Development And Instrumentation Of A Multitype Synchronized Signal Acquisition Instrument With The ZYNQ Platform

The structural health monitoring system can carry out real-time online monitoring of engineering structures,use the structural health diagnosis method to determine the location and degree of structural damage in real-time,and then evaluate its safety performance,predict structural changes and give early warning of dangerous situations.It is an effective means to ensure the safety of major engineering structures.The data acquisition subsystem of the structural health monitoring system can collect the relevant data of the sensor subsystem reflecting the current situation of structural health,which is the cornerstone of the structural health monitoring system.Major engineering structural health monitoring projects have the characteristics of large sensor capacity,many types,high synchronous acquisition accuracy,long-term stability,and strong real-time data acquisition and analysis.At present,a variety of data acquisition systems have been developed at home and abroad.The acquisition technology and acquisition scheme are constantly innovated,mainly towards the large capacity,many types,synchronous acquisition,and real-time analysis.Aiming at the monitoring requirements of large-scale,multi-type,and synchronous acquisition and comprehensive analysis of sensors in the health monitoring system of major engineering structures,this paper develops a multi-type synchronous signal acquisition instrument based on ZYNQ in which the user independently defines the type of signal collected by each channel,adopts a set of flexible system division mode,comprehensively utilizes the high-speed parallel computing ability of FPGA and the real-time control ability of ARM,realizes the synchronous acquisition of multiple types of sensing signals(bridge circuit,IEPE signal,voltage,and current sensing signal).And the instrument is successfully applied to the structural health monitoring test of the transmission tower.The specific research work of this paper is summarized as follows:(1)A multi-type sensor signal synchronous conditioning board based on AD7193 + RJ45 is developed,which makes comprehensive use of the channel configurability of the AD7193 chip and the scalability of the outgoing bridge box of the RJ45 interface.By manually replacing the sensor and the corresponding bridge box,designing the conditioning channel of each type of sensor signal,and setting the channel for AD conversion of AD chip,the synchronous acquisition and free switching of multiple types of sensing signals(bridge circuit,IEPE signal,voltage,and current sensing signal)are realized.(2)A multi-type synchronous signal acquisition instrument based on ZYNQ is developed.This paper uses the ZYNQ core board and develops a supporting data acquisition backplane that realizes the hardware interconnection with the multi-type sensing signal synchronous conditioning board;the FPGA side is responsible for data synchronous acquisition and performance parameter configuration of 16 channel AD chip,and realizes data interaction with ARM side using AXI DMA and AXI EMIF;the ARM end is responsible for data interaction with FPGA through configuring DMA and EMIF,and establishes UDP server through LWIP to realize data interaction with the host computer.(3)The graphical user interface(GUI)of the upper computer of the acquisition instrument based on C# is developed.The data interaction with the acquisition instrument is realized through UDP protocol;By setting the configuration interface,the user can independently define the type of sensing signal which is collected at each channel;Through the producer-consumer mode,the function of receiving and visualizing the data of the acquisition instrument is realized;By setting the local storage interface,the function of local storage according to specific needs is realized.(4)The multi-type synchronous signal acquisition instrument developed in this paper is applied to the transmission tower test.The strain sensor,acceleration sensor,and displacement sensor are installed on the transmission tower model for monitoring.And the displacement reconstruction is successfully realized.It is verified that the data acquisition instrument developed in this paper can meet the monitoring requirements of large-scale,multi-type,and synchronous acquisition and comprehensive analysis of sensors in the structural health monitoring system.