Development Of Solid Surface Velocity Laser Double Focus Cross-correlation Measurement System Based On FPGA

Non-contact measurement is an important topic in mechanical measuremants nowadays. With the development of industy and technology, it is becoming more and more important to realize and utilize the non-contact measurement principle and method in industry domain. Specially in recent twenty years, with the rapid development obtained in spaceflight, navigation, steel, spinning, paper making and micro-mechanism, our country has put forward further requests for non-contact measurement technology and instruments. The cross-correlation technology applyed to non-contact measurement has the special superiority. The cross-correlation technology for velocity measurement, as a non-invasive, non-contact and non-contaminative measurement technology, shows great advantages in industrial applications, such as steel, spinning, paper making, automobile and micro-electronics.Based on the research achievements obtained by our task team recently, this dissertation further employed digital signal processing and modern electronic technology into surface movement measurement. A solid surface velocity laser double focus correlation measurement system based on FPGA is developed, which is able to improve the precision and real-time performance of system. The main work is described as follows:1) The development history and the present development situation of non-contact movement measurement are summarized, and its theory and achievements are introduced in detail.2) The design and characters of optical sensor have been discussed in detail.3) The polarity cross-correlation algorithm to accelerate computation process of the system and the SOPC scheme of velocity measurement system based on FPGA are realized.4) A thorough test under laboratory condition on the surface movement velocity measurement system based on FPGA is implemented in this thesis. Compared to the other two velocity measurement systems(VelocityMeasurement System Based on Encoder and Virtual Instrument Velocity Measurement System Based on PCI Card), the performance, shortcomings and advantages of the system based on FPGA are drawn out. The result of experiment shows the system based on FPGA is applicable to the velocity measurement of solid surface movement.