The Dial Indicator Verification System Based On LabVIEW

As a kind of measuring the length and displacement of tools,the dial indicator is widely used to measure the geometric shape error and the position error. Due to the use of high frequency ,the dial indicator produce error easily. So the verification and correction of dial indicator appears very important . In the verification of dial indicator, displacement is critical. at present we always take precise diffraction grating sensor as its displacement benchmark. However, with the benchmark grating ,our vertification often using eye examination and manual feeding, its efficiency is not high. Based on the instructions of the instrument calibrator research status, developing a dial indicator at a low price and can reduce the metrological verification work strength, improve work efficiency has an important significance to the development of measuring and testing technology and improve measuring department verification ability and work efficiency.This topic use automatic feeding way approach instead of the past way.This system based on the LabVIEW software platform, taking the NI corporation's PCI-6014 multi-purpose data acquisition card as the connection between computer and exterior electric circuit, using half of the step-motor in automation and human eyes aim to achieve the aiming precision and the examination efficiency coordination. The system control section completes by the LabVIEW software, and the LabVIEW software controls the multi-purpose data acquisition card to send out the control pulse signal and to gather the diffraction grating ruler's counting data, taking the diffraction grating sensor as the displacement datum, then making comparison with the dial guage reading , extracts each erroneous value, in the end make the preservation. The data processing part according to the dial indicator examination regulations, shows the neighboring error, the value error, the entire journey error and the return trip error. The first six chapters detail the dial indicator design theory and method of each part,Finally in the chapter seven ,concluded that the system hardware and software test dial indicator verification results and achieve the performance index. Proposed the work we need to do if we want to upgrades and improve the dial indicator verification system.The first chapter introduces the design method , the target of subject and the background. LABVIEW software is introduced in this software, the advantages and disadvantages of the software are analyzed. Summarized the research situation dial indicator verification .Also, the first chapter introduces the significance of this research. Finally expounds the content of this research.In the Chapter second , the calibration overall design scheme of dial indicator verification system is proposed. According to the relevant provisions in China standard and specifications,this Chapter puts forward the design ideas and verification of dial indicator design task. In this chapter we also introduces the dial indicator of mechanical structure, system hardware structure and system composition and principle. At the same time this chapter have a detailed analysis of the dial indicator verification system principle and specific verification method. The feasibility analysis of system are expounded in the end.The third chapter introduce the working principle of the stepping motor model and the technical index, the selection of stepping motor . The third chapter have a detailed introduces of the stepping motor control system, driver circuit design, step-motor controller design. Especially the pulse distributor is introduced in detail. In this chapter the D flip-flop and working principle of the circuit are introduced in detail too.In fourth chapter, the grating and regulate circuit are introduced. It also Introduces the grating measuring long development situation and future development trend. The effect of moire-fringe and grating measuring length principle are analyzed. the grating signal output and digital model are introduced. Finally introduced the Grating signal including resistance grating signal chain, four in five subdivision instability in the circuit between fine detail.The fifth chapter introduces the software. The basic characteristics of the data acquisition card, data collection function is introduced in detail.the software channel configuration, analog signal output program design, and digital signal input and output, the program design, data counter displays and save them online are described in detail. In this chapter, we have a detailed instruction of analog signal output function, digital signal output function, digital signal input function and least-square method of fitting function modules and functions do port.The sixth chapter design the data processing and reporting procedures. In this chapter we first introduced the data call. Mainly introduces the function and read the documentation function indices. then ,We introduce the adjacent error, error, error and hysterisis error software design. Their software design flow chart are listed.In the seven chapter, we have an analysis of system error and have a test of hardware and software. We introduces the error sources and synthesis of system error. The results of the hardware and software test are analyzed. In the end we have a Conclusion that the system hardware and software design achieve the expected effect. Finally, we concluded that the verification of us belongs to grade 1.