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International Conference on Microwave and Millimeter Wave technology Proceedings

作者： Yiming Wang Wentao Li Xiaowei Shi Science and Technology on Electromechanical Dynamic Control Laboratory China School of Electronic Engineering Xidian University Xi’an China

ISBN: (数字)9781728157337

ISBN: (纸本)9781728157344

Radio fuze devices are used to detect the location of targets on the battlefield. With the continuous development of electronic technology, their ability to resist external interference has received increasing attention. In this letter, a reconfigurable pixel antenna working in the C-band is proposed. The antenna consists of a driving patch and a parasitic pixel surface that is divided into two layers, the inner and outer layers. By changing the connection of the inner and outer pixel surfaces, the antenna's operating frequency, polarization, and radiation pattern can be controlled in real time, the reconfigurable performance of two frequency and polarization states and three pattern modes for each operating state are obtained. Both operating states are in the C-band, and the antenna gain is about 5dB and 4dB, respectively. This antenna can be used in anti-jamming fuze. Compared with the traditional microstrip fuze antenna, the designed antenna is suitable for more working scenarios, and the flexible reconfigurable performance is more conducive to the realization of anti-jamming performance.

关键词： Microwave antennas Time-frequency analysis Microstrip antennas Resists Real-time systems Frequency control Antenna radiation patterns

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Six-dimensional ballistics of a certain howitzer projectile considered with dynamic unbalance 31

Six-dimensional ballistics of a certain howitzer projectile ...

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31st International Symposium on Ballistics, BALLISTICS 2019

作者： Zhang, Zhibiao Meng, Cheng Wang, Yushi Science and Technology on Electromechanical Dynamic Control Laboratory China School of Mechanical Engineering Nanjing University of Science and Technology Jiangsu Nanjing210094 China

ISBN: (纸本)9781605956107

The fabrication error and assembly error of warhead and fuse will cause the dynamicunbalance of howitzer projectile, which will bring a negative impact on the safety andreliability of fuse. In order to obtain the motion of a certain 155 mm howitzer projectile onthe exterior ballistics, the six-dimensional rigid body motion equations of the projectile werestudied. The aerodynamic parameters which needed for the six-dimensional rigid bodymotion equations of the projectile's exterior ballistics need to be obtained by ***, the credibility of the simulation method is verified in this paper. Then theaerodynamic parameters of the projectile are obtained by numerical simulation of theprojectile flow field. When solving the six-dimensional rigid body motion equations ofprojectile exterior ballistics, the dynamic unbalance of projectile is considered. Thecalculation results are very important for the safety and reliability of fuze on the projectileunder the condition of dynamic unbalance. © 2019 by International Ballistics Society All rights reserved.

关键词： Projectiles

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

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

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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

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Self-powered wireless impedance sensing for structural health monitoring

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

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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

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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

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Measuring System Of Internal Charges In Electron Irradiated Spacecraft’s Insulating Medium

Measuring System Of Internal Charges In Electron Irradiated ...

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IEEE International Conference on Unmanned Systems (ICUS)

作者： Yue Feng Xusong Tang Yanhui Han Science and Technology on Electromechanical Dynamic Control Laboratory School of Mechatronical Engineering Beijing Institute of Technology Beijing China Beijing Orient Institute of Measurement& Test Beijing China

ISBN: (数字)9781728180250

ISBN: (纸本)9781728180267

The accumulation of internal charge in the insulating medium caused by the high-energy charged particles has been one of the important factors threatening the safety of spacecrafts. As the spacecraft's orbital flight time and flight height increase, the internally charged effect of its insulating medium becomes more and more serious. In this work, we designed an internal charge distribution measuring system for an insulating medium under electron irradiation, based on the acoustic pulse method. The system could measure the internal charge of the dielectric material without contacting between the sample and the excitation unit. Furthermore, the internal charge measurements were performed on three kinds of typical spacecraft insulation medium materials (polyimide (PI), low-density polyethylene (LDPE), and polytetrafluoroethylene (PTFE)) under electron irradiation. The internal charge and internal electric field distribution of the specimens were obtained. This system is more suitable for studying the internal charge accumulation behavior of spacecraft's insulating medium in space environment.

关键词： Radiation effects Polyimides Polyethylene Data processing Charge measurement

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Neural dynamic Surface Containment control for Multiple Quadrotors

Neural Dynamic Surface Containment Control for Multiple Quad...

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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

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Dome-shaped tactile sensor for detecting object stiffness and potential

Dome-shaped tactile sensor for detecting object stiffness an...

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IEEE International Conference on Unmanned Systems (ICUS)

作者： Yue Feng Kehang Zhong Zhilong Zhou Yanhui Han Science and Tehnology on Electromechanical Dynamic Control Labortary School of Mechatronical Engineering Beijing Institute of Technology Beijing China Beijing Orient Insititute of Measurement and Test Beijing China

ISBN: (数字)9781728180250

ISBN: (纸本)9781728180267

Multi-functional tactile sensors, capable of measuring multi-physical quantities in a limited space by one structure, have aroused great research interest. This paper proposes a monostable dome-shaped sensor for the simultaneous measurement of the stiffness and surface potential of the object at the same position. In the proposed sensor, the top electrode is a flexible spherical stainless steel dome, and the bottom electrode is a circular sheet covered with an electret film, providing a bias electric field. Output Voltages between two electrodes are generated because of the electrostatic effect, and resulting waveforms can be measured as the proposed sensor contacts and releases the object. While the proposed sensor approaches the object, the surface potential of the object determines the voltage waveform. After contacting the object, the voltage waveform indicates a direct comparison of stiffness between the object and top electrode, based on the monostable buckling of the dome. Here, we present theoretical and experimental relationships between measured voltages obtained from the proposed sensor and a charged electret film on the surface of the object. The proposed sensor makes it possible to measure the stiffness and surface potential of the object using voltage waveforms.

关键词： TV Radio frequency Erbium

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Magnetic Spring and Its Application in Fuze

Magnetic Spring and Its Application in Fuze

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Artificial Intelligence and electromechanical Automation (AIEA), International Conference on

作者： Haoyuan Yu Li Sui Xinyuan Bian Qiaoran Zhao School of Mechatronical Engineering Beijing Institute of Technology Beijing China Science and Technology on Electromechanical Dynamic Control Laboratory Beijing Institute of Technology Beijing China Reactor Engineering Technology Research Department Chinese Academy of Atomic Energy Beijing China

ISBN: (数字)9781728182889

ISBN: (纸本)9781728182896

During the working process of the fuze insurance institution, the metal coil spring as a resistance element may cause failure due to fatigue fracture and stress creep relaxation, thereby affecting the reliability and stability of the fuze safety system. To solve this problem, a kind of variable stiffness spring with negative stiffness characteristic is proposed in this paper, which is composed of two magnets. This spring has the advantages of simple structure and rich stiffness characteristics. It is used in fuze recoil insurance institutions to meet the requirements of fuze security system service handling security and reliable release of insurance at launch, providing new features for improving the performance of fuze insurance institutions Technical approach.

关键词： magnetic spring moving magnet steady state safety moving magnet resistive element insurance Steady state safety springs Device Spring Spring season institutions Fatigue fracture simple structures

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Theoretical analysis and experimental study of a perforated piezoelectric cantilever

Theoretical analysis and experimental study of a perforated ...

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第二届先进电子材料、计算机与材料工程国际学术会议（AEMCME 2019）

作者： Huaiwei Su Li Sui Ping Song Yousong Lu School of Mechatronical Engineering Beijing Institute of Technology Science and Technology on Electromechanical Dynamic Control Laboratory

Piezoelectric energy harvesters have been studied extensively because they show considerable promise for use in both military and commercial applications. In order to improve the output capability of the piezoelectric energy harvester, the perforated piezoelectric cantilevers were designed in this work. To study how the hole on the cantilever affected the output characteristics, this paper analysed the position and size of the hole separately. The results show that, perforating the cantilever can cause stress concentration of the piezoelectric cantilever, and improve the output capacity.

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