基于FPGA和USB2．0的数据采集系统

文中介绍了基于FPGA和USB2.0数据采集系统的设计与实现方法.设计采用FPGA作为整个系统的控制芯片,实现对USB芯片的控制,数据传输过程的控制,Flash存储器控制以及外围电路的控制.介绍了该系统的结构,详述了关键硬件电路模块,分析了软件工作流程.实验证明:该系统能完成实时数据采集和处理,是一种通用性较强的数据采集系统.     

基于LabView的机械密封试验数据采集与控制

基于LabView软件开发了机械密封试验数据采集系统,分析了采集系统的基本要求及其基本框架结构,实现了系统的自动控制、数据采集、数据实时显示、数据存储以及历史数据查询等功能.介绍了试验系统软件的实现方法,并给出了系统自动控制、参数设置、数据采集、数据定时保存、数据分析和实时波形显示等关键环节的设计要点和具体程序框图.最后对所设计的数据采集系统进行了性能测试,结果表明所设计的系统可以满足机械密封试验的要求.     

遥测数据采集系统的设计探讨

介绍了以自动雨量等参数测量为主的数据采集系统的设计.系统采用大规模单片机为核心,外围以事件触发唤醒电路以及低功耗方式的实现,通过电台、短信模块和卫星等无线传输方式,将数据从测站传回中心站.     

基于VB的压力传感器数据采集系统上位机软件的设计

介绍了一种基于VB6.0软件编写的实时压力数据采集系统的上位机软件,上位机通过USB接口与数据采集卡进行通信,实现了数据的实时显示、曲线绘制.并且能够对数据和曲线进行保存.文中介绍了几个主要模块功能的设计以及实现方法.     

基于CC2420和ADXL330的无线传感器数据采集系统

研究基于无线传感器网络(WSN)的数据采集系统.简要介绍了ZigBee技术协议以及CC2420和ADXL330的性能和特点,设计了一种基于CC2420和ADXL330的无线传感器数据采集系统,给出了具体的软、硬件设计方法.该系统选用高灵敏度的三轴加速度传感器芯片ADXL330来采集管道破坏时产生的振动加速度信号,通过支持ZigBee无线传输协议的CC2420把数据发送给接收装置.     

基于LabView的阀门试验数据采集系统

介绍了利用LabView设计的数据采集系统,重点说明了系统的软硬件组成和虑除干扰的模拟和数字滤波器的设计,为类似的数据采集系统的设计提供参考.     

一种基于USB的数据采集系统设计

介绍了一种基于USB接口的数据采集系统的设计,通过合理的电路设计以及基于硬件的高效软件,使得系统在实际应用中取得了较好的运行效果.     

基于ARM的汽车侧向行驶参数采集系统

为给车辆稳定性控制系统提供基本运动参数,设计了一种采用ARM7LPC2200为核心控制器、以MEMS惯性测量模块ADIS16355为车辆六自由度运动参数检测传感器的数据采集系统.文中首先简要介绍了汽车行驶参数数据采集系统的系统组成及LPC2200、ADIS16355传感器的工作原理,结构特点,详细介绍了汽车侧向运动参数采集系统的SPI接口设计,并对行驶过程中的侧向加速度以及横摆角速度行进实车测量.实验数据表明,采集系统工作稳定,数据可靠,达到了汽车运动参数测量的要求.     

基于GPRS的轨道状态远程监测系统

设计了基于GPRS的轨道状态远程监测系统,详细介绍了系统的组成,通过GPRS模块建立GPRS连接的过程以及通过PPP协议实现数据传送和监控的过程,该系统对于轨道状态远程监控的实现具有实际应用价值.     

汽车AMT数据采集与分析系统研究

数据采集与分析系统对AMT系统的开发有重要意义.本文介绍了基于串行通信与虚拟仪器技术的汽车AMT数据采集与分析系统,阐述了系统的工作原理以及软、硬件的设计.     

三绕组变压器的双绕组等效建模及在Matpower中的应用

针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。     

On the Relation of Load to Average Gap in the Contact Between Surfaces with Longitudinal Roughness

A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load.     

电站锅炉模糊风险评价方法研究与应用

针对电站锅炉风险等级评价问题,将模糊综合评价技术应用到电站锅炉风险等级评价中。开展了电站锅炉失效影响因素及模糊评价因素的重要程度分析,建立了一套科学合理适于在线评价的电站锅炉风险评价体系,提出了模糊综合评价技术与改进的模糊层次分析法相结合的模糊风险评价方法,利用改进的模糊层次分析法计算了指标体系中各层指标权重。对某一台电站锅炉的实际运行工况影响子因素进行了模糊风险评价,采用模糊合成算子进行模糊综合运算得到电了站锅炉运行工况影响子因素的评价向量。研究结果表明:电站锅炉的运行工况影响子因素的风险评价等级为第6级,失效可能性等级为小,该电站锅炉运行工况良好。     

交通荷载作用下桥梁结构参数识别方法

应用动力节点加载法,将作用在桥梁上的交通荷载转化为等效节点荷载,再用两步构造法识别结构物理参数.第1步,用Newmark-β方法变换结构运动方程,并用结构的加速度响应求得变换空间内的位移、速度和加速度响应;第2步,基于最小二乘原理,构造出变换空间内求解结构参数的递推式,进行结构物理参数识别.数值模拟结果表明,在交通荷载作用下,该方法能够快速、准确地进行桥梁结构参数识别.     

RLS and LMS blind adaptive multi-user detection method and comparison in acoustic communication

RLS and LMS blind adaptive multi-user detection algorithm and multi-user detector was proposed to solve the problem of multi-user signal detection problem encountered in underwater acoustic communication networks.In simulation analysis,RLS and the LMS blind adaptive multi-user detector were designed and tested for synchronous and asynchronous multi-user communication process.The results of SIR comparison and MMSE comparison show that,both of the two methods can realize blind adaptive detection when any user change in multi-user communication,during this process,the training communication sequences are not needed.The RLS algorithm has about 5 dB higher in SIR compared with LMS algorithm,and the convergence velocity of RLS algorithm is also higher than LMS algorithm when the communication users change.RLS algorithm has better ability in multi-user detection than that of LMS algorithm,and it has great attraction and guiding significance for solving the problem of multiple access interference(MAI) in multi-user communication.     

Robust Impedance Control of Robots Using an Adaptive Interaction Force Observer

For robot interaction control,the interaction force between the robot and the manipulated object or environment should be monitored.Impedance control is a type ...     

Research on key techniques of expendable conductivity temperature depth measuring system

This paper analysis the developing of expendable conductivity temperature depth measuring system(XCTD)and introduce its principle of measuring about temperature,salinity and depth of ocean.Some key techniques are put forward.According to the real needs of XCTD,conductivity sensor with high sensitivity is designed by principle of electromagnetic induce,the ocean conductivity from induced electromotive force has been calculated.Adding temperature correction circuit would help to reduce error of conductivity measurement because of sharply changing temperature.Advanced temperature measuring circuit of high precision and the constant current source is used to weaken effect of self-heating of resistance and fluctuation of the source.On respect of remote data transmission,LVDS is a good choice for the purpose of guarantee the quality of data transmitted and the transmission distance is reaching to thousand meters in the seawater.Modular programming method is also brought into this research aimed at improve the stability,reliability and maintainability of the whole measuring system.In February,2015,the trials in South China Sea demonstrate that the developed XCTD realize effective measurement at a speed of 6 knots and detection depth at 800 m.The consistency coefficient of the acquired data is greater than 0.99 and the success rate of probe launching is above 90%.     

CHARACTERISTCS OF FLUID FILM IN OPTIMIZED SPIRAL GROOVE MECHANICAL SEAL

In order to investigate the sealing performance variation resulted from the thermal deformation of the end faces, the equations to calculate the fluid film pressure distribution, the bearing force and the leakage rate are derived, for the fluid film both in parallel gap and in wedgy gap. The geometrical parameters of the sealing members are optimized by means of heat transfer analysis and complex method. The analysis results indicate that the shallow spiral grooves can generate hydrodynamic pressure while the rotating ring rotates and the bearing force of the fluid film in spiral groove end faces is much larger than that in the flat end faces. The deformation increases the bearing force of the fluid film in flat end faces, but it decreases the hydrodynamic pressure of the fluid film in spiral groove end faces. The gap dimensions which determine the characteristics of the fluid film is obtained by coupling analysis of the frictional heat and the thermal deformation in consideration of the equilibrium condition of the bearing force and the closing force. For different gap dimensions, the relationship between the closing force and the leakage rate is also investigated, based on which the leakage rate can be controlled by adjusting the closing force.     

Quantum Cooperative Robotics and Autonomy

The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...     

OPTIMIZATION METHOD ON IMPELLER MERIDIONAL CONTOUR AND 3D BLADE

An optimization method for 3D blade and meridional contour of centrifugal or mixed-flow impeller based on the 3D viscous computational fluid dynamics (CFD) analysis is proposed. The blade is indirectly parameterized using the angular momentum and calculated by inverse design method. The design variables are separated into two categories: the meridional contour design variables and the blade design variables. Firstly, only the blade is optimized using genetic algorithm with the meridional contour remained constant. The artificial neural network (ANN) techniques with the training sample data schemed according to design of experiment theory are adopted to construct the response relation between the blade design variables and the impeller performance. Then, based on the ANN approximated relation between the meridional contour design variables and impeller performance, the meridional contour is optimized. Fewer design variables and less calculation effort is required in this method that may be widely used in the optimization of three-dimension impellers. An optimized impeller in a mixed-flow pump, where the head and the efficiency are enhanced by 12.9% and 4.5% respectively, confirms the validity of this newly proposed method.