy of Sciences School of Engineering Science University of Chinese Academy of Sciences Department of Mechanical Engineering & Automation Harbin Institute of Technology (Shenzhen) Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of Mechanics Chinese Academy of Sciences

The expansion of laser-produced plasma（LPP）, an important process to be understood to design the debris mitigation system of an extreme ultraviolet（EUV） light source, is governed by its associated electron and ion thermodynamics, the modeling of which is, however, a subject of debate. By applying the polytropic equation of state（EoS） for both electron and ion, we have derived the hydrodynamic-based self-similar solutions for an expanding plasma slab with finite ion temperature. The effects of electron and ion thermodynamics on plasma expansion and ion acceleration are investigated. We show that the unusual negative-correlation thermodynamic model for electrons in the hydrodynamic description of plasma expansion is an outcome of the interactions between the electrons following a nonequilibrium kappa distribution and the inherent plasma-induced electric field from a kinetic point of view. The comparisons between the self-similar solutions and the recent experiment data reveal that the electron is better characterized by the nonequilibrium kappa-based thermodynamic model with suprathermal population than the common equilibrium Boltzmann one. For thermal-ion expansion, it is found that the polytropic index for ion thermodynamics（γi） is about2, in contrast to γi= 3 for the adiabatic assumption made in earlier studies.

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Resonance-enhanced generation of optical harmonics from dielectric metasurfaces 14

Resonance-enhanced generation of optical harmonics from diel...

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Metamaterials XIV 2024

作者： Tonkaev, Pavel Lai, Fangxing Song, Qinghai Kruk, Sergey Koshelev, Kirill Kivshar, Yuri Nonlinear Physics Center Research School of Physics Australian National University CanberraACT2601 Australia Ministry of Industry and Information Technology Key Lab of Micro-Nano Optoelectronic Information System Guangdong Provincial Key Laboratory of Semiconductor Optoelectronic Materials and Intelligent Photonic Systems Harbin Institute of Technology Shenzhen518055 China

ISBN: (纸本)9781510672987

Nonlinear dielectric metasurfaces provide a promising platform to control and manipulate the optical frequency conversion at the nanoscale, suggesting new applications in imaging, lasing, and sensing. Here, we engage symmetry-broken silicon metasurfaces to enhance the second- and third-harmonic generation. We design and fabricate amorphous silicon metasurfaces supporting optical bound states in the continuum and guided-mode resonances, which greatly boost light-matter interaction resulting in several-order enhancements in both second- and third-harmonic generation. © 2024 SPIE.

关键词： Harmonic analysis

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Design of a novel flexible assistive hand exoskeleton 37

Design of a novel flexible assistive hand exoskeleton

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37th Youth Academic Annual Conference of Chinese Association of Automation, YAC 2022

作者： Li, Guotao Cheng, Long Gao, Zhengrun Lu, Jilong Zhao, Yanjiang Institute of Automation State Key Laboratory of Management and Control for Complex Systems Chinese Academy of Sciences Beijing100190 China Fudan University The National Clinical Research Center for Aging and Medicine Shanghai China Harbin University of Science and Technology Key Laboratory of Advanced Manufacturing and Intelligent Technology Ministry of Education Harbin150080 China Intelligent Machine Institute Harbin University of Science and Technology Harbin150080 China

ISBN: (纸本)9781665465366

Hand paralysis caused by stroke, spinal cord injury, or neurological trauma has a significant impact on the independence and quality of life of the patients. The hand exoskeleton can provide hand assistance and improve the patient's grasp. In this article, a novel wearable flexible hand exoskeleton is proposed to assist users in activities of daily life. To create a simple and lightweight assistive hand exoskeleton, 3D printing is used to manufacture most of the components, and a remote drive system is designed to reduce the weight of the hand exoskeleton. A ball pair device and a slider device are used to ensure the freedom of the thumb and the adaptability of the hand exoskeleton to different hand sizes. Finally, the experiments are conducted to verify that the hand exoskeleton can achieve motion assistance. © 2022 IEEE.

关键词： 3D printing

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Flexible Catch Claw-type Space Debris Capture Mechanism Based on Constant Torque Spring Deployment 17

Flexible Catch Claw-type Space Debris Capture Mechanism Base...

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17th IEEE International Conference on Mechatronics and Automation, ICMA 2020

作者： Sun, Kui Chen, Kailun Harbin Institute of Technology State Key Laboratory of Robotics and System Harbin Heilongjiang Province China

ISBN: (纸本)9781728164151

Space debris cleaning technology can not only save scarce orbit resources, but also protect satellites and space stations in orbit, which has important research significance. Combination of reliability and adaptability is the key for space debris cleaning devices to capture debris. A design scheme of flexible catch claw-type space debris capture mechanism based on constant torque spring deployment is proposed, which has the advantages of light weight, high capture reliability and high adaptability. The new flexible catching mechanism is mainly composed of a multi-finger flexible catching claw, a transmission device, and a locking device. In the multi-finger flexible catching claw, a constant torque spring is used as a passive drive deployment mechanism, and a carbon fiber rod is used as an actuator. The transmission device uses a ball screw to drive the link mechanism to move. The locking device provides a controllable deployment function at a predetermined position. This paper introduces the structure design of the capture mechanism and the research on synchronized deployment of the catch claws. Finally, the kinetic simulation results for evaluating the capture performance are given. © 2020 IEEE.

关键词： Space debris

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Global Fused Multi-Resolution Semantic Interactive Network for low contrast Infrared Iceberg Detection

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IEEE Sensors Journal 2025年

作者： Ma, Xinyu Li, Yang Chen, Fanglin Zhang, Qiming Guo, Fuhai Zhao, Bin Su, Fulin Harbin Institute of Technology Research Institute of Electronic Engineering Harbin150001 China Ministry of Industry and Information Technology Key Laboratory of Marine Environmental Monitoring and Information Processing Harbin150001 China CSSC Marine Technology Co. Ltd Department of System Integration Xinghuo Road 4 Science park Beijing100070 China Harbin Institute of Technology Institute of Electronic Engineering Harbin150001 China Institute of Rehabilitation Medicine China Harbin Institute of Technology School of Electronics and Information Engineering Department of Information Engineering Harbin150001 China

Ice floes and icebergs pose a deadly threat to ships. Ensuring safe navigation by timely detecting these hazards through shipborne detection systems represents a potent solution. Infrared iceberg detection stands out due to its exceptional visual capability and immunity to light and weather conditions, enhancing detection robustness. However, existing infrared small target detection methods struggle to effectively capture the features of the low-contrast ice target, making it difficult to detect the target. In this paper, we propose a Global Fused Multi-resolution Semantic Interactive Network (GMSINet) for feature extraction of ice targets. Firstly, we design a novel parallel encoder structure for complementary feature extraction. The structure incorporates an additional global branch that effectively retrieves submerged low-contrast features of the targets. The global branch effectively retrieves submerged low-contrast features of the targets. The local branch obtains the semantic feature of the target and reduces the loss of downsampling. Furthermore, we introduce the Multi-resolution Feature Interactive (MFI) module, which augments semantic features through the interaction of features across different resolutions. To further refine these enhanced features, we design the De-redundancy Block (DB), which emphasizes pertinent features while suppressing irrelevant ones. Finally, experimental results on our self-conducted SFIIT dataset and the publicly available SIRST dataset demonstrate that the proposed method performs satisfactorily in infrared target detection. © 2001-2012 IEEE.

关键词： Semantic Segmentation

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A Risk-sensitive Automatic Stock Trading Strategy Based on Deep Reinforcement Learning and Transformer

A Risk-sensitive Automatic Stock Trading Strategy Based on D...

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IEEE International Conference on Automation Science and Engineering (CASE)

作者： Linyu Li Qi Liu Yanjie Li Yongjin Mu Zheng Zhang Guangdong Key Laboratory of Intelligent Morphing Mechanisms and Adaptive Robotics and School of Mechanical Engineering and Automation the Harbin Institute of Technology Shenzhen China

ISBN: (数字)9798350358513

ISBN: (纸本)9798350358520

Navigating the world of stock trading can be a daunting task, with its high risk, high reward potential, and intricate market dynamics. For investors and financial researchers, making informed investment decisions is essential. To our knowledge, limited by insufficient feature representation in highly dynamic trading scenarios, existing rule-based and machine learning-based methods struggle to extract complex intrinsic information from the stock market. Thus, with the huge success of reinforcement learning (RL) in sequential decision-making tasks and the powerful feature extraction capabilities of Transformer, this paper proposes an automatic stock trading method based on RL and Transformer. First, data from multiple stocks are collected into Transformer to extract the correlations among stocks. Then, the output of Transformer is used as the state input for deep RL, and the trading action is obtained. Furthermore, we propose a risk-sensitive reward function by adding the turbulence index to avoid risk. Experimental results on Dow Jones 30 constituent stocks show that the proposed method outperforms baselines regarding profit, risk, and comprehensive indicators.

关键词： Measurement Learning systems Navigation Transformers Feature extraction Solids Indexes Data mining Stock markets Investment

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Intelligent sensing and control for aerospace unmanned systems

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Aerospace systems 2022年第2期5卷 167-169页

作者： Li, Yuankai Ding, Liang Guo, Qing Pan, Han School of Aeronautics and Astronautics University of Electronic Science and Technology of China 2006 Xiyuan Avenue Chengdu China State Key Laboratory of Robotics and Systems Harbin Institute of Technology 2 Yikuang Street Harbin China School of Aeronautics and Astronautics Shanghai Jiao Tong University 800 Dongchuan Road Shanghai China

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An Environmental-Complexity-Based Navigation Method Based on Hierarchical Deep Reinforcement Learning

An Environmental-Complexity-Based Navigation Method Based on...

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IEEE International Conference on robotics and Automation (ICRA)

作者： Pengbin Chen Qi Liu Yanjie Li Shuaikang Ma Guangdong Key Laboratory of Intelligent Morphing Mechanisms and Adaptive Robotics and School of Mechanical Engineering and Automation The Harbin Institute of Technology Shenzhen China

ISBN: (数字)9798350384574

ISBN: (纸本)9798350384581

Navigation methods based on deep reinforcement learning (RL) have recently exhibited superior performance, particularly for navigation in dynamic environments. However, most existing methods solely rely on deep neural network feature encoders to extract features from raw LiDAR data, lacking an explicit representation of environmental structure. This limitation hinders effective environmental representation and interpretability, constraining navigation performance improvement. To solve this problem, we propose two quantitative metrics based on laser scans, which explicitly represent environmental complexity and show great interpretability. Furthermore, we propose an environmental-complexity-based navigation method based on hierarchical deep RL with the proposed metrics. Experimental results show that the proposed method achieves better navigation performance than baselines, especially in challenging scenarios with corners and dynamic obstacles.

关键词： Measurement Laser radar Navigation Lasers Artificial neural networks Feature extraction Deep reinforcement learning

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Analysis of Bifurcation and Chaotic Behavior of the Micro Piezoelectric Pipe-Line Robot Drive system with Stick - Slip Mechanism

SSRN

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SSRN 2023年

作者： Xing, Jichun Ning, Chao Zhi, Yuan Howard, Ian School of Mechanical Engineering Yanshan University Qinhuangdao066004 China State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin150001 China School of Civil and Mechanical Engineering Curtin University Perth6001 Australia

Pipeline robots using the conventional driving mode have encountered a bottleneck in miniaturization. To address this problem, a micro piezoelectric pipeline robot based on the inertia stick-slip driving principle is proposed in this paper. The robot is well suited to the inspection needs of micro pipes. However, undesirable design parameters found during the structural optimization phase can lead to unstable operation and reduced load capacity of the robot, and can even cause the drive system to stop with chaotic behavior. Therefore, the nonlinear dynamics model of the four degree of freedom discrete system of the pipeline robot is established. The Runge-Kutta method is used to solve the dynamic response of each nonlinear subsystem. The nonlinear dynamical behavior of the system is analyzed through the bifurcation diagram, time domain diagram, phase diagram, Poincaré map and power spectrum diagram of each subsystem response. The stable operation intervals of the machine and electrical parameters in the drive system are given, and the conditions for the occurrence of chaotic behavior are determined. This research can help to determine and optimize the structural parameters of the piezoelectric stick-slip pipeline robot, thus avoiding chaotic behavior and ensuring that the robot maintains good operational performance. © 2023, The Authors. All rights reserved.

关键词： Stick-slip

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