針對(duì)材料試驗(yàn)機(jī)等設(shè)備中要求測(cè)量或控制材料拉伸或壓縮的位移，一般采用光電軸角編碼器檢測(cè)位置信號(hào)，輸出正交編碼脈沖信號(hào)。若采用其他方法檢測(cè)位置信號(hào)，必然導(dǎo)致電路設(shè)計(jì)復(fù)雜，可靠性降低。因此，提出一種基于LS7266R1的電子式萬(wàn)能材料試驗(yàn)機(jī)設(shè)計(jì)方案。給出了試驗(yàn)機(jī)中的控制器工作原理，LS7266R1與單片機(jī)的接口硬件設(shè)計(jì)，以及主程序軟件流程圖。巧妙地把力量傳感器，位移傳感器等機(jī)械運(yùn)動(dòng)狀態(tài)的壓力或拉力以及位置坐標(biāo)，變成了電壓信號(hào)和電脈沖數(shù)字信號(hào)，供A/D測(cè)量和LS7266R1計(jì)數(shù)，從而實(shí)現(xiàn)了獨(dú)立完成材料試驗(yàn)控制或通過(guò)PC機(jī)串口命令完成材料試驗(yàn)控制。
Abstract:
Aiming at the requirement that the displacement of the tension and compression always be tested and controlled in the equipement such as material testing machine. The position signal was tested by photoelectric axial angle coder. Therefore， the paper proposes the design of electronic universal testing machine design based on LS7266R1. If the position signal detected by other methods， will inevitably lead to the circuit design complexity， reliability decreased. The work theory of the controller， the hardware interface design between LS7266R1 and single chip， and the flow chart of main program， are presented in this paper. The signal of the compression or tension power and displacement at working， which tested by power sensor and displacement sensor especially， is changed into electric voltage and electric pulse numerical signals. And these signals can be tested by A/D and counted by LS7266R1. Finally the test of the material properties can be controlled by itself， or controlled by the COM command of PC.
基于PIC單片機(jī)的脈沖電源:設(shè)計(jì)了一種金屬凝固過(guò)程用脈沖電源。該電源采用PIC16F877作為主控芯片，實(shí)現(xiàn)對(duì)窄脈沖電流幅值的檢測(cè)，以及時(shí)電流脈沖幅值根據(jù)模糊PID算法進(jìn)行閑環(huán)控制。使用結(jié)果表明：該電源的輸出脈沖波形良好，電流幅值穩(wěn)定，滿(mǎn)足合金材料凝固過(guò)程的工藝要求且運(yùn)行穩(wěn)定可靠。關(guān)鍵詞：脈沖電源；PIC16F877單片機(jī)；模糊PID；閑環(huán)控制
Abstract：A kind of pulse power supply was designed which uses in the metal solidification process ．．I11is power supply used PIC16F877 to take the master control chip reali on to the narrow pulse electric current peak-to-peak value examination，carried on the closed-loop control to the electric current pulse peak-to-peak value basis fuzzy PID algorithm．The use result indicated ，this power supply output se profile is good，and the electric current peak-to-p~k value is stable，It satisfies the alloy material solidification process the technological requirement and movement stable reliable，Key words：p se po wer supply；PIC16F877single-chip microcontroller；f r PID；closed-loop control
MCSÉ-51 Programmer's Guide and Instruction Set
The information presented in this chapter is collected from the MCSÉ-51 Architectural Overview and the HardwareDescription of the 8051, 8052 and 80C51 chapters of this book. The material has been selected and rearranged toform a quick and convenient reference for the programmers of the MCS-51. This guide pertains specifically to the8051, 8052 and 80C51.
6小時(shí)學(xué)會(huì)labview,
labview Six Hour Course – Instructor Notes
This zip file contains material designed to give students a working knowledge of labview in a 6 hour timeframe. The contents are:
Instructor Notes.doc – this document.
labviewIntroduction-SixHour.ppt – a PowerPoint presentation containing screenshots and notes on the topics covered by the course.
Convert C to F (Ex1).vi – Exercise 1 solution VI.
Convert C to F (Ex2).vi – Exercise 2 solution subVI.
Thermometer-DAQ (Ex2).vi – Exercise 2 solution VI.
Temperature Monitor (Ex3).vi – Exercise 3 solution VI.
Thermometer (Ex4).vi – Exercise 4 solution subVI.
Convert C to F (Ex4).vi – Exercise 4 solution subVI.
Temperature Logger (Ex4).vi – Exercise 4 solution VI.
Multiplot Graph (Ex5).vi – Exercise 5 solution VI.
Square Root (Ex6).vi – Exercise 6 solution VI.
State Machine 1 (Ex7).vi – Exercise 7 solution VI.
The slides can be presented in two three hour labs, or six one hour lectures. Depending on the time and resources available in class, you can choose whether to assign the exercises as homework or to be done in class. If you decide to assign the exercises in class, it is best to assign them in order with the presentation. This way the students can create VI’s while the relevant information is still fresh. The notes associated with the exercise slide should be sufficient to guide the students to a solution. The solution files included are one possible solution, but by no means the only solution.
This book contains information obtained from authentic and highly regarded sources. Reprinted material is quoted with permission, and sources are indicated. A wide variety of references are listed. Reasonable efforts have been made to publish reliable data and information, but the author and the publisher cannot assume responsibility for the validity of all materials or for the consequences of their use.
This book evolved over the past ten years from a set of lecture notes developed while teaching
the undergraduate Algorithms course at Berkeley and U.C. San Diego. Our way of teaching
this course evolved tremendously over these years in a number of directions, partly to address
our students' background (undeveloped formal skills outside of programming), and partly to
reect the maturing of the eld in general, as we have come to see it. The notes increasingly
crystallized into a narrative, and we progressively structured the course to emphasize the
?story line? implicit in the progression of the material. As a result, the topics were carefully
selected and clustered. No attempt was made to be encyclopedic, and this freed us to include
topics traditionally de-emphasized or omitted from most Algorithms books.
Calculation of the Differential Impedance of Tracks on FR4 substrates
There is a discrepancy between calculated and measured values of impedance for differential transmission lineson FR4. This is especially noticeable in the case of surface microstrip configurations. The anomaly is shown tobe due to the nature of the substrate material. This needs to be considered as a layered structure of epoxy resinand glass fibre. Calculations, using Boundary Element field methods, show that the distribution of the electricfield within this layered structure determines the apparent dielectric constant and therefore affects theimpedance. Thus FR4 cannot be considered to be uniform dielectric when calculating differential impedance.
