基于ARM与线性CCD的高速数据采集系统论文中英文资料对照外文翻译

1、基于ARM与线性CCD的高速数据采集系统毕业论文 中英文资料对照外文翻译文献综述 HighHigh Speed Data Acquisition System Based on ARM Linear CCD; Contact-line; Pantograph; Stagger value I. IntroductionI. Introduction In electrification railways, in order to extend the life of the pantograph on electric locomotives, so that the slider of pa

2、ntograph wear evenly, the contact-line (electrified railway power feed line) in straight-line segments is arranged as zigzag route (curve section arranged in the form of polyline). The distance between the contact-line of positioning point and the pantograph centerline track is called out stagger-va

3、lue, which is a key indicator of contact-line . Stagger-value can not be ignored, the value too small will affect the slider of pantograph wear evenly and the purpose of extending using life; otherwise, in some cases (such as caught in a stiff winds), cause a large range of lateral movement of the r

4、oof (and the higher the speed, the greater pantograph swing around), some parts of contact-line will be in excess of the effective work length of pantograph, so that the stagger-value of contact-line beyond the standard range, leading to deterioration of the current collection, and even cause incorr

5、ect running of the pantograph accident. Pantograph-catenary malfunction will result in interruption of train operation, which impact on rail transport seriously.In order to avoid these phenomena, the stagger-value and its changes should be tested regularly.Therefore, a locomotive contact-line monito

6、ring system and its mating data acquisition system were developed, which calculate the instant stagger-value quickly. II. System ComponentsII. System Components System hardware components are shown in figure 1. The system consists of the following components: (1) using TOSHIBA Companys high-speed li

7、near array CCD to achieve the digitization of contact-line images (CCD output the signal of corresponding time sequence of position); (2) using Atmel Companys AT91RM9200 processor of ARM9 series to realize digital signal acquisition and processing; (3) using PDIUSBD12 USB interface device to complet

8、e the data communications between measurement system and the PC. Due to the characteristics of its improved Harvard structure, specialinstructions and quick to realize a variety of signal processing, ARM processor is widely used in image processing, communications, radar, sonar, precision machinery

9、fields, etc. ARM processor is adopted for its arithmetic speed and bus width. As the real-time signal analysis and calculation require a high sp eed of computing, Atmel Companys ARMchip AT91RM9200isselected.ThechipisARM920Tbased, high-performance, low power consumption 16/32-bit RISC(reduced instruc

10、tion set computer) microcontroller, which incorporates a rich set of application peripherals and provide a single-chip solution for industrial control applications that require a wide range of peripherals at low power consumption and strictly stable working. Fig 1 System block diagram III. Real-time

11、 processing and transmission of CCD digital imageIII. Real-time processing and transmission of CCD digital image In order to achieve real-time digital image transmission, several major factors which affect real-time transmission should be necessary to solve: First, the speed of linear array CCD data

12、 acquisition; Second, the transmission speed between linear array CCD and ARM processor; the third is the data transmission speed between ARM processor and computer. The following will be described in detail. A. Linear array CCD acquisition speedA. Linear array CCD acquisition speed Acquisition spee

13、d is a critical performance indicator for image sensor, TOSHIBA Companys TCD1209D linear array CCD is used to meet the targets. Its clock pulse frequency can operate as high as 20MHz, especially suitable for high-speed conditions of size measurement and dynamic analysis. Fig 2 Linear CCD TCD1209D an

14、d its time sequence diagram Linear array CCD TCD1209D and its time sequence diagram are shown in figure 2. B.Transmission speed between CCD and ARM processor In order to improve the speed of CCD data acquisition and reduce conversion time, adopting high speed A/D converter can make it exchange data

15、with ARM processor at high-speed. ADC08200, Analog Companys nanosecond conversion device is adopted. Its a single-channel, 8-bit A/D converter, which operates over a wide range of temperature, converts fast, operates at conversion rates up to 230 MSPS, thus achieving entire signal acquisition of lin

16、ear array CCD. ADC08200 is shown in figure 3. Fig 3 High-speed A/D converter ADC080200 FIFO is used as a data buffer to co-ordinate the rate of ARM processor and ADC. It is a two-port (input and output port) memory for temporary storage of first in first out data. Due to the time to write data toFIF

17、O is far less than the A/D conversion time, therefore, the acquisition speed depends on the A/D conversion speed. In order to improve the speed of the entire measurement system, the time sequence of entire circuit is precisely controlled by the CPLD to make the circuit works harmonious. CCD driving

18、signal, integration time control, address decoding, A/D conversion control, data buffer and data acquisition logic functions integrate in the CPLD, so that the entire circuit structure is simple and reliable. In order to further enhance the system speed, when the system starts, system programs are t

19、ransferred to high-speed SRAM for running and SDRAM for data storage; SRAM, SDRAM should be placed as close as possible to ARM processors, and the signal lines the shortest possible. ARM processor (AT91RM9200), the signal processing core of the entire hardware system, read the CCD light intensity si

20、gnal from FIFO, calculate the distribution of contact-line image in the CCD with corresponding algorithm, and transfer the result to the slave computer through USB. C. Transmission speed between ARM processor and computerC. Transmission speed between ARM processor and computer In order to increase t

21、he speed of data transmission and reduce transmission delay, USB interface is used for data transmission. USB1.1 interface support low-speed and full-speed transmission, data transfer rates has reached 1.5Mbps in low-speed mode, the transmission speed up to 12Mbps in full speed mode. Philips Company

22、s PDIUSBD12 is adopted. When a USB device inserted into the PC, PC enumerates USB device automatically. When detecting equipment to insert, PC send query request. USB devices respond to the request and send equipment Vendor ID and Product ID; PC loads the corresponding device driver with these two I

23、D to complete the enumeration process. PC-side USB device driver is completed by WinDriver. Data communication between PC and USB equipment mainly includes two aspects: first, read the sample data; second, send control commands to the acquisition system. IVIV. CCD image recognition algorithm. CCD im

24、age recognition algorithm ARM processor is mainly responsible for the solution of stagger-value; its the process of image identification, including background separation and feature extraction of the image data. Identification of the image is for image gray only; the standard deviation threshold tra

25、cking method is adopted. The image is composed of black-and-white texture, and gray-scale varies greatly, with a larger standard deviation; and background gray distribution is relatively flat, with small standard deviation. Therefore, the standard deviation of each point as the center of a group of

26、pixels is calculated, the value greater than a certain threshold determine the point in the foreground, or as the background. This system not only measures the contact-line instant position, but also calculates the abrasion state of the contact-line to evaluate its life span. System support by assoc

27、iated PC software, through subsequent playback of the data collected, to check the situation of stagger-value, as well as the abrasion of contact-line, and decide whether to adjust and replace or not V V. Measures of improving system reliability. Measures of improving system reliability High-speed d

28、ata acquisition system is inevitably affected by interference from the external environment. As the complex environment around the measurement system, many factors interfere with the system. Electromagnetic interference around 27.5KV high-voltage catenary affects great; the pantograph detaching will

29、 be accompanied by the emergence of arc sparks, this phenomenon interfere with communication line along the lines, accompanied by high-frequency electromagnetic waves, therefore, necessary anti-interference measures should be taken.In order to improve the ability ofanti-interference,anti-jammingmeas

30、urestakenareasfollows:take anti-interference design of PCB circuit to reduce the external interference on system; all cables adopt shielded cable with wave-proof sleeve; equipment shell adopts shielding material and detection window of the shell use gauze to isolate the interference. VI. ResultsVI.

31、Results We have used this high speed data acquisition system in Wuhan south locomotive-depot to measure the contact-line instant position, and the test result shows that the whole system works effective, fast and high degree of accuracy; exclude the vibration of the train and the contact-line, it re

32、ach the accuracy of 0.1mm. This design is flexible and corresponds with the actual needs. REFERENCESREFERENCES 1Yu Wanju. Design and the Measurement Theory of Contact-line M, Beijing, China Railway Publishing House, 1991. 2Zhu Feixiong. Detection of Stitched catenary suspension J, Electric Railway,

33、2003,(1):15-17 3Li Weimin, Xing Xiaozheng. Application of DSP in the Linear CCD measuring system J, Chinese Journal of Scientific Instrument, 2003,(2):183-185 4Huang Zhengjin, Xu Jian. Introduction to CPLD system design and application technology M, Beijing, Publishing House of Electronics Industry,

34、 2002. 5Cao Xiaowei. The principle and application of high-speed high-precision linear array CCD-TCD141C J, International Electronic Elements, 1997,(8):26-29 6Bi Youming, Yang Tiemei. High-speed data acquisition and processing system for linear CCD J, Journal of Taiyuan University of Science and Tec

35、hnology, 2000, (1): 31-33 7Wang Ning, Shan Shengxiong. Analysis of the contact force between pantograph and catenary J, Electric Railway, 2000, (2): 22-24 8Bai Dongliang. A new structure of the pantographSelf-detaching pantograph J, Electric Drive for Locomotives, 1999, (6): 42-43 9He Duyang, Huang

36、Xiaodong, He Kui. The Width Measuring Instrument for Steel Plate by Linear CCD Technology. Technology and Test. 2007, 5:64-66. 10Wang Qingyou, Zhang Kexin, Jin Gui, Liu Haijun. Design of linear CCD real-time test system based on DSP. Electronic Measurement Technology, 2007, 30(7): 85-86. 11Zhong Hon

37、gtao, Duan Fajie, Wang Xueying, YE Shenghua. Design of CCD Driver on Auto-adjust Exposure Time. Chinese Journal of Sensors and Actuators.2006, 19(6):2256-2259. Dong JianJun, Master, Lector， The First Aeronautical Technical College of the Air Force. Xinyang 464000. China.Email: dbrother Zhao Xiaojin,

38、 Master, College of Mechanicaland Electrical Engineering, Xian UniversityofArchitecture&Technology,Xian710055.China.Email: zhaoxiaojin 基于基于 ARMARM 与线性与线性 CCDCCD 的高速数据采集系统的高速数据采集系统 摘要摘要 本文介绍了一个基于 ARM 的线性 CCD 高速采集系统，系统中选择了高速线性 CCD 和高速 ADC。因为 ADC 的采样速度相对 ARM 的工作时钟频率较慢，所以使用 CPLD 和 FIFO 作为 A/D 和 ARM 之间的

39、I/O 接口。它使电路工作在更加平稳、简洁 而易于控制，同时也提高了 ARM 的工作效率。为了提高通信速度，这里采用通用 串行总线（USB）技术来与 PC 进行通信。 ARM 是用来控制主处理器的数据采集， 数据的计算和数据传输。结果证明，整个系统能高效运作。该系统可应用于高速 数据采集及多路模拟信号的工作环境下。 关键词：ARM；线性 CCD；接触线；受电弓；错开值 1 1引言引言 在电气化铁路，为了扩大对电力机车受电弓的寿命，所以要使受电弓滑块磨 损均匀，接触线的直线段（电气化铁路供电线）排列为曲折路线（弯段被安排成 折线的形式） 。之间的接触线的定位点和受电弓轨道中心线距离称为错开值，这

40、 是一种接触线的关键指标。 错开值是不可忽视的，这个值过小会影响到受电弓滑块磨损的均匀性，从而 影响到延长使用寿命的目的，然而，在某些情况下（比如陷入了激烈的风中） ， 造成大范围的在屋部的横向运动（并且速度越快，受电弓的左右摆动越剧烈） ， 接触线将在某些部分将会超过受电弓的有效工作长度，从而使错开，接触线值超 出标准范围的错开值，导致了当前连接的破坏， 甚至导致了会产生受电弓事故的 错误运行。受电弓与滑触线发生故障，将导致列车正常运行的中断，从而对铁路 运输产生严重的影响。 为了避免这些情况， 错开值及其变化应经常性地予以测试。 因此， 一个机车的接触线式在线监测系统，及与其配套的数据采集

41、系统被开发出 来，它的工作是实时地、迅速地计算错开值。 2 2系统组件系统组件 系统硬件组成如图 1 所示。 该系统由下列部分组成： （1）采用东芝公司的高速线阵CCD 实现接触线影像 的数字化（CCD 输出对应的时间序列位置的信号） ， （2）采用 Atmel 公司 ARM9 系 列处理器中的 AT91RM9200，实现了数字信号的采集和处理； （3）采用 PDIUSBD12 的 USB 接口设备，完成测量系统与 PC 机之间的数据通讯。 由于它改进型的哈佛结构，特殊的指令系统以及迅速实现各种信号处理的特 点，ARM 处理器被广泛应用于图像处理，通信，雷达，声纳，精密机械等领域。 ARM 处

42、理器正因其算术速度和总线宽度而被采用。随着实时信号分析和计算都需 要很快运算速度，所以系统选择了 ATMEL 公司的 ARM 芯片 AT91RM9200。该芯片 是基于 ARM920T 的，高性能，低功耗的 16/32 位 RISC（精简指令集计算机）微 控制器，它集成了一套丰富的外围设备的应用，并在那些需要一大批外围设备， 并能在低功耗的外设和严格稳定工作的工业控制应用中， 提供了一个单芯片的解 决方案。 图 1系统硬件组成 3 CCD3 CCD 数字图像的实时处理与传输数字图像的实时处理与传输 为了实现实时的数字图像的传输，几大影响实时传输的因素应该予以解决： 第一，线阵 CCD 的数据采

43、集速度；二是线阵 CCD 和 ARM 处理器之间的传输速度； 第三是 ARM 处理器和计算机之间的数据传输速度。下面将给以详细描述。 A.线阵 CCD 的采集速度 采集速度对于图像传感器来说，是一个关键的性能指标，这里采用东芝公司 的 TCD1209D 线阵 CCD 来满足目标要求。它可工作在可高达 20MHz 的时钟脉冲频 率下，所以对高速条件下的尺寸测量和动态分析特别适合。 图 2 TCD1209D 及它的时序 线阵 CCD TCD1209D，以及它的时序图如图 2 所示。 B.CCD 和 ARM 处理器之间的传输速度 为了提高 CCD 的数据采集速度，减少转换时间，现使用高速A/D 转换器，以 使它在高速环境下与 ARM 处理器进行数据交换。这里选择 ADC08200，Analog 公 司的一个纳秒级转换器。这是一个单通道，8 位的 A/D 转换器，它可以在一较宽 的温度范围内工作，转换速度快，工作时的转换速率高达 230 MSPS，从而实现 整个线阵 CCD 的信号采集。ADC08200 如图 3 所示。 图 3 ADC08200 FIFO 用于作为数据缓冲区， 协调了 ARM 处理器和 ADC 的速率。这是一个两端 口（输入和输出端口）的，临