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Double-Layered Microcracks Coupled Strain Sensors with High Sensitivity and Wide Working Range

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SSRN 2024年

作者： Wang, Zihao Liang, Cuiyuan Yang, Yuanhe Sun, Jiaxue Zhang, Xuelin Wang, Yu Jiang, Ying Liu, Yan Qi, Dianpeng MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage National and Local Joint Engineering Laboratory for Synthesis Transformation and Separation of Extreme Environmental Nutrients School of Chemistry and Chemical Engineering Harbin Institute of Technology Harbin150001 China Key Laboratory of Science and Engineering for the Multi-modal Prevention and Control of Major Chronic Diseases Ministry of Industry and Information Technology Zhengzhou Research Institute Harbin Institute of Technology Zhengzhou450000 China School of Astronautics Harbin Institute of Technology Harbin150001 China Department of Electromechanical Engineering Centre for Artificial Intelligence and Robotics University of Macau 999078 China

The flexible strain sensor is a crucial component of the wearable technology, offering considerable potential for monitoring physiological signals. Notably, strain sensors based on nanomaterial thin films have gained much attention from researchers due to their excellent performance and ease of preparation. Nevertheless, challenges remain, such as the rapid expansion of cracks in rigid conductive films under strain, which greatly reduces the working range of the sensors. Conversely, soft conductive films characterized by small cracks are much less sensitive. This study introduces a novel conductive strategy centered on the double-layered microcracks of gold/PPy (Polypyrrole) composite films. The as-prepared strain sensor exhibits ultra-high sensitivity with a gauge factor (GF) of approximately 3.604 × 107, an expansive working range spanning from 0% to 60%, high strain resolution at 0.1% and commendable cycling stability exceeding 1000 cycles. The crack formation and sensing mechanisms were thoroughly investigated, elucidating the key role of the double-layered microcracks in enhancing sensing performance. Ultimately, the practicality of the developed sensor for human health monitoring and human-computer interaction was demonstrated by the accurate detection of human motion. © 2024, The Authors. All rights reserved.

关键词： Thin films

Modeling and Analysis of a Non-linear Electret Electrostatic Energy Harvester

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Modeling and Analysis of a Non-linear Electret Electrostatic...

IEEE International Conference on Automation, Electronics and Electrical Engineering (AUTEEE)

作者： Shaohua Niu Chunhui Gao Jian Chen Science and Technology on Electromechanical Dynamic Control Laboratory Beijing Institute of Technology Beijing China Beijing Power Machinery Institute Beijing China

ISBN: (数字)9781728198279

ISBN: (纸本)9781728181585

With the rapid development of MEMS and CMOS sensors and improvement of data processing capabilities we have entered the era of the internet of everything (IoE), and the ensuing problem of sensor power supply has attracted more and more people's attention. Vibration energy harvester that can directly convert vibration energy into electrical energy from the environment have become hot topics in recent years because of the short life, large size, long-term storage and other shortcomings of traditional chemical batteries. The electrostatic vibration energy harvester is a typical harvester, which always uses beam structure to capture the environmental energy. However the working bandwidth of traditional beam is always relatively narrow, while the vibration frequency range of environment is relatively wide. Thus the capture energy efficiency of traditional beam structure is relatively low. In this paper, a nonlinear method is introduced into electret electrostatic energy harvester, which employed magnetic body structure to introduce nonlinear force. In the paper, the model of this nonlinear harvest is built, and its characteristics are analyzed. According the analysis result, magnetic force introduced can improve capture energy bandwidth, moreover, repulsive force expands the bandwidth larger than attractive force.

关键词： Vibrations Force Electrets Magnetic forces Magnetic resonance Magnetoelasticity Electrostatics

Self-powered wireless impedance sensing for structural health monitoring

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Self-powered wireless impedance sensing for structural healt...

2019 IEEE International Conference on Unmanned Systems, ICUS 2019

作者： Feng, Yue Tang, Xusong Shao, Bohan Han, Yanhui Beijing Institute of Technology Science and Technology on Electromechanical Dynamic Control Laboratory Beijing China Beijing Orient Institute of Measurement Test Beijing China

ISBN: (纸本)9781728137926

Structural damage is often accompanied by equipment failures and safety incidents. For example, aircraft accidents often result from wing breaks and landing gear damage. The self-powered wireless sensing technology is ideal tool for monitoring structural health in multi-locations. In this work, we designed an airflow-driven energy harvester (EH) and integrate into wireless impedance sensing system. Also, the Energy Management and control Circuit (EMC) is designed to provide a stable DC voltage for intermittently driven sensing system. The experimental results show that the self-powered impedance sensing system can operate at every 3 min at a wind speed of 8 m/s. The system error is within 5% compared to the Agilent 4294A (Precision Impedance Analyzer) and the characteristics of the material cracks could be successfully detected and analyzed. © 2019 IEEE.

关键词： Energy harvesting

Density-Functional Theory Study of Snse/Gese Heterostructure for Gaseous Sulfur Hexafluoride Decomposition Products Sensing

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SSRN 2024年

作者： Shi, Yijie Hao, Jiongyue Dong, Yingchun Guo, Xuezheng Liang, Chengyao Kibet, Evans He, Yuhui Ge, Liang Gao, Chao Miao, Xiangshui Meng, Gang He, Yong Key Laboratory of Optoelectronic Technology and Systems The Education Ministry of China College of Optoelectronic Engineering Chongqing University Chongqing400044 China State Key Laboratory of Coal Mine Disaster Dynamic and Control Chongqing University Chongqing400044 China School of Integrated Circuits Huazhong University of Science and Technology Wuhan430074 China College of Mechanical and Electronic Engineering Southwest Petroleum University Chengdu610500 China Key Laboratory of Photovoltaic and Energy Conservation Materials Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences Hefei230031 China

Partial discharge and local overheating will lead to the decomposition of superior dielectric gas sulfur hexafluoride (SF6) used in gas insulated substations (GIS). Detecting SF6 decomposition gases by gas sensors to diagnose early latent insulation failures is a potential approach to guarantee safety and reliability of GIS. However, the main difficulties lie in sensitivity, operating temperature and sulfur poisoning of the sensor. Metal oxide semiconductor-based gas sensors suffer from high working temperature and sulfur poisoning. Two-dimensional selenides have shown the potential of room temperature gas sensing. Compared with pristine materials, heterostructures usually have narrower band gaps and higher carrier mobility, which promise sensitivity. In this work, a SnSe/GeSe van der Waals heterostructure model is constructed to investigate the gas sensing properties by density functional theory calculations. The SnSe/GeSe heterostructure exhibits huge adsorption energy and comparatively large charge transfer to the SF6 decomposition gases. The calculation results suggest that the excellent sensing properties are contributed to the synergistic effect between the SnSe and the GeSe layers. Besides, the physical adsorption avoids sulfur poisoning of the material. This study provides theoretical bases for the repeatable detection of SF6 decomposition products by SnSe/GeSe heterostructure and its potential in the design of electronic noses. © 2024, The Authors. All rights reserved.

关键词： Density functional theory

A Reinforcement Learning-Based Energy Management Strategy for Fuel Cell Electric Vehicle Considering Coupled-Energy Sources Degradations

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SSRN 2022年

作者： Huo, Weiwei Liu, Teng Li, Fajia Institute of Electromechanical Engineering Beijing Information Science & Technology University Beijing100192 China Collaborative Innovation Center of Electric Vehicles in Beijing Beijing Information Science & Technology University Beijing100192 China Key Laboratory of Modern Measurement and Control Technology Ministry of Education Beijing Information Science and Technology University Beijing100192 China University of Jinan Jinan250024 China

The energy management strategy (EMS) is crucial for fuel cell electric vehicles (FCEV) by decreasing the equivalent fuel consumption and postponing fuel cell deterioration. An improved EMS based on the Twin Delayed Deep Deterministic Policy Gradient (TD3) deep reinforcement learning considering energy sources degradation and economic factor is proposed in this paper. The working condition identification (WCI) implemented by ensemble bagged trees (EBT) is used to expand the diversity of EMS application scenarios . The drastic loading change of fuel cell is avoided for minimizing the instantaneous cost (MIC), which reduces fuel cell degradation greatly. TD3 is applied to optimize the total cost combined with WCI and MIC. The training results based on 13 classic working conditions show that the degradation of the fuel cell system is effectively suppressed, decreasing the overall cost and accelerating the algorithm's convergence time significantly. © 2022, The Authors. All rights reserved.

关键词： Energy management

Weak wide-band signal detection method based on small-scale periodic state of Duffing oscillator

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Chinese Physics B 2018年第3期27卷 205-215页

作者： Jian Hou Xiao-peng Yan Ping Li Xin-hong Hao Science and Technology on Electromechanical Dynamic Control Laboratory School of Mechatronical Engineering Beijing Institute of Technology Beijing 100081 China

The conventional Duffing oscillator weak signal detection method, which is based on a strong reference signal, has inherent deficiencies. To address these issues, the characteristics of the Duffing oscillator＇s phase trajectory in a small- scale periodic state are analyzed by introducing the theory of stopping oscillation system. Based on this approach, a novel Duffing oscillator weak wide-band signal detection method is proposed. In this novel method, the reference signal is discarded, and the to-be-detected signal is directly used as a driving force. By calculating the cosine function of a phase space angle, a single Duffing oscillator can be used for weak wide-band signal detection instead of an array of uncoupled Duffing oscillators. Simulation results indicate that, compared with the conventional Duffing oscillator detection method, this approach performs better in frequency detection intervals, and reduces the signal-to-noise ratio detection threshold, while improving the real-time performance of the system.

关键词： Duffing oscillator weak signal detection stopping oscillation system small-scale periodic state

Research on the Thermal Comfort of Passenger Compartment Based on the Pmv/Ppd

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SSRN 2022年

作者： Huo, Weiwei Cheng, Yaxian Jia, Yunxu Guo, Chendong Institute of Electromechanical Engineering Beijing Information Science and Technology University 12 Xiaoying East Road Qinghe Haidian District Beijing100192 China Collaborative Innovation Center of Electric Vehicles in Beijing Beijing Information Science & Technology University Beijing100192 China Key Laboratory of Modern Measurement and Control Technology Ministry of Education Beijing Information Science and Technology University Beijing100192 China

With the increasing requirements of consumers for vehicle performance, the thermal comfort has become a key index of consumers. The thermal environment inside the passenger compartment directly determines the thermal comfort of vehicle. However, few researchers focused on the effect of the external thermal environment on the internal thermal flow field of a vehicle. In this paper, the thermal comfort of the passenger compartment is analyzed based on Computational Fluid dynamics. The transient response of the thermal environment of passenger compartment is investigated, and the thermal comfort of the passenger compartment is evaluated based on the PMV/PPD (Predicted Mean Vote/Predicted Percentage Dissatisfied) evaluation index. The changes in the thermal flow field in the vehicle are analyzed for the three cases of 0°, 30° and 60° air supply angles of the air conditioning system, and the effect of the field synergy angle size on the distribution of the flow field in the passenger compartment is analyzed in conjunction with the principle of enhanced heat transfer by field synergy. The results showed that the smaller the field synergy angle, the stronger the heat transfer performance. And the best overall thermal comfort in the passenger compartment at an air supply angle of 30°. © 2022, The Authors. All rights reserved.

关键词： Flow fields

Sliding Mode Observation and control for Overhead Cranes with Varying Rope Length

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Sliding Mode Observation and Control for Overhead Cranes wit...

2021 China Automation Congress, CAC 2021

作者： Huan, Xuwei Niu, Dan Li, Qi Yang, Jun Liu, Guoyao Chen, Xisong Xiao, Xi Key Laboratory of Measurement and Control of CSE Ministry of Education Southeast University Nanjing China Department of Aeronautical and Automotive Engineering Loughborough University LoughboroughLE11 3TU United Kingdom Nanjing Sciyon Automation Group Co. Ltd Nanjing China Aviation Key Laboratory of Science and Technology on Aero Electromechanical System Integration Nanjing China

ISBN: (纸本)9781665426473

This paper proposes a state observer and controller based on the second-order sliding mode scheme for underactuated overhead cranes with load hoisting and lowering. The designed state observer can effectively estimate the uncertainly and unmodeled dynamics of crane systems, and provide appropriate driving force compensations for the sliding mode controller designed by coupling the load swing angle. This guarantees an accurate load positioning and residual swing elimination. Based on the Lyapunov stability criterion, the asymptotic stability of the control system is proved Several simulations are implemented to verify the effectiveness and robustness of the proposed controller for anti-sway and positioning controls. © 2021 IEEE

关键词： Asymptotic stability

Neural dynamic Surface Containment control for Multiple Quadrotors

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Neural Dynamic Surface Containment Control for Multiple Quad...

2019 IEEE International Conference on Unmanned Systems, ICUS 2019

作者： Shao, Xingling Tian, Biao Li, Dongguang Ministry of Education North University of China School of Instrument and Electronics North University of China Key Laboratory of Instrumentation Science Dynamic Measurement Taiyuan030051 China Beijing Institute of Technology Science and Technology on Electromechanical Dynamic Control Laboratory Beijing10081 China

ISBN: (纸本)9781728137926

This paper presents an neural dynamic surface containment control design for multiple quadrotors with uncertainties, such that the followers can be driven into the convex hull constituted by multiple dynamic leaders. To facilitate the control design, the quadrotor dynamics is decomposed into translational and rotational subsystems. For each subsystem, in order to enable smooth and rapid learning of unknown system uncertainties and reduce the computational load in traditional neural network (NN), the estimation errors, instead of tracking errors, are used to regulate NN weights and only one NN learning parameter is required for adaptive neural approximation with the aid of minimal learning parameter (MLP), which is more feasible for real-time implementation. Additionally, dynamic surface control (DSC) technique is introduced to extract the time derivative of virtual control laws, and thus the issue of "explosion of complexity" can be circumvented. Finally, the stability analysis is established. Simulation results illustrate the effectiveness and superiority of the proposed control scheme. © 2019 IEEE.

关键词： Real time control