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Research on semi-active control method of a building structure based on non-smooth control

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Earthquake Engineering and Engineering Vibration 2019年第2期18卷 425-432页

作者： Wang Qing Wang Jianhui Ma Kemao School of Mechanical and Electric Engineering Guangzhou University School of Astronautics Harbin Institute of Technology

This study investigates the effectiveness of the non-smooth semi-active control algorithm on suppressing the vibration performance of a building structure subjected to seismic waves. According to the Lyapunov stability theory, it has bene proven that the non-smooth semi-active control algorithm can achieve a finite-time stability of the vibration relative to the isolation layer of a building structure. Through numerical simulation of two buildings with different parameters subjected to the input of a seismic wave, the vibration conditions of passive control, LQR semi-active control and non-smooth semiactive control are compared and analyzed. The simulation results show that the non-smooth semi-active control algorithm has a better robustness and effectiveness in restraining the impact of earthquakes on the structure.

关键词： building structure isolation layer semi-active control non-smooth control vibration

Ground target localization algorithm for semi-active laser terminalcorrection projectile

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Defence Technology（防务技术） 2016年第3期12卷 234-241页

作者： Xing-long LI Wen-jin YAO Li-kun ZHU Xiao-ming WANG Ji-yan YU School of Mechanical Engineering Nanjing University of Science and Technology Nanjing China Institute of Chemical Materials of CAEP Mianyang Sichuan 621900 China

A target localization algorithm,which uses the measurement information from onboard GPS and onboard laser detector to acquire the target position,is proposed to obtain the accurate position of ground target in real time in the trajectory correction process of semi-active laser terminal correction projectile.A target localization model is established according to projectile position,attitude and line-of-sight *** effects of measurement errors of projectile position,attitude and line-of-sight angle on localization accuracy at different quadrant elevation angles are analyzed through Monte-Carlo *** simulation results show that the measurement error of line-of-sight angle has the largest influence on the localization *** localization accuracy decreases with the increase in quadrant elevation ***,the maximum localization accuracy is less than 7 *** proposed algorithm meets the accuracy and real-time requirements of target localization.

关键词： semi-active laser guidance Terminal correction projectile Target localization Localization accuracy

Integrated intelligent control analysis on semi-active structures by using magnetorheological dampers

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Science China(Technological Sciences) 2008年第12期51卷 2270-2284页

作者： XU ZhaoDong1 & GUO YingQing2 1Civil Engineering College, Southeast University, Nanjing 210096, China 2 Automation College, Southeast University, Nanjing 210096, China Civil Engineering College Southeast University Nanjing 210096 China Automation College Southeast University Nanjing 210096 China

The control strategy is very important for semiactive control or active control systems. An integrated intelligent control strategy for building structures incorpo rated with magnetorheological (MR) dampers subjected to earthquake excitation is proposed. In this strategy, the time-delay problem is solved by a neural network and the control currents of the MR dampers are determined quickly by a fuzzy controller. Through a numerical example of a three-storey structure with one MR damper installed in the first floor, the seismic responses of the uncontrolled, the intelligently controlled, the passiveon controlled, and the passive-off controlled structures under different earthquake excitations are analyzed. Based on the numerical results, it can be found that the time domain and the frequency domain responses are reduced effectively when the MR damper is added in the structure, and the integrated intelligent control strategy has a better earthquake mitigation effect.

关键词： magnetorheological damper semi-active control intelligent

Improved ON-OFF semi-active Control Algorithm and Its Performance Simulation Analysis

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Journal of Donghua University(English Edition) 2018年第2期35卷 182-192页

作者： HUANG Dashan ZHANG Jinqiu LIU Yile Department of Equipment Training ＆ Testing Academy of Armored Force Engineering Beifing 100072 China

To improve the switching time of the control force in standard sky-hook ON-OFF semi-active control algorithm,a stateadjust coefficient was adopted in the improved ON-OFF( ION-OFF)algorithm. In considering of the riding comfort and the handling stability of vehicle, a comprehensive performance assessment criterion on suspension system was established with the utilization of the corresponding passive suspension system. Several simulations and analyses were conducted on improved ON-OFF semi-active suspension system with the comparison of passive suspension system and ON-OFF semi-active suspension system. The simulation results showed that the optimal comprehensive performance of the improved ON-OFF suspension system could be achieved when the state-adjust coefficient equalled 0. 6 as the vehicle running on C level road with the speed of 10 m/s,and the comprehensive performance was better than ON-OFF suspension system. Conclusions could be drawn from the frequency domain analysis that the performance of riding comfort and handling stability were both improved in the low resonance frequency and the mid-frequency range. The fact could be known that the comprehensive performance of the suspension system was associated with the frequency of the riding road and the sprung mass( SM) with the analysis of affecting factors.

关键词： suspension system control algorithm semi-active sky-hook control ON-OFF control

H_(∞)control in the frequency domain for a semi-active floor isolation system

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Frontiers of Structural and Civil Engineering 2013年第3期7卷 264-275页

作者： Yundong SHI Tracy C BECKER Masahiro KURATA Masayoshi NAKASHIMA Graduate School of Engineering Kyoto UniversityKyoto 611-0011Japan Disaster Prevention Research Institute Kyoto UniversityKyoto 611-0011Japan

A floor isolation system installed in a single floor or room in a fixed base structure is designed to protect *** this configuration,the input motions to the floor isolation from the ground motions are filtered by the structure,leaving the majority of the frequency content of the input motion lower than the predominant frequency of the *** floor isolation system should minimize the acceleration to protect equipment;however,displacement must also be limited to save floor space,especially with long period ***-active control with an H_(∞)control was adopted for the floor isolation system and a new input shaping filter was developed to account for the input motion characteristics and enhance the effectiveness of the H_(∞)control.A series of shake table tests for a semi-active floor isolation system using rolling pendulum isolators and a magnetic-rheological damper were performed to validate the H_(∞)*** control using an oil damper was also tested for *** test results show that the H_(∞)control effectively reduced acceleration for short period motions with frequencies close to the predominant frequency of the structure,as well as effectively reduced displacement for long period motions with frequencies close to the natural frequency of the floor isolation *** H_(∞)control algorithm proved to be more advantageous than passive control because of its capacity to adjust control strategies according to the different motion frequency characteristics.

关键词： semi-active floor isolation H1 control MR damper shaping filter shaking table test

Investigation of semi-active Hydro-Pneumatic Suspension for a Heavy Vehicle Based on Electro-Hydraulic Proportional Valve

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World Journal of Engineering and Technology 2017年第4期5卷 696-706页

作者： Wenchao Yue Shoucheng Li Xiaojun Zou NAVECO Ltd. Nanjing China School of Mechanical Engineering Nanjing University of Science and Technology Nanjing China

Hydro-pneumatic suspension is widely used in heavy vehicles due to its nonlinear characteristics of stiffness and damping. However, the conventional passive hydro-pneumatic suspension can’t adjust parameters according to the complicated road environment of heavy vehicles to fulfill the requirements of the vehicle ride comfort. In this paper, a semi-active hydro-pneumatic suspension system based on the electro-hydraulic proportional valve control is proposed, and fuzzy control is used as the control strategy to adjust the?damping force of the semi-active hydro-pneumatic suspension. A 1/4?semi-active hydro-pneumatic suspension model is established, which is co-simulated with AMESim and MATLAB/Simulink. The co-simulation results show that the semi-active hydro-pneumatic suspension system can significantly reduce vibration of the vehicle body, and improve the suspension performance comparing with passive hydro-pneumatic suspension.

关键词： Hydro-Pneumatic Suspension semi-active Control Co-Simulation Electro-Hydraulic Proportional Valve

The Echo Modelling and Simulation of the semi-active Radar Seeker against a Sea Skimming Target

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Journal of Computer and Communications 2018年第12期6卷 74-79页

作者： Peng Peng Lixin Guo Hualong Sun School of Physics and Optoelectronic Engineering Xidian University Xi’an China

This paper has proposed a new modelling and simulating technique for the echo of the semi-active radar seeker against the sea skimming target. The echo modelling is based on the electromagnetic scattering mechanisms. A modified Four-path model based on the radar detection scene is used to describe the multipath scattering between the target and rough sea surface. A Facet-based Small Slope Approximation (FBSSA) method is employed to calculate the scattering from the sea surface. The Physical Optics (PO) and the Equivalent Edge Current (EEC) Method is used to calculate the target scattering. In the echo simulations. The results present the original echo and the echo processed by the signal processing procedures, where the clutter and multipath effect can be observed.

关键词： semi-active Radar Seeker Sea Skimming Target Electromagnetic Scattering Radar Echo

Skyhook Surface Sliding Mode Control on semi-active Vehicle Suspension System for Ride Comfort Enhancement

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Engineering（科研） 2009年第1期1卷 23-32页

作者： Yi Chen Department of Mechanical Engineering University of Glasgow

A skyhook surface sliding mode control method was proposed and applied to the control on the semi-active vehicle suspension system for its ride comfort enhancement. A two degree of freedom dynamic model of a vehicle semi-active suspension system was given, which focused on the passenger’s ride comfort perform-ance. A simulation with the given initial conditions has been devised in MATLAB/SIMULINK. The simula-tion results were showing that there was an enhanced level of ride comfort for the vehicle semi-active sus-pension system with the skyhook surface sliding mode controller.

关键词： Sliding Mode Control Skyhook Damper Fuzzy Logic Control semi-active Suspension System

Attenuation Performance of a semi-active Helmholtz Resonator in a Grazing Flow Duct

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Open Journal of Acoustics 2013年第1期3卷 25-29页

作者： Xiaofeng Shi Cheuk Ming Mak Jun Yang Department of Building Services Engineering The Hong Kong Polytechnic University Hong Kong China Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Beijing China

Side branch Helmholtz resonators (HRs) are widely used to control low frequency tonal noise in air duct system. The passive Helmholtz resonator only works effectively over a narrow frequency range around resonance frequency. Changes in the exciting frequency and temperature will decrease the noise reduction performance. Many studies have been conducted on incorporating a Helmholtz resonator with active noise control to tuning the resonance frequency of HRs. The objective of this study is to study the effect of flow on the semi active Helmholtz resonator for duct noise control. Owing to a low Mach number air flow, the discontinuity condition at the joint is analytically formulated according to the conservation of the momentum and mass of air flow. Based on the transfer function at the junction, a controller function is proposed to tune the semi-active Helmholtz resonator under flow condition.

关键词： Helmholtz Resonator Flow Effect semi-active Control