共查询到20条相似文献,搜索用时 15 毫秒
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《Journal of sound and vibration》1987,115(3):473-482
An active suspension design to improve lateral ride quality and stability in a track/vehicle system subject to lateral track irregularity is presented. The measurement of the state variables is performed in a noisy environment, and unknown state variables of the system are estimated from the measurement data by using a Kalman filter. It is assumed that the lateral track irregularity and measurement noise are Gaussian random processes, respectively. The optimal control for the active suspension is determined by minimizing the quadratic performance index composed of the state variables and control efforts, and then the active suspension structure has a cascade feedback loop composed of the Kalman filter and the optimal controller. The numerical results indicate that the proposed active suspension provides much improved lateral ride quality and stability. 相似文献
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Optimal control of structures with semiactive-tuned mass dampers 总被引:1,自引:0,他引:1
U. Aldemir 《Journal of sound and vibration》2003,266(4):847-874
In this paper, the optimal performance of a magnetorheological (MR) damper which is used in a tuned mass damper in reducing the peak responses of a single-degree-of-freedom structure subjected to a broad class of seismic inputs including the harmonic, pulse, artificially generated and recorded earthquake excitations are studied. The optimal semiactive control strategy minimizes an integral norm of the main structure squared absolute accelerations subject to the constraint that the non-linear equations of motion are satisfied and is determined through a numerical solution to the Euler-Lagrange equations. The optimal performance evaluated for an MR damper is compared to an equivalent passive-tuned mass damper with optimized stiffness and damping coefficients. It is shown numerically that the optimal performance of the MR damper is always better than the equivalent passive-tuned mass damper for all the investigated cases and the MR damper has a great potential in suppressing structural vibrations over a wide range of seismic inputs. 相似文献
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为对物流车辆进行精准定位、检测和实时跟踪,需要物流车辆智能监控系统设计。当前使用的监控系统,在物流车辆进行运输的过程中,有遮挡物出现时无法精准的对物流车辆进行定位,当物流车辆停放在室内停车场时可能出现定位不到物流车辆的情况。为此,提出一种基于GPS的物流车辆智能监控系统设计方案。该系统硬件部分包括:GPS车载终端、监控中心服务器群和控制终端三部分,同时将全球定位系统与地理道路信息相结合,利用联通网络与国际互联网传输相关信息;系统软件部分使用联通分组通信技术,通过GIS软件与管理信息系统进行无缝连接,并由单片机S3C2440A向GPS模块发送控制中心下达指令,GPS接收指令并给予反馈,通过有效的分析反馈结果来提高监控终端的运行速度、稳定性以及精准度;GPS定位功能采用TDOA算法对物流车辆进行定位。实验证明,所提系统可以对物流车辆精准定位、实时监测和有效跟踪。 相似文献
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R. A. Musarskii 《Radiophysics and Quantum Electronics》1972,15(3):357-361
Methods of statistical dynamics are used to determine the values of the parameters of a vehicle suspension system which satisfy a general performance criterion. It is shown that the characteristic of the damping element must be essentially nonlinear in order to satisfy various motion conditions. A method for determining such a characteristic is given.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol.15, No. 3, pp. 474–479, March, 1972. 相似文献
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随着智能设备功能业务的逐渐扩展,用户对智能设备控制系统的实时性要求越来越高,当前控制系统采用CAN技术实现智能设备与用户间的通信,无法满足用户对系统实时性的需求。提出一种新的物联网嵌入式智能设备实时控制系统,通过构建系统的总体框架,将嵌入式LPC2378 ARM处理器作为核心处理器,通过RS-485总线将智能设备连接在一起,和处理器构成一个总线传输网络,在嵌入式LPC2378 ARM处理器中,将带DMA的10/100M以太网模块和以太网PHY芯片DP83848I连接,以提高数据包的传输效率,增强系统的实时性。系统GPRS模块选择SIM300CZ模块,将远程报警模块和RS-485总线结合在一起,共同实现远程报警和控制功能。软件设计时,给出了软件的整体架构和总体流程图,介绍了部分存储代码。实验结果表明,所设计系统对智能设备有很高的控制性能。 相似文献
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为了实现空调的智能控制,在分析空调控制系统不足的基础上,利用AT89S52单片机和GSM通信技术,设计了一款智能空调控制系统。设计了硬件系统和软件系统,该系统具备自动抽湿、补湿、净化室内空气和远程控制等功能。通过KEIL C软件编写、调试程序,并通过PROTUES进行仿真,验证了该设计方案的可行性。结果表明基于GSM的智能空调控制系统很好实现了自动抽湿、补湿、净化室内空气和GSM远程控制功能,具有较高社会应用价值。 相似文献
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发动机是混合动力电动汽车动力设备的心脏,为了保证混合动力电动汽车可以快速稳定地运行,需要对其转速智能控制系统进行设计。使用当前控制系统智能控制混合动力电动汽车发动机转速时,无法快速检测到发动机转速,难以达到最佳的智能控制结果。为此,本文提出一种基于软切换的Bang Bang-神经网络PID的混合动力电动汽车发动机转速智能控制系统设计方法。混合动力电动汽车发动机转速智能控制系统以Mcs一51系列8751单片机为核心系统,检测混合动力电动汽车发动机转速的数字信号,同时控制D/A模拟信号的输出,并在LED显示器上显示发动机转速数字信号,以PWM调制器放大混合动力电动汽车启动时发动机产生的PWM波,将放大后的PWM波供给电力发动机,再以分频填充脉冲装置测量混合动力电动汽车发动机转速,通过Bang Bang-神经网络PID算法计算出混合动力电动汽车发动机转速误差,达到实时控制混合动力电动汽车发动机转速的效果。实验仿真证明,所提设计方法保证了发动机转速的快速性和平稳性。 相似文献
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根据拓扑性质知觉原理,视觉原语是从整体到局部,拓扑感知优先。根据此仿生原理,建立感知目标物的形状拓扑信息的数学模型。首先提取物体三维轮廓信息;将空间图形轮廓降维映射到二维投影平面中进行处理;建立提取空间图形拓扑特征的数学模型。将轮廓拓扑空间同胚映射到(Hausdorf或度量空间或)二维投影平面,保持了拓扑不变性,因此便于分析出拓扑特征,可继续应用拓扑映射原理,分析点集拓扑。最终,拓扑特征与知识库模型相匹配,识别出物体。 相似文献
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串级二极管悬浮电极支撑控制系统主要包括支撑结构、驱动电路和同步控制三部分。支撑结构采用基于电磁铁工作原理的支撑针,对悬浮电极进行三点定位;驱动控制采用高压脉冲电容放电驱动螺线电磁铁,使电磁铁支撑针在5 ms内移动30 mm,悬浮电极在撤去支撑的5 ms内自由落体125 m;同步控制采用螺线电磁铁线圈信号作为同步控制初始信号,对该信号延时5 ms,触发闪光二号的前级触发源,启动闪光二号主机工作,实现螺线电磁铁与闪光二号主机的同步。使用该套支撑控制系统用于串级二极管前期研究,初步实现了两级间隙串联工作。 相似文献
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在信息化社会,智能建筑越来越多的被提及,智能建筑是指对建筑内外信息交换、舒适性、便利性和节能性的要求;建筑物室内湿度是人们在其中生活、工作、生产的重要考量因素;而随着技术发展,以高效稳定的FPGA芯片为核心的控制系统开始向智能建筑领域应用部署;因此文章提出并设计了基于FPGA的智能建筑湿度检测控制系统方案;文中采用硬件分析和软件设计相结合的方法;硬件分析需要对系统做一个整体把握并寻找经济实惠、稳定可靠的芯片,硬件的可靠是系统稳定工作的前提;软件设计需要将系统的工作方式和实际可能遇到的问题考虑进去,提高系统的容错能力;最后软硬结合并实验实践操作验证系统的可靠性;在实验结果中,该系统可以有效的调节室内的湿度并根据遇到的问题发出警告提示;得出结论,以FPGA控制器为核心的系统,可以担起智能建筑的湿度检测控制任务,并稳定工作。 相似文献
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为了更好的保证公路施工质量,保障施工人员的生命财产安全,建设平安和谐社会,为广大群众提供一个便利、舒适、安全地空间,需要对公路施工监控系统进行设计。当前的公路施工监控系统设计方法是利用图像处理板对其进行监控,监控过程中图像处理板的体积太大,没有设置隐蔽性屏障,导致监控盲点多,存在监控整体性能低,监控系统效果差的问题。为此,提出一种基于几何控制的公路施工智能监控系统设计方法。该方法首先确定公路施工监控类型,并对公路施工监控系统进行构造,然后以公路施工监控系统的构造为基础,利用编码感知路由,将各个终端监控的数据信息传输至监控系统中心,最后采用蛇形时隙数据存储算法将公路施工终端的监控信息数据全部存储,由此完成对公路施工的智能监控的系统设计。实验结果证明,所提方法可以对公路施工进行全方位,安全可靠地智能监控,减少了突发事件发生处理时间和监控盲点,增加了公路施工速度,更大程度地保障了施工人员的人身安全,为该领域的研究发展提供了强有力的依据。 相似文献
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This study develops a computational model of the dynamic characteristics of the actively controlled, magnetically levitated (maglev) system moving on a flexible guideway. The 5-dof (degree-of-freedom) vehicle model, the modeling of the EMS (electromagnetic suspension), guideway, and guideway irregularity are described, respectively. In this sense, the dynamic response of a coupled vehicle and guideway system is investigated with different vehicle speeds and masses. Furthermore, the formulation of SMC (sliding mode control) based on the Kalman filter is addressed for the control of the dynamic response of the maglev system for various prescribed running speeds. For numerical simulation, the Runge-Kutta method is used to solve the state-space equation, which includes information about the vehicle, guideway and controller. The results reveal that both the air gap fluctuation and the cabin CG (center of gravity) vertical acceleration are strongly affected by the vehicle speed and guideway irregularity, but only slightly affected by the vehicle mass. Moreover, SMC based on the Kalman filter considerably reduces the air gap fluctuation and cabin CG vertical acceleration responses, and the efficiency of the adopted control methodology is demonstrated even at higher critical speed conditions. 相似文献
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M.D. Rowbottom 《Journal of sound and vibration》1981,75(4):559-576
The use of mechanical dampers for the control of the self-excited galloping of transmission lines is considered. Two particular dampers, an in-span damper and a resilient mounting, are studied, two mass representations being used. For both dampers it is possible to produce an optimum damper either by maximizing the negative damping excitation that the damped system can withstand, or by choosing the smaller logarithmic decrement of oscillation of the system to be as large as possible in the absence of excitation. These two procedures do not produce the same damper parameters. Simple analytical expressions are produced for the optimum parameters, and these are shown to agree well with numerically optimized parameters. For the in-span damper, either method of optimization gives a damper for a much wider range of ratios of the damper to conductor masses than is predicted by earlier work. For the resilient mounting the optimization based on damping gives very similar behaviour to that of the in-span damper. When aerodynamic excitation is considered for the resilient mounting, a clear optimum exists only for a small range of mass ratios. Results from a representation of the conductor by a stretched string are used to define the range of mass ratios over which the two-mass damper idealizations may be used to define damper properties. 相似文献
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This paper presents a novel approach to the reduction of short-span bridge dynamic responses to heavy vehicle crossing events. The reductions are achieved through adjustment of the vehicle suspension damping coefficient just before the crossing. Given pre-calculations of the response of a vehicle-bridge system to a set of ‘unit’ road disturbances, it is shown that a single optimum damping coefficient may be determined for a given velocity and any specified road profile. This approach can facilitate implementation since the optimum damping is selected prior to the bridge and there is no need to continuously vary the damping coefficient during the crossing. The concept is numerically validated using a bridge-vehicle interaction model with several road profiles, both measured and artificially generated. The bridge-friendly damping control strategy is shown to reduce bridge dynamics across a typical range of vehicle velocities, proving most effective for road profiles that induce large vibrations in the vehicle-bridge system. 相似文献
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Fluid viscous dampers have been widely used for suppression of high velocity shocks. While linear fluid viscous dampers have been used for a long time, nonlinear fluid viscous dampers show considerable promise due to their superior energy dissipation characteristics and significant reduction in the damper force compared to a linear fluid viscous damper for the same peak displacement. This paper presents results from experimental study to characterize fluid viscous dampers when subjected to half-cycle sine shock excitation. The mathematical formulation and a numerical study to evaluate the relative performance of structures with fluid viscous dampers subjected to short-duration shock (impulse) loading are also discussed. The influence of damper nonlinearity (α) and the supplemental damping ratio (ξsd) on response has been investigated. The supplemental damping ratio of nonlinear fluid viscous dampers when subjected to shock excitation is found by equivalent linearization using the concept of equal energy dissipation. The paper also presents some design charts, which can be used for preliminary decisions on parameters of nonlinear dampers to be used in design. 相似文献