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1.
基于AVR单片机的门禁控制器的设计与实现   总被引:1,自引:0,他引:1  
介绍了一种基于ATmega16单片机控制的门禁控制系统的硬件和软件设计方法,该系统以直流电机为执行器;系统首先对光电编码器的脉冲信号进行采样,经ATmega16单片机中PID算法处理后产生PWM信号驱动直流电机,以此实现对控制门禁的开关时序和转速的调节控制:同时又有外连设备可供用户根据实际需要来改变系统参数,达到最合理配置;实验结果表明,该方法可以在生产中推广应用.  相似文献   

2.
为了提高电子商品防盗窃检测装置(Electronic Article Surveillance,简称EAS)中的同步发射信号的质量和抗干扰能力。在分析信号同步实现方法及电磁干扰问题的基础上,提出了一种使用光纤取代传统电缆传输同步信号的方法,并设计出实际电路。实际测试表明,光纤同步法具有很高的信号稳定度和极低的信号衰减率。  相似文献   

3.
为了解决隔爆低频(TBD)型永磁同步电动机(PMSM)中如何利用精确的转子位置和速度信号去实现磁场定向的问题,分析了永磁同步电动机的矢量控制理论,讨论了无传感器矢量控制方案,提出了基于空间电压矢量脉宽调制(SVPWM)技术的矢量控制方案,采用TMS320LF2812为核心处理器进行矢量控制系统的硬件设计,采用DSP编程实现该系统的软件设计,进行了基于无传感器矢量控制系统的仿真研究及实验波形分析。结果表明:无传感器矢量控制方案具有很好的动态特性,能够稳定运行,满足驱动系统的要求。  相似文献   

4.
组合控制是一种优化安全管理模式,其系统是众多控制系统中的一种,原理如图1所示。图中,A为给定元件,B为调节元件,C为执行元件,O为被控对象,Y为输出,D为干扰信号,ε为比较器。该控制系统的特点是:它是一个前馈-后馈互补控制系统,既能通过反馈补偿由于干扰信号而产生的偏差,又能通过反馈纠正实施过程中产生的偏差。因此,该系统控制稳定,给定元件的信号基本上能准确无误地传递到被控对象,形成给定的输出。  相似文献   

5.
为了探究城市道路交通安全风险的动态控制方法,应用道路交通安全风险、系统控制和管理控制等理论,构建城市道路交通安全综合风险控制系统。在此基础上,应用反馈系统理论与方法,研究该系统的基本组成、预警反馈控制基本原理、控制流程及控制运行管理体系。结果表明:城市道路交通安全综合风险控制系统的预警反馈控制机制由4个基本功能单元组成,系统预警控制运行管理体系具有4个层级;通过构建城市道路交通安全综合风险控制系统,应用系统综合风险动态评价、偏差报警等技术,能够建立系统跟踪反馈预警机制;借助系统预警控制运行管理体系,能够实现对风险的系统动态控制。  相似文献   

6.
流动式起重机的起升操作有以下具体要求:(1)起重机司机在进行起升作业时,应严格做到"十不吊"。即:指挥信号不明或违章指挥不吊;吊物超载不吊;工件捆绑的不牢不吊;吊物上面有人不吊;设备的安全装置不灵不吊;工件埋在地下不吊;作业场所光线阴暗视线不清不吊;有棱角的物件无防护措施不吊;斜拉工件不吊;作业时有6级以上强风不吊。(2)检查起重机滑轮倍率是否合适,配重状态与制动器的功能。倍率改变后的滑轮组须保持吊钩旋转轴与地面垂直。  相似文献   

7.
高端出入口控制产品是用于网络操作,为终端用户提供机会来集成入侵探测、视频监控、人力资源软件、建筑物控制、HVAC和火灾探测/救生的系统。集成安全系统为需要在多个系统之间进行通信的末端用户提供一种综合方法。在安装网络出入口控制系统之前必须考虑许多变量。  相似文献   

8.
针对扶梯运行参数常用检测方法及仪器存在误差大、操作复杂、效率低的不足,提出了一种快速精确的检测方法。首先通过一个可快速安装拆卸的信号采集模块对扶梯的梯级速度、扶手带速度、制停距离和减速度进行采集,结合制停同步触发信号,再对采集的脉冲信号进行处理和计算,实现了扶梯和人行道运行参数的快速精确检测。  相似文献   

9.
应用传感器和无线电技术,提出了一种有毒气体泄漏无线报警及控制系统的设计方案。该系统采用半导体气敏传感器QM-N10来检测有毒气体,通过检测电路把有毒气体浓度的变化转换为相应的电压信号,一旦超过设定的有毒气体的安全浓度值,系统启动发射电路工作。接收处理电路接收和处理发射电路发送的无线编码信号,同时输出控制信号启动扬声器报警,提醒工作人员采取安全防护措施。  相似文献   

10.
起重机发生断绳、塌梁、倾翻等事故,大多是因吊物时横拉斜拽和超载造成的。为了防止这类事故,我们根据GB6067—85标准的规定,研制了压磁式起重机超载保护装置。 这种保护装置(起重量限制器)由两部分组成,即起重量的检测部分(压磁式测力传感器)和二次控制仪表部分。它是通过压磁式测力传感器检测出实际起重量,经二次仪表放大处理后与额定量进行比较。当实际起重量达到额定量的90%时,二次仪表发出间歇的声光预警信号;当实际起重量达到额定量的105%时,二次控制仪表发出报警信号,同时切断起重机提升回路的电源,使吊载物只能下降而不能提升。 压…  相似文献   

11.
During the detection of pipeline leakages, false alarms of leak detection could be markedly reduced if the interference signals resulting from pressure regulating, pump regulating or valve movements could be accurately distinguished. A digital recognition method for interference signals and leakage signals based on a dual-sensor system is proposed in this paper. It is demonstrated that the direction of the signal can be recognized by a cross-correlation calculation between two signals from the dual-sensor, one of which undergoes forward linear interpolation and backward linear interpolation. Based on this theory, the interference signal and the leak signal can be discriminated exactly, and the distance between the two sensors in the dual-sensor system can be considerably reduced without needing to increase the sampling frequency. The monotonicity of the cross-correlation function is demonstrated, and a fast discrimination algorithm based on a binary extreme search method, which decreases the computational load and maintains global optimization, is also proposed. A pre-processing method of the actual signal is proposed to decrease the identity requirement for the two sensors in a dual-sensor system. In the experiment based on artificial signals, the proposed discrimination algorithm could achieve accurate recognition of the abnormal signal, and as such, the theory and application of pipeline leak detection based on dual-sensor systems are extended.  相似文献   

12.
设计一种基于微试剂原位水质检测仪的多参数水质微型站监控系统。通过对水质检测流程合理分析以及各监控点反馈信号诊断,结合LabVIEW可视化编程技术、信号分析技术和测控技术,分别从硬件和软件方面,设计了一种基于多传感器数据融合的水质微型站监控感知的检测流程测控模型。现场应用结果表明,采用诊断专家系统的水质微型站监控系统满足水质测控的需求,极大提升系统的稳定性、安全性。  相似文献   

13.
为了有效检测环空保护液位,评估气井环空带压情况,在传统回声法检测的基础上,提出了基于频谱分析及自相关分析的2种液位检测方法;搭建了液位检测试验系统,开展了不同环空压力下的液位检测试验,计算了不同压力下的环空声速;设计了FIR低通滤波器对液面回波信号进行滤波处理,同时利用了上述2种方法计算液位值并与实际值及传统液位计算方法对比,得出了声衰减系数并评判了衰减过程对液面回波信号频谱分析的影响程度。研究结果表明:设计的FIR低通滤波器适用于所建液位检测试验的滤波处理过程;频谱分析及自相关分析都能够有效检测液位高度,最大误差分别为1.65%和0.61%,自相关分析方法具有更高的精确度;声衰减系数整体较小,对液面回波信号频谱分析结果影响较小。  相似文献   

14.
As a method to prevent or mitigate cone discharges in a specific section such as a large silo, we have developed a new feedback control-type ionizer system. The feedback control-type system is composed mainly of an ionizer, an electrostatic field strength meter, and computer control equipment. In this study, we evaluated experimentally the practical version of the feedback control-type ionizer system through several tests in a pneumatic powder transport facility. The specific charges of the falling pellets in the silo were also measured for 10 s using a Faraday cage. Polypropylene (PP) pellets with a mean particle size of 3 mm were used in this experiment. The results of the experiment revealed that the feedback control-type ionizer system had the following characteristics: (1) it is possible to control the performance of the ionizer with a supply current; (2) the electrostatic field strength in the loading pipe from the charged powder is reduced and maintained at near zero by using the feedback control-type system; and (3) the performance of the feedback control-type system is superior to that of others, such as the conventional AC- or DC-type ionizers.  相似文献   

15.
高速公路紧急救援决策支持系统的设计   总被引:1,自引:8,他引:1  
以高速公路紧急救援管理现状为基础,阐述高速公路路网紧急救援决策支持系统的新需求;应用面向过程的方法,设计满足新需求的系统的总体结构、服务功能、数据流图和软件开发支撑环境;将智能交通系统中视频检测、优化调度、智能控制、GPS定位与导航等新技术与系统服务功能相结合,探讨了应用紧急事件检测、交通事故确认、紧急救援调度与交通管制、行程时间预测和最佳救援路径计算等相关的实施方案。应用Web-GIS和B/S网络结构技术研发应用软件,实现了区域路网各个紧急救援职能部门的信息共享和交通紧急救援决策支持的区域性管理。  相似文献   

16.
Gas leakage from pipeline leads to significant environmental damages and industrial hazards, so small leakage detection for gas pipeline is essential to avoid these serious leakages. However, because of the high frequency component of leakage signal attenuates quickly, traditional detection method which inspects pressure or vibration signal has problem to get effective information from leakage signal. So, a novel detection method based on acoustic wave is proposed. This paper, firstly, researches on the phonation principle of pipeline leakage and the characteristic of sound source, and simulates the leakage acoustic field on the basis of aero acoustics. Secondly, using Wavelet Packet Transform method and Fuzzy Support Vector Machine pattern classification, the laboratory testing for identifying acoustic signal of gas pipeline leakage is presented. Finally, the field application demonstrates that the detection system could identify small gas leakage effectively and avoids false-alarms which caused by running conditions with a good prospect.  相似文献   

17.
利用井口自动化装置进行石油钻井过程中溢流、井喷时的关井作业是目前井控作业的热点。为了有效减少工作人员操作时间,保证装置的可靠性。提出了1种自动抢接止回阀装置,并将装置的控制系统设计成全液压系统。基于AMEsim对设计的液压系统进行建模以及模拟仿真分析,得到了执行元件(3个液压马达和1个伸缩液压缸)的输出特性曲线,然后与理论计算、设计及选型的执行元件的参数进行对比。研究结果表明:设计的液压回路可以确保自动抢接止回阀装置的整个工作过程正常、稳定的进行。设计的自动抢接止回阀装置的性能基本满足使用要求,具有一定的实用价值。  相似文献   

18.
Objective: A new method is suggested for coordination of vehicle motion actuators; where driver feedback and capabilities become natural elements in the prioritization.

Methods: The method is using a weighted least squares control allocation formulation, where driver characteristics can be added as virtual force constraints. The approach is in particular suitable for heavy commercial vehicles that in general are over actuated. The method is applied, in a specific use case, by running a simulation of a truck applying automatic braking on a split friction surface. Here the required driver steering angle, to maintain the intended direction, is limited by a constant threshold. This constant is automatically accounted for when balancing actuator usage in the method.

Results: Simulation results show that the actual required driver steering angle can be expected to match the set constant well. Furthermore, the stopping distance is very much affected by this set capability of the driver to handle the lateral disturbance, as expected.

Conclusion: In general the capability of the driver to handle disturbances should be estimated in real-time, considering driver mental state. By using the method it will then be possible to estimate e.g. stopping distance implied from this. The setup has the potential of even shortening the stopping distance, when the driver is estimated as active, this compared to currently available systems. The approach is feasible for real-time applications and requires only measurable vehicle quantities for parameterization. Examples of other suitable applications in scope of the method would be electronic stability control, lateral stability control at launch and optimal cornering arbitration.  相似文献   

19.
光声光谱火灾气体探测系统   总被引:1,自引:1,他引:0  
气体是火灾中最早出现的燃烧产物,利用燃烧过程中产生的气体作为判据能在很大程度上提高火灾探测及预警的早期性。光声光谱技术由于其在气体检测领域的高灵敏度、宽检测范围等优点已成为火灾探测的一个重要的发展方向。介绍了光声光谱技术原理,设计了一套基于光声原理的火灾气体探测系统。对该系统的基本性能进行了测试,并对棉绳阴燃和聚氨酯泡沫明火实验中产生的气体浓度(CO)进行了测量,根据光声信号的变化并结合一定的算法反演得到了这两组实验中CO的浓度变化曲线。实验表明,该探测系统对火灾能够很好地响应,能够满足探测需求。  相似文献   

20.
根据前馈式、反馈式和连续式安全控制的特点建立了石化流程安全控制模型和信号流图,运用Mason公式求出了安全控制模型的解并对其进行了实例分析。认为实现石化流程安全运行的重点在于配备可靠的紧急停车系统,有效控制事故的初发隐患。  相似文献   

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