xPC目标在EPS试验台电机控制中的应用

针对汽车电动助力转向试验平台,利用Matlab/Simulink和xPC 目标工具箱实现了对伺服电机的控制.通过组建低成本的双机型快速实时仿真系统,开发xPC目标工具箱下PCI-1720数据卡的驱动程序,连接试验电路,并对电动助力转向试验平台中的伺服电机进行加载实验,结果表明xPC控制的伺服电机能够随着转角变化而加载相应变化的转矩,达到了通过双机型实时控制伺服电机加载的目的.通过开发xPC的驱动程序扩展了xPC工具箱的应用范围,增强了Matlab与硬件通信的能力.     

电动车增程器控制单元的硬件在环仿真系统设计

基于增程器的工作原理,并结合增程器控制单元的开发要求,采用了MATLAB/xPC Target的实时仿真环境构架,分别从硬件在环仿真(HILS)系统的硬件和软件两个方面对增程器控制单元的硬件在环仿真系统进行设计与开发。整个平台包括基础平台、信号接口系统、模拟负载系统和监控软件等部分。开发的HILS系统应用于增程器控制单元的设计开发和功能测试,缩短了增程器控制单元的开发周期。     

基于模糊PID的客车防抱死制动系统硬件在环测试试验研究

基于硬件在环测试方法,搭建了客车防抱死制动系统制动硬件在环测试系统。该系统包括Matlab/xPC目标实时环境、气制动系统和整车动力学模型3部分,可对客车制动输出力进行实时数据采集计算。针对整车制动ABS控制策略引入了参数自整定模糊PID控制算法,并测试了客车在高、低附着系数路面的制动情况。测试结果表明:本方法能够很好地根据制动情况对PID参数进行实时整定,始终将车轮滑移率稳定在最佳滑移率0.2(高附着系数)和0.1(低附着系数)附近,具有良好的自适应性和控制精度。     

基于MATLAB的目标跟踪实时仿真库的设计与实现

利用 MATLAB/SIMUNKK 的代码产生原理,针对以 c6201 DSP 为核心的图像处理平台,开发目标跟踪实时仿真库,建立了目标跟踪实时仿真系统。在此环境下可将算法模型快速生成 DSP可执行程序,并可直接运行。此环境为算法研究者建立了算法到 DSP 程序开发的桥梁,使算法快速得到实时验证,大大节省 DSP 程序移植的时间。     

实时分布仿真环境下视景仿真系统的构建

随着仿真技术、计算机技术和网络技术的飞速发展,复杂系统仿真的应用领域不断扩大,对仿真过程的直观性、交互性和逼真度的需求日益提高.实时分布仿真环境下的视景仿真技术是仿真技术研究中的一项关键技术,因此对其进行研究具有重要的意义.对实时分布仿真环境下的视景仿真技术进行研究.分析实时分布仿真环境下视景仿真技术的需求,设计在实时分布仿真环境下视景仿真系统的构建,确定可行的软、硬件开发环境.     

一种高速目标检测算法研究及实现

为了实时有效的实现雷达跟踪高速运动目标检测,研究了小波检测器的算法和硬件实现。小波检测器的快速算法并对其作了优化设计构成检测系统的软件基础,采用ADSP21160DSP芯片开发出恒虚警检测并行处理系统。仿真结果和检测性能分析表明,该系统能有效检测低信噪比下高速运动目标,并且有很好的实时性。     

采用TMS320C6203的实时图像处理系统设计

针对高帧频、大视场图像中的实时目标检测、识别和跟踪,设计了一种以TMS320C6203为核心运算处理器,FPGA为辅助控制处理器的实时图像处理系统。在对弱小目标检测识别算法的实验分析基础上,开发了实时图像处理软件,使得该系统对弱小多目标的检测、识别和跟踪的能力达到了实际工程的实时性需求。     

一种变电站综合预警自动化系统设计

本文研究并开发的变电站综合预警自动化系统就是针对当前情况而开发的一整套使变电站安全运行的综合系统。预警系统可以监视变电站的安全运行及环境状况,实时监测变电站的运行环境,对变电站各种设备的运行状态及影响变电站安全运行的因素实现在线监测。     

嵌入式实时软件的构件化开发技术研究

嵌入式软件是一种较为特殊的软件,在嵌入式系统中所占的比重比较大,随着嵌入式系统的普及,嵌入式实时软件的构件化开发技术越来越受到重视。本文主要对构件化软件开发技术的主要内容和基本特点进行了分析,并对嵌入式实时软件的框架以及开发环境进行了探讨和研究。     

声纳基阵信号模拟器实时软件的开发

声纳基阵信号模拟器是一种实用的、可近似仿真实际监测目标及使用环境的阵元级信号发生器。声纳基阵信号模拟器的使用将有效缩短数字式声纳的研制周期，大大减少湖试和海试的次数。文章中以通用信号阵列处理系统为运行环境，详细介绍了一种声纳基阵信号模拟器实时多任务系统的软件设计与开发过程，分析了该软件系统中所有基本任务的功能以及多任务之间的通信关系，并且最后给出了该实时多任务软件在通用信号处理机上的实现拓扑图。实践证明，该套软件功能完备，且具有很好的实时性和稳定性，非常适用于现代声纳工程领域。     

Minimization of number of metrological parameters for dataacquisition systems

This paper considers the metrological model of the data acquisition system (DAS). The main attention is focused on the DAS on the basis of the sigma-delta analog-to-digital converter. The choice of the minimum number of parameters of the DAS allowing evaluation of the uncertainty of A/D conversion with reasonable accuracy is investigated     

A data acquisition system for machine tool condition monitoring

A flexible, generically applicable and inexpensive data acquisition system (DAS), for machine tool condition monitoring, has been designed, constructed and installed as part of a European Union sponsored project. The DAS is more than just a data logger and an array of sensors. It also consists of a methodology for analysing data logging requirements and a relational database that supports this methodology. The database is held on a central ‘maintenance management’ computer. The monitoring to be carried out by the DAS is specified through this database, which contains detailed information about the DAS's facilities. This feature makes it simple to reconfigure the DAS to implement new monitoring requirements and to customize its operation to meet the needs of different machines. The information in the database is transformed into a look-up table that is read by the software that sets up and controls the data logging processes.     

Quantitative estimation of measurement errors for general technological parameters

Results are presented on the metrological characteristics of multichannel data-acquisition systems (DAS) that perform indirect measurements. General and typical structures are given for such DAS, which are represented by mathematical models for the errors in processing the data in them. An analysis is presented of the dependence of the error on the DAS parameters and input signals.Translated from Izmeritelnaya Tekhnika, No. 10, pp. 16–20, October, 2004.     

数据采集系统动态特性的总体评价

数据采集系统动态特性的辨识和评价，是其总体性能评价中至关重要的一个目标。本文通过选取几个相互比较独立的指标来总体描述数据采集系统的动态特性，然后通过几个特殊的模型化方法将其动态特性分别以动态有效位数、传递函数、阶跃响应曲线和幅频特性、相频特性的方式给出，从而解决了数据采集系统动态特性的总体评价问题。     

配网自动化系统终端设备环境的安全运行管理

简述了杭州电力局配网自动化系统目前的概况,并依据当地的情况分析了自动化终端设备环境运行管理的注意事项,对运行管理中出现的自然气候、动物因素、电源保障和人为因素等四个方面的设备环境问题展开分析,同时提出相应的解决方案。     

通用串口通讯驱动程序设计

工业现场数据采集软件通常要面对来自不同厂家使用不同协议的现场仪表和控制器 .为了使数采软件能够适应各种不同的协议 ,同时要保持其他模块的稳定性 ,文章提出了一种通用串行通讯驱动程序设计方法 .数采软件只需通过该通用驱动程序打交道而不需要了解任何有关仪表使用的具体协议 .文章分析了目前常用的两种不同的协议模式 ;介绍了 MODBUS通讯协议 ,该协议是通用驱动程序的实现基础 ;分析了通用串口通讯驱动程序的结构 ,最后给出了实现该通用串口通讯驱动程序 C++类     

用周期倍差法评价数据采集系统的传递函数

数据采集系统传递函数的辨识和评价,是其总体性能评价中至关重要的一个目标,在此,首要的前提条件是其瞬态响应的获得。由于采样周期是有下限的,即采集速率不可能无限高,这在实际应用中常常限制了其瞬态响应特性的获得,因而也限制了其传递函数的辨识和评价。本介绍一种方法,通过对其加载特定的周期性输入信号,使用采样周期的整数倍和信号周期整数倍间的微小偏差,获得经实际采集得多的等效采样周期,从而解决了数据采集系统     

Application of X-Y separable 2-D array beamforming for increased frame rate and energy efficiency in handheld devices

Two-dimensional arrays present significant beamforming computational challenges because of their high channel count and data rate. These challenges are even more stringent when incorporating a 2-D transducer array into a battery-powered hand-held device, placing significant demands on power efficiency. Previous work in sonar and ultrasound indicates that 2-D array beamforming can be decomposed into two separable line-array beamforming operations. This has been used in conjunction with frequency-domain phase-based focusing to achieve fast volume imaging. In this paper, we analyze the imaging and computational performance of approximate near-field separable beamforming for high-quality delay-and-sum (DAS) beamforming and for a low-cost, phase-rotation-only beamforming method known as direct-sampled in-phase quadrature (DSIQ) beamforming. We show that when high-quality time-delay interpolation is used, separable DAS focusing introduces no noticeable imaging degradation under practical conditions. Similar results for DSIQ focusing are observed. In addition, a slight modification to the DSIQ focusing method greatly increases imaging contrast, making it comparable to that of DAS, despite having a wider main lobe and higher side lobes resulting from the limitations of phase-only time-delay interpolation. Compared with non-separable 2-D imaging, up to a 20-fold increase in frame rate is possible with the separable method. When implemented on a smart-phone-oriented processor to focus data from a 60 x 60 channel array using a 40 x 40 aperture, the frame rate per C-mode volume slice increases from 16 to 255 Hz for DAS, and from 11 to 193 Hz for DSIQ. Energy usage per frame is similarly reduced from 75 to 4.8 mJ/ frame for DAS, and from 107 to 6.3 mJ/frame for DSIQ. We also show that the separable method outperforms 2-D FFT-based focusing by a factor of 1.64 at these data sizes. This data indicates that with the optimal design choices, separable 2-D beamforming can significantly improve frame rate and battery life for hand-held devices with 2-D arrays.     

Effect of the cooling rate on the dendrite arm spacing and the ultimate tensile strength of cast iron

This paper describes a series of microstructural and strength studies performed on hypereutectic cast iron which was sand cast using a variety of end chills (metallic, non-metallic, water cooled and liquid nitrogen cooled, respectively). The effects of cooling rate on the dendrite arm spacing (DAS) and the ultimate tensile strength (UTS) were evaluated. Attempts were also made in the paper to explain these effects and to correlate the UTS with the DAS.     

A comparison of the Driving Anger Scale and the Propensity for Angry Driving Scale

The present study investigated the factor structures of the 14-item version of the DAS (Driving Anger Scale) and the Propensity for Angry Driving Scale (PADS) using a sample of New Zealand drivers drawn from the general population. The two scales were also investigated with regards to their relationships with general trait anger, risky driving behaviour, along with crash involvement and a variety of crash-related conditions. Confirmatory Factor Analysis supported both scales as unidimensional, although the PADS was reduced from a 19-item to an 18-item scale. Both the PADS and DAS were significantly related to trait anger, risky driving behaviour and near-misses. However, once the influence of the demographic variables and trait anger had been partialled out, the addition of the PADS and DAS made a significant contribution to predicting violations, but it was only the PADS which was significant. In contrast, after the demographic variables and trait anger had been partialled out, the addition of the DAS and PADS again made a significant contribution to the prediction of near-misses, but this time it was only the DAS which made a significant contribution. The present study clearly shows that both scales are robust measures, measuring similar, but slightly different aspects of driving anger.