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Unidirectional acoustic parametric amplification in space-time modulated membrane system

Unidirectional acoustic parametric amplification in space-ti...

ASME 2020 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, IDETC-CIE 2020

作者： Zhu, Xiaohui Li, Longqiu Zhang, Guangyu State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin Heilongjiang China

ISBN: (纸本)9780791883907

Space-time modulation puts a new twist on controlling wave behaviors and opens the door for unprecedented wave manipulation capabilities. Here we propose a space-time modulated membrane system aiming to realize the unidirectional parametric amplification. Two different approaches, continuous model and transfer matrix method, are applied to analyze the acoustic response of the system under a monochromatic incidence. In the proposed space-time modulated membrane system, these two methods are in good agreement with each other. Results show that under a monochromatic incidence from one end of the system, a harmonic is generated, and both the incident wave and generated wave exponentially grow along with the system. Our work demonstrates a metamaterial realization of unidirectional acoustic parametric amplifier via space-time modulated membranes, which offers a design platform for a number of applications in sensing, imaging and communication. Copyright © 2020 ASME.

关键词： Transfer matrix method

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A Biomimetic impedance controller for Robotic Hand Variable Stiffness Grasping 17

A Biomimetic impedance controller for Robotic Hand Variable ...

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

作者： Liu, Bingchen Jiang, Li Fan, Shaowei Li, Chongyang Harbin Institute of Technology State Key Laboratory of Robotics and System Harbin150080 China

ISBN: (纸本)9781728164151

The accuracy of human hand grasp is due to many reasons, e.g. the feedbacks of force, temperature, pressure, and position, etc. It is impossible to mimic this complicated system for a robotic hand. Therefore, simplification of the robotic control system with relative accurate operations is necessary. In this study, a biomimetic impedance controller was utilized on a robotic hand, where the control parameters were based on a biomechanical model of the human hand. The relationship between the grasp force and surface electromyography (sEMG) was measured, and the impedance of the joint was calculated through a series of dynamic vibration tests subsequently. The effectiveness of the biomimetic impedance controller is verified through human operating the robotic hand reproducing a variety of grasping tasks. © 2020 IEEE.

关键词： Biomimetics

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Health monitoring of pressure transmitter sensing line based on convolutional neural network

Health monitoring of pressure transmitter sensing line based...

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12th International Conference on Quality, Reliability, Risk, Maintenance, and Safety Engineering (QR2MSE 2022)

作者： T. He A. Xu K. Wang P. Zeng Laboratory of Industrial Control Network and System State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang People's Republic of China

Blockages of pressure transmitter sensing line are a recurring problem in nuclear plants. The traditional solution is to purge them with nitrogen periodically, which is time consuming and radiation intensive. It is thus desirable to monitor the status of sensing lines on-site. The noise analysis method is a promising method for sensing line health monitoring. However, the existing noise analysis methods, which evaluate the sensing line status by analyzing time domain or frequency domain features of process noise signal, are susceptible to working conditions of pressure transmitters. Further, blockage degree of the sensing line can not be determined by existing methods. Therefore, this paper proposes a machine learning based noise analysis method for health monitoring of pressure transmitter sensing line, in which 1-D Convolutional Neural Network (CNN) is used to extract features from process noise signals. Experimental results show that the proposed method achieved satisfactory results in diagnosis accuracy, false alarm rate and robustness of the model under different working conditions. Further, blockage degree of sensing line can also be evaluated

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Damage evolution mechanism and low-damage grinding technology of silicon carbide ceramics

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International Journal of Extreme Manufacturing 2025年第2期7卷 551-586页

作者： Chen Li Kechong Wang Oleg Zakharov Hailong Cui Mingtao Wu Tianchen Zhao Yongda Yan Yanquan Geng State Key Laboratory of Robotics and System(HIT) Harbin Institute of TechnologyHarbin 150001People’s Republic of China School of Mechatronics Engineering Harbin Institute of TechnologyHarbin 150001People’s Republic of China Moscow State University of Technology STANKINMoscow 127994Russia Sichuan Precision and Ultra-Precision Machining Engineering Technology Center Chengdu 610200People’s Republic of China College of Mechanical Engineering Quzhou UniversityQuzhou 324000People’s Republic of China Hunan Provincial Key Laboratory of High Efficiency and Precision Machining of Difficult-to-cut Material Hunan University of Science and TechnologyXiangtan 411201People’s Republic of China

Silicon carbide(SiC)ceramics are extensively utilized in aerospace,national defense,and petrochemical industries due to their superior physical and chemical *** processing of bulk SiC ceramics necessitates precise and efficient grinding techniques to produce components with satisfactory ***,the inherent high hardness and brittleness of SiC ceramics present significant challenges during grinding,leading to severe brittle fracture and tool wear that compromise both surface integrity and production *** ductile-regime grinding of SiC ceramics can be achieved by enhancing machine tool accuracy and stiffness while optimizing wheel performance alongside appropriate selection of process parameters,a comprehensive summary of the mechanisms underlying damage evolution during grinding is lacking,and a mature grinding process for SiC ceramics has yet to be *** bridge this gap,the sintering technologies,mechanical properties,and microstructures of SiC ceramics were briefly *** grinding-induced damage mechanism and low-damage grinding technologies of SiC ceramics were *** fundamental science underlying the ductile deformation and removal mechanisms of brittle solids was ***,attention was directed towards the critical role of hybrid energy field grinding in minimizing brittle damages and promoting removal *** review not only elucidates the intrinsic interactions between the work material and abrasives,but also offers valuable insights for optimizing the grinding processes of brittle solids.

关键词： grinding damage evolution low damage high surface integrity silicon carbide ceramics

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Optimized Design of a Haptic Unit for Vibrotactile Amplitude Modulation

Optimized Design of a Haptic Unit for Vibrotactile Amplitude...

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IEEE International Conference on robotics and Biomimetics

作者： Jingchen Huang Yun Fang Weichao Guo Zhijian Qiao Xinjun Sheng State Key Laboratory of Mechanical System and Vibration School of Mechanical Engineering and the Meta Robotics Institute Shanghai Jiao Tong University Shanghai China Department of Electronic and Computer Engineering Hong Kong University of Science and Technology Hong Kong China

ISBN: (数字)9798331509644

ISBN: (纸本)9798331509651

Communicating information to users is a crucial aspect of human-machine interaction. Vibrotactile feedback encodes information into spatiotemporal vibrations, enabling users to perceive tactile sensations. It offers advantages such as lightweight, wearability, and high stability, with broad applications in sensory substitution, virtual reality, education, and healthcare. However, existing haptic unit designs lack amplitude modulation capabilities, which limits their applications. This paper proposed an optimized design of the haptic unit from the perspective of vibration amplitude modulation. A modified elastic model was developed to describe the propagation and attenuation mechanisms of vibration in the skin. Based on the model, two types of hierarchical architectural design were proposed. The design incorporated various materials arranged in multiple layers to amplify or attenuate the vibration amplitude as it traveled through the structure. An experimental platform was built to evaluate the performance of the optimized design.

关键词： Vibrations Solid modeling Virtual reality Amplitude modulation Robot sensing systems Motors Stability analysis Skin Haptic interfaces Spatiotemporal phenomena

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Programmable soft bending actuators with auxetic metamaterials

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Science China(Technological Sciences) 2020年第12期63卷 2518-2526页

作者： PAN Qi CHEN ShiTong CHEN FeiFei ZHU XiangYang Robotics Institute School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China

Soft robotics has been receiving increasing attention due to its flexibility and adaptability offered by embodied intelligence. A soft robot may undergo complex motions including stretching,contraction,bending,twisting,and their intricate *** these basic motions,bending plays a central role when a robot accomplishes tasks such as locomotion,grasping and manipulation. Although a rich repertoire of bending mechanisms has been reported,a systematic and rational design framework is still lack. In this paper,we provide a novel design strategy for soft bending actuators which allows integral modeling and design optimization. Nowadays,metamaterials are emerging as a new tool for soft robots,by encoding the desired complex motions directly within the material architectures,leading to conformable monolithic systems. We combine pneumatic actuators and flexible metamaterials to provide an alternative solution to soft bending actuators,with advantages of compact design,large bending motion,and convenient fabrication. A regular pneumatic chamber is embedded inside auxetic and non-auxetic metamaterials,and bending is generated when inflated. We carry out dimensionless analysis to identify the key design variables. To provide insight into design optimization,we develop a computation framework by modeling metamaterial structures with beam elements and the inner chamber with shell elements as an integral part,allowing efficient simulation of the coupled system. We systematically investigate how the bending angle varies with the key design variables and find the optimal design *** experimental results are well in line with the simulation,and a remarkable bending motion of 0.43°/mm is achieved.

关键词： soft robotics bending actuator auxetic metamterials negative Poisson’s ratio

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Operational-space wrench and acceleration capability analysis for multi-link cable-driven robots

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Science China(Technological Sciences) 2020年第10期63卷 2063-2072页

作者： SHENG XinJun TANG Lei HUANG XinJia ZHU LiMin ZHU XiangYang GU GuoYing Robotics Institute School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China

Multi-link cable-driven robots(MCDRs)have potential advantages in confined spaces exploration because of their redundancy and *** space wrench and acceleration capability analysis of MCDRs is important for their design,manipulability optimization,and motion ***,existing works mainly focus on capability analysis in the joint *** this paper,we present a zonotope-based iterative method and a simplified capability zonotope to analyze the operational-space wrench and acceleration capability of *** the iterative method,the capability generated by some cables can be iteratively added to the initial capability zonotope based on the Minkowski *** the simplified zonotope capability representation,a threshold is put forward to reduce redundant vertices and faces with little volume ***,simulations on a 24 DOFs MCDR are performed to verify the effectiveness of the developed *** results demonstrate that our iterative algorithm can easily generate the capability zonotope with a few MB ROM,while traditional operational wrench capability evaluation without our iterative algorithm needs 18432 GB ***,our simplified representation reduces the vertices and faces from 1260 and 2516 to 88 and 172,respectively,but with only 3.3%volume loss,which decreases the constraints of the robot and is conducive to manipulability optimization and motion planning.

关键词： multi-link cable-driven robots operational space capability analysis zonotope

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Confined spaces path following for cable-driven snake robots with prediction lookup and interpolation algorithms

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Science China(Technological Sciences) 2020年第2期63卷 255-264页

作者： TANG Lei ZHU LiMin ZHU XiangYang GU GuoYing Robotics Institute School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China

While cable-driven snake robots are promising in exploring confined spaces, their hyper-redundancy makes the collision-free motion planning difficult. In this paper, by combining the prediction lookup and interpolation algorithms, we present a new path following method for cable-driven snake robots to high-efficiently slither into complex terrains along a desired path. In our method, we first discretize the desired path into points, and develop the prediction lookup algorithm to efficiently find the points matched with joints of the robot. According to geometric relations between the prediction lookup results and link length of the robot, we develop the interpolation algorithm to reduce the tracking errors caused by the discretization. Finally, simulations and experiments of inspections in two confined spaces including the obstacle array and pipe tank system are performed on our custom-built 25 degree of freedoms(DOFs) cable-driven snake robot. The results demonstrate that the presented method can successfully navigate our snake robot into confined spaces with high computational efficiency and good accuracy, which well verifies effectiveness of our development.

关键词： cable-driven snake robot confined spaces path following prediction lookup interpolation

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Performance characterization of ionic-hydrogel based strain sensors

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Science China(Technological Sciences) 2020年第6期63卷 923-930页

作者： XU HaiPeng SHEN ZeQun GU GuoYing Robotics Institute School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China

Ionic hydrogels,owing to the advantages of stretchability,conductivity and transparency,have attracted more attention for developing new soft sensors and artificial *** works on ionic-hydrogel based sensors mostly focus on material synthesis,structure design and functional integration,while few studies investigate the characterization of their sensing *** this paper,we present a method to characterize the performance(e.g.,sensitivity,linearity and repeatability)of a kind of ionic-hydrogel based strain sensors by varying the testing frequencies and the sensors’geometry(e.g.,length-width(L/W)ratio).To this end,we first develop an experimental testing platform and fabricate a series of strain sensors made of the polyacrylamide(PAAm)hydrogel containing ionic conductive *** establish an equivalent electrical model to represent the ionic-hydrogel based strain sensors,indicating the influence of the testing frequencies and L/W ratio of the ionic hydrogels on their sensing *** theoretical predictions are in agreement with results obtained through experimental *** further demonstrate that(1)the sensitivity of the strain sensors,characterized by the gauge factor(GF),increases with the rise of testing frequencies but tends to be stable over the frequency of 5 kHz;(2)the sensitivity GF has a nonlinear relation with the L/W ratio of the strain sensors,but with a certain maximum value under the same testing frequency when the L/W ratio equals to *** verify the above experimental observations with two commonly used electrolytes,including lithium chloride and sodium *** the optimum testing frequency and L/W ratio,we finally conduct various experiments to demonstrate the low hysteresis and good repeatability of our ionic-hydrogel based strain *** work provides an approach to characterize the performance of the ionic-hydrogel based strain sensors,which may be an important step forward in further applicatio

关键词： ionic hydrogels sensor characterization large-strain sensor stretchable electronics

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Evaluation of surface integrity for ultra-precision machined fused silica surface based on atomic point-defect density

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Journal of Manufacturing Processes 2025年 149卷 917-930页

作者： Dinghuai Yang Linjie Zhao Jian Cheng Qi Liu Zixiao Zhang Hongqin Lei Zican Yang Henan Liu Jinghe Wang Yazhou Sun Mingjun Chen State Key Laboratory of Robotics and System School of Mechatronics Engineering Harbin Institute of Technology Harbin 150001 China Centre for Precision Manufacturing DMEM University of Strathclyde Glasgow G1 1XJ UK Center for Precision Engineering School of Mechatronics Engineering Harbin Institute of Technology Harbin 150001 China

The degree of plasticity and brittleness (DPB) of the material significantly affects the service performance of fused silica manufacturing surfaces in many frontier fields. However, there is still no effective method to quantitatively and non-destructively characterize their DPB, severely restricting the application of fused silica. Herein, atomic manufacturing-induced point defects on fused silica manufacturing surfaces were determined. Based on this, the evolution laws of various types of point defects with the DPB were discussed. Interestingly, it was found that the DPB is closely related to the densities of specific ODCII point defects, whose proportion ( k ) was chosen as the characteristic parameter to judge surface brittle fractures. Additionally, it was discovered that k sharply increased at the material brittle-plastic transition boundary, which was also verified based on the molecular dynamics simulation. Accordingly, whether k is >15 % was proposed as a criterion to judge whether the material has undergone brittle fractures during manufacturing processes. Furthermore, the significant increment of ODCII point defects was found to be the main cause of the obvious increment of k . Moreover, two causes of the significant increment of ODCII point defects were determined. Finally, the effectiveness of the judge criterion in six specific manufacturing cases was verified. Summarily, the study proposes a powerful nondestructive approach to judge the brittle fractures. It could quantitatively and non-destructively characterize the DPB during manufacturing processes. It is also applicable to the quantitative DPB characterization and the early warning detection of fracture breakdown for other brittle silicate materials.

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