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Haptic display for virtual reality: progress and challenges

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Virtual Reality & Intelligent Hardware 2019年第2期1卷 136-162页

作者： Dangxiao WANG Yuan GUO Shiyi LIU Yuru ZHANG Weiliang XU Jing XIAO State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijing 100083China Beijing Advanced Innovation Center for Biomedical Engineering Beihang UniversityBeijing 100083China Peng Cheng Laboratory Shenzhen 518055China Department of Mechanical Engineering University of AucklandAuckland 1142New Zealand School of Computer Science and the Robotics Engineering Program Worcester Polytechnic InstituteWorcesterMA 01609-2280USA

Immersion, interaction, and imagination are three features of virtual reality (VR). Existing VR systems possess fairly realistic visual and auditory feedbacks, and however, are poor with haptic feedback, by means of which human can perceive the physical world via abundant haptic properties. Haptic display is an interface aiming to enable bilateral signal communications between human and computer, and thus to greatly enhance the immersion and interaction of VR systems. This paper surveys the paradigm shift of haptic display occurred in the past 30 years, which is classified into three stages, including desktop haptics, surface haptics, and wearable haptics. The driving forces, key technologies and typical applications in each stage are critically reviewed. Toward the future high-fidelity VR interaction, research challenges are highlighted concerning handheld haptic device, multimodal haptic device, and high fidelity haptic rendering. In the end, the importance of understanding human haptic perception for designing effective haptic devices is addressed.

关键词： Haptic display Virtual reality Desktop haptics Surface haptics Wearable haptics Multimodal haptics

Image-guided breast biopsy of MRI-visible lesions with a hand-mounted motorised needle steering tool

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arXiv 2021年

作者： Lagomarsino, Marta Groenhuis, Vincent Casadio, Maura Welleweerd, Marcel K. Siepel, Françoise J. Stramigioli, Stefano Laboratory Faculty of Electrical Engineering Mathematics and Computer Science University of Twente Drienerlolaan 5 Enschede7522NB Netherlands Department of Informatics Bioengineering Robotics and Systems Engineering University of Genoa Via Opera Pia 13 Genoa16145 Italy Department of Advanced Robotics Istituto Italiano di Tecnologia Genoa Italy Department of Electronics Information and Bioengineering Politecnico di Milano Milan Italy

A biopsy is the only diagnostic procedure for accurate histological confirmation of breast cancer. When sonographic placement is not feasible, a Magnetic Resonance Imaging(MRI)-guided biopsy is often preferred. The lack of real-time imaging information and the deformations of the breast make it challenging to bring the needle precisely towards the tumour detected in pre-interventional Magnetic Resonance (MR) images. The current manual MRI-guided biopsy workflow is inaccurate and would benefit from a technique that allows real-time tracking and localisation of the tumour lesion during needle insertion. This paper proposes a robotic setup and software architecture to assist the radiologist in targeting MR-detected suspicious tumours. The approach benefits from image fusion of preoperative images with intraoperative optical tracking of markers attached to the patient's skin. A hand-mounted biopsy device has been constructed with an actuated needle base to drive the tip toward the desired direction. The steering commands may be provided both by user input and by computer guidance. The workflow is validated through phantom experiments. On average, the suspicious breast lesion is targeted with a radius down to 2.3 mm. The results suggest that robotic systems taking into account breast deformations have the potentials to tackle this clinical challenge. Copyright © 2021, The Authors. All rights reserved.

关键词： Biopsy

Transition Metal-Vacancy Point Defects in Zinc Oxide as Deep-Level Spin Qubits

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arXiv 2025年

作者： Zhang, Shimin Park, Taejoon Perez, Erik Li, Kejun Wang, Xingyi Wang, Yanyong Vega Bazantes, Jorge D. Zhang, Ruiqi Sun, Jianwei Fu, Kai-Mei C. Seo, Hosung Ping, Yuan Department of Materials Science and Engineering University of Wisconsin-Madison 53706 United States SKKU Advanced Institute of Nanotechnology Sungkyunkwan University Gyeonggi Suwon16419 Korea Republic of Department of Energy Systems Research Department of Physics Ajou University Gyeonggi Suwon16499 Korea Republic of Department of Physics University of California Santa CruzCA95064 United States Department of Electrical and Computer Engineering University of Washington SeattleWA98195 United States School of Science & Engineering Tulane University 6823 St Charles Ave New OrleansLA70118 United States Department of Physics University of Washington SeattleWA98195 United States Physical Sciences Division Pacific Northwest National Laboratory RichlandWA99352 United States Department of Quantum Information Engineering Sungkyunkwan University Gyeonggi Suwon16419 Korea Republic of Center for Quantum Information Korea Institute of Science and Technology Seoul02792 Korea Republic of Department of Physics University of Wisconsin-Madison 53706 United States Department of Chemistry University of Wisconsin-Madison 53706 United States

Wide band gap oxides are promising host materials for spin defect qubits, offering unique advantages such as a dilute nuclear spin environment. Zinc oxide (ZnO), in particular, can achieve exceptional high purity, which enables long spin coherence time. In this work, we theoretically search for deep-level point defects in ZnO with optimal physical properties for optically-addressable spin qubits. Using first-principles calculations, we predict the Molybdenum-vacancy complex defect (MoZnvO)2+ in ZnO to own promising spin and optical properties, including spin-triplet ground state, optical transition in the visible to near-infrared range with high quantum yield, allowed intersystem crossings with a sizable optically-detected magnetic resonance contrast, and long spin T2 and T∗2. Notably, we find the Huang-Rhys factor of the defect to be around 5, which is significantly smaller than the typical range of 10-30 for most known defects in ZnO. Furthermore, we compare the spin decoherence driven by the nuclear spin bath and paramagnetic impurity baths. We find that the paramagnetic impurities are very effective in causing spin decoherence even with very low concentrations, implying that they can likely dominate the spin decoherence in ZnO even after isotopic purification. Using the computed excited-state energies and kinetic rates as inputs, we predict the ODMR contrast and propose a new protocol for spin qubit initialization and readout, which could be generalized to other systems with forbidden axial intersystem crossings. © 2025, CC BY.

关键词： Zinc oxide

Emerging chiral optics from chiral interfaces

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Physical Review B 2021年第19期103卷 195405-195405页

作者： Xinyan Zhang Yuhan Zhong Tony Low Hongsheng Chen Xiao Lin Interdisciplinary Center for Quantum Information State Key Laboratory of Modern Optical Instrumentation ZJU-Hangzhou Global Scientific and Technological Innovation Center Zhejiang University Hangzhou 310027 China International Joint Innovation Center Key Lab. of Advanced Micro/Nano Electronic Devices & Smart Systems of Zhejiang The Electromagnetics Academy at Zhejiang University Zhejiang University Haining 314400 China Department of Electrical and Computer Engineering University of Minnesota Minneapolis Minnesota 55455 USA

Twisted atomic bilayers are emerging platforms for manipulating chiral light-matter interaction at the extreme nanoscale, due to their inherent magnetoelectric responses induced by the finite twist angle and quantum interlayer coupling between the atomic layers. Recent studies have reported the direct correspondence between twisted atomic bilayers and chiral metasurfaces, which features a chiral surface conductivity, in addition to the electric and magnetic surface conductivities. However, far-field chiral optics in light of these constitutive conductivities remains unexplored. Within the framework of the full Maxwell equations, we find that the chiral surface conductivity can be exploited to realize perfect polarization transformation between linearly polarized light. Remarkably, such an exotic chiral phenomenon can occur either for the reflected or transmitted light. Moreover, we reveal that all transmitted light through the judiciously designed chiral surface conductivity can always have the polarization different from the incident light, irrespective of the incident angle.

关键词： Electromagnetism Extraordinary optical transmission Light-matter interaction Refraction

Adaptive event-triggered PID controllers for linear discrete-time plants

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Adaptive event-triggered PID controllers for linear discrete...

Chinese Control Conference (CCC)

作者： Hao Yu Zhe Guan Tongwen Chen Toru Yamamoto Department of Electrical and Computer Engineering University of Alberta Edmonton AB Canada Data-Driven Smart Systems Collaborative Research Laboratory Hiroshima University Hiroshima Japan Graduate School of Advanced Science and Engineering Hiroshima University Hiroshima Japan

ISBN: (数字)9789881563903

ISBN: (纸本)9781728165233

This paper studies adaptive event-triggered PID controllers for 2nd-order linear discrete-time plants for set-point tracking. A new adaptive law is designed by introducing a decay parameter to improve the robustness of the closed-loop system. By utilizing the extra robustness, an absolute type of event-triggering conditions is proposed, where the threshold parameter is co-designed with the adaptive laws. Then, the closed-loop system is formulated into a nonlinear interconnected system among the tracking errors, the differences of outputs, and the parameter estimation errors. A rigorous proof of stability is provided to ensure that the tracking error converges to a vicinity of zero when the initial state belongs to some compact sets. Finally, numerical simulations are given to illustrate the efficiency and feasibility of the proposed results.

关键词： Adaptive systems Closed loop systems Stability analysis PI control PD control Robustness Adaptation models

One to many: Adaptive instrument segmentation via meta learning and dynamic online adaptation in robotic surgical video

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arXiv 2021年

作者： Zhao, Zixu Jin, Yueming Lu, Bo Ng, Chi-Fai Dou, Qi Liu, Yun-Hui Heng, Pheng-Ann The Department of Computer Science and Engineering The Chinese University of Hong Kong Hong Kong The T Stone Robotics Institute The Department of Mechanical and Automation Engineering The Chinese University of Hong Kong Hong Kong Guangdong-Hong Kong-Macao Joint Laboratory of Human-Machine Intelligence-Synergy Systems Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences China The Department of Surgery The Chinese University of Hong Kong Hong Kong

Surgical instrument segmentation in robot-assisted surgery (RAS) - especially that using learning-based models - relies on the assumption that training and testing videos are sampled from the same domain. However, it is impractical and expensive to collect and annotate sufficient data from every new domain. To greatly increase the label efficiency, we explore a new problem, i.e., adaptive instrument segmentation, which is to effectively adapt one source model to new robotic surgical videos from multiple target domains, only given the annotated instruments in the first frame. We propose MDAL, a meta-learning based dynamic online adaptive learning scheme with a two-stage framework to fast adapt the model parameters on the first frame and partial subsequent frames while predicting the results. MDAL learns the general knowledge of instruments and the fast adaptation ability through the video-specific meta-learning paradigm. The added gradient gate excludes the noisy supervision from pseudo masks for dynamic online adaptation on target videos. We demonstrate empirically that MDAL outperforms other state-of-the-art methods on two datasets (including a real-world RAS dataset). The promising performance on ex-vivo scenes also benefits the downstream tasks such as robot-assisted suturing and camera control. Copyright © 2021, The Authors. All rights reserved.

关键词： Surgical equipment

Stream Cipher from Chaotic systems and High Gain Observers 3

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Stream Cipher from Chaotic Systems and High Gain Observers

3rd International Conference on advanced systems and Emergent Technologies, IC_ASET 2019

作者： Daldoul, Ines Tlili, Ali Sghaier National High School of Engineering of Tunis University of Tunis Laboratory of Advanced Systems Polytechnic School of Tunisia BP. 743 La Marsa Tunis2078 Tunisia Laboratory of Advanced Systems Polytechnic School of Tunisia BP. 743 La Marsa Tunis2078 Tunisia High Institute of Computer Science University of Tunis El Manar Tunisia

ISBN: (纸本)9781728113173

This paper proposes an advanced secured transmission of information method founded on synchronizing chaotic system with an optimal high gain observer. The challenging idea investigated in this work is to insulate the encryption process from the synchronization operations relying on the same chaotic system but with two different roles. First, the chaotic system is a part of the encryption process and generate pseudo-random sequence of signals, which will be treated with Exclusive-OR operations to form the cipher, and then the dynamic system will acts as a transmitter. In fact, the designed transmission scheme is established using an improved optimal nonlinear observer having the advantage to reconstruct the transmitter. Finally, the decryption operation is carried out by replacing the chaotic system by its estimation one. Numerical simulation based on an image encryption/decryption is conducted as an illustration to demonstrate the outstanding performances of the designed transmission method. © 2019 IEEE.

关键词： Cryptography

Recent advances of transition radiation: fundamentals and applications

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arXiv 2022年

作者： Chen, Ruoxi Gong, Zheng Chen, Jialin Zhang, Xinyan Zhu, Xingjian Chen, Hongsheng Lin, Xiao Interdisciplinary Center for Quantum Information State Key Laboratory of Extreme Photonics and Instrumentation ZJU-Hangzhou Global Scientific and Technological Innovation Center College of Information Science & Electronic Engineering Zhejiang University Hangzhou310027 China International Joint Innovation Center The Electromagnetics Academy Zhejiang University Zhejiang University Haining314400 China Department of Electrical and Computer Engineering Technion-Israel Institute of Technology Haifa32000 Israel School of Physics Zhejiang University Hangzhou310027 China Key Laboratory of Advanced Micro/Nano Electronic Devices & Smart Systems of Zhejiang Jinhua Institute of Zhejiang University Zhejiang University Jinhua321099 China Shaoxing Institute of Zhejiang University Zhejiang University Shaoxing312000 China

Transition radiation is a fundamental process of light emission and occurs whenever a charged particle moves across an inhomogeneous region. One feature of transition radiation is that it can create light emission at arbitrary frequency under any particle velocity. Therefore, transition radiation is of significant importance to both fundamental science and practical applications. In this paper, we provide a brief historical review of transition radiation and its recent development. Moreover, we pay special attention to four typical applications of transition radiation, namely the detection of high-energy particles, coherent radiation sources, beam diagnosis, and excitation of surface waves. Finally, we give an outlook for the research tendency of transition radiation, especially its flexible manipulation by exploiting artificially-engineered materials and nanostructures, such as gain materials, metamaterials, spatial-temporal materials, meta-boundaries, and layered structures with a periodic or non-periodic stacking. © 2022, CC BY.

关键词： Light emission

Robust multimodal federated learning for non-IID multimodal data with incompleteness

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Future Generation computer systems 2026年 174卷

作者： Songcan Yu Kaiming Zhu Feiyuan Liang Junbo Wang Krishna Kant Ling Yin Department of Computer Science and Technology Sichuan Police College Luzhou 646000 PR China Police Integration Computing Key Laboratory of Sichuan Province Chengdu 610206 PR China School of Intelligent Systems Engineering Sun Yat-Sen University Shenzhen 518107 PR China Department of Computer and Information Sciences Temple University Philadelphia USA Shenzhen Institute of Advanced Technology Chinese Academy of Sciences Shenzhen 518055 PR China

Federated learning (FL) provides a privacy-aware distributed learning framework using private data belonging to multiple users (or clients). Often the data is generated continuously by the sensors deployed by different clients and is increasingly multimodal. However, the data is invariably imbalanced across different modalities, and certain modalities may even be missing from some clients for certain periods due to sensor failure or unavailability. Furthermore, the available data across clients may not be identically distributed (non-IID). Non-IID data is already known to be a problem with FL, and incomplete modalities could worsen the results even further. Effectively fusing multimodal data with incompleteness and training a high-accuracy global model is still a challenging problem. To tackle this problem, we propose a novel framework called MFedNI that extracts cross-modal temporal features and adaptively adjusts the weights of each modality to mitigate the effect of modal incompleteness. The prototype contrastive learning (PCL)-based feature alignment method further improves the consistency of feature representations across clients. We evaluated MFedNI using two multimodal datasets, HAR and DEAP with different levels of incompleteness. The results demonstrate that MFedNI outperforms other approaches and can train highly accurate models on datasets comprising non-IID multimodal data with incompleteness.

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