Dissertation > Excellent graduate degree dissertation topics show

The Design of Strain Detection System with High Accuracy Based on Total Differential Theory

Author: LiuFang
Tutor: ZhangJiaZuo
School: Northeast Forestry University
Course: Detection Technology and Automation
Keywords: Strain measurement The theory of total differential Double-channel High-accuracy
CLC: TP274
Type: Master's thesis
Year: 2011
Downloads: 53
Quote: 0
Read: Download Dissertation

Abstract


The detection of strain and stress is widely used in the field of construction, material, machinofacture and so on. In the process of measurement, sensitive components convert the measurands such as displacement, acceleration into strain or stress, the measurement of the measuring parameter is realized by using strain detection circuit of displacement and acceleration. In the actual industrial environment, most strain signal are small-single, and in the measuring process, the components are impressed by fluctuation of power-supply, the ageing of electrical components, drifting, noise jamming and so on, which make it harder to achieve the detection signal with high-accuracy.Aiming to detecting the strain with high-accuracy, the study on the basis of the differential theory, double-channel parameters measurement of the detection circuit design method is put forward, and the whole bridge type strain gauge dual channel detection circuit, the whole bridge and resistance strain gauge with dual channel detection circuit and the strain gauge half bridge type double-channel detection circuit are designed. To eliminate influences caused by the interference factors, using the total differential theory, three detection circuits are analysed, through the configuration of components in test circuit, the applicability of the detection circuit is improved, in theory, the linearization of detection circuit transfer function is realized, and the influence of the circuit components caused by outside interference factors is eliminated when the detecting circuit be at work.To eliminate the influence caused by the drifting of detecting system on the measurand, two step measurement is used in the design of the hardware circuit of this system:first step, make no input single to the system, the value named instantaneous zero drift is detected at the output; second step, measure the measuring strain signal. Dispose the two kinds of single and convert them into digital signals and let them be the input of MCU78E58, dispose the measuring single in the MCU by the converting arithmetic to eliminate the zero drift, after the calculate of the computer, the measuring strain values are received. Finally, the value of strain transfer to the PC through the interface of communication.The software corresponding the detection system is designed in the PC. Serial communi-cation is realized by MSComm. The software is compiled by C++ which is object-oriented programming language, and the data base is the SQL Server 2000 which is used for storing the values transformed by MCU, the technique named ADO is used to call the values in the data base. The software include three functions as follow:display the value instantly and dynami-cally, display the recorded data as the form of data and chart, this is convenient to analyze the strain values. This software has good portability, this make the practical applicability of the strain detection system strengthened. Meanwhile the software design process based to modul- arization, so it can increase the function of the software and upgrades according to actual application.For proving the practical applicability of system, two experiments are conducted. The one uses the standard resistances valued 120Ωand resistance box with high accuracy as the analog strain gage to detected the strain, the other one is testing the strain of the steel of NO. 235 when the steel is stretch to measuring the strain. The experiment shows that the resolution ratio of the system is 1με, the accuracy is 0.5%FS, which indicate the system has good linearity and high accuracy, and the system has excellent stability and anti-interference.

Related Dissertations

  1. Determination on Heavy Metals and Distributing of Baiyang Lake,X832
  2. The SFDM/WDM Method of Fiber-Optic Fabry-Perot Sensors,TP212.14
  3. Monocycle Encoder and Its Real-time Error Correction Techniques,TN762
  4. Research and Application of the Method of Smoothing Transfer of Inter-trajectory for High-speed and High-accuracy Machining,TG659
  5. Experimental Determination of the Mechanical Properties of Invisible Appliance with Different Thickness,R783.5
  6. Three-phase high accuracy energy metering circuit design,TM933.4
  7. Research on Practical Techniques of White-light Interferometer Signal Demodulation and Processing,TN911.3
  8. Study About Shear Lag Characteristic in the Self-Balancing Construction of Large Span Prestressed Concrete Box Girder Bridges,U448.213
  9. Research on the Fiber Grating Based High-accuracy Temperature/Strain Sensing System,TP212.14
  10. Dynamic Strain Measurement Instrument Based on Virtual Instrument Technology,TH823.3
  11. The Geophysical Application Research on Deep Concealed Ore Deposit Prediction in LALA Copper Mines and Its Peripheral Area,P631
  12. Pipeline transportation of natural gas hydrates and double channel lift pump flow analysis,TE973
  13. Strength Analysis and Structure Improvement of the Key Component of Ladle Turret,TF341.6
  14. Remote Corrosion Monitoring System of Concrete Structures,TU375
  15. Test Research of High Performance Power Management IC,TN492
  16. The Research and Application of High Accuracy 3D Seismic Exploration in Biyang Depression,P631.4
  17. Strain Gauge integrated design and calibration technology,TP212.12
  18. Precise Location by Radio Phase Detecting Technology,TQ520.5
  19. Optimization Research and Fracture Properties of SiC/Al Functionally Gradient Material under Elevated-Temperature,TB34
  20. Dual shimmer color night vision technology research,TN22
  21. Prediction of Stresses on Orifices and Evaluation of Constraints on Crack-tips,O346.1

CLC: > Industrial Technology > Automation technology,computer technology > Automation technology and equipment > Automation systems > Data processing, data processing system
© 2012 www.DissertationTopic.Net  Mobile