Design Of Multi-Channel Ultrasonic Automatic Testing System And Development Of Multi-Functional Module Based On PXI-Bus

The design of multi-channel automatic ultrasonic testing system based on PXI-Bus and development and implementation of multi-functional module based on PXI-Bus using in ultrasonic testing have great realistic significance for development and implementation of domestic multi-channel automatic ultrasonic testing system using in thicker steel plate. Based on the study PXI(PCI extensions for Instrumentation)-Bus norms and ultrasonic NDT(Non-Destructive Testing) familiar with the basic knowledge, the thesis proposed a multi-channel automatic ultrasonic testing system scheme used in NDT of thicker steel plate, and developed a multi-functional module based on PXI-Bus using in ultrasonic testing.Multi-channel automatic ultrasonic testing system based on PXI-Bus used the generic structure composed of ultrasonic testing equipment subsystem, electrical and control subsystem and mechanical servo subsystem. By summing up the characteristics of domestic and international system, the system designed with mixed networking way of PXI-Bus and IP-Bus. PXI-Bus with real-time property and higher reliability was used in the unit needing higher real-time requirements (ex. ultrasonic automatic flaw detection and processing unit). Open TCP/IP bus was used in data processing and form reporting. The scheme ensured real-time property and reliability of ultrasonic testing, and enhanced the system's expansibility and ease of maintenance.The thesis introduced the design and realization of a multi-functional module using in ultrasonic testing, which was based on PXI-bus interface and adopted FPGA used as the central logic control processing unit. The multi-function module was composed of several relevant independent functional units which were measuring velocity, surveillance of probe state, generating synchronous timing sequence, selecting testing acquisition channel and real-time transmission of data. Multi-functional module improved overall system integration and cooperation efficiency of system modules. The design of multi-functional module involved the PXI-interface circuit and functional circuit development, meanwhile fully considered the module reliability and expansibility. Practical applications showed that the multi-function modules achieved the anticipated design requirements and had the certain extended applications.