Design Of A Multi-channel Vibration Signal Acquisition System Based On Zynq

Vibration signal acquisition plays a vital role in the diagnosis of rotating mechanical faults.Most of the low-cost vibration signal acquisition devices on the market have low resolution,more 12 bit,16bit,etc.The range of measurable frequency is relatively limited and the bandwidth is small.In this paper,a low-cost multi-channel vibration signal acquisition system is designed.By loading two ADC with different accuracy and sampling rate,the vibration signal acquisition and transmission of a total of ten channels can be completed.The main work contents are described as follows:1)Requirements analysis and overall scheme design.How to determine the parameters of the system according to the frequency of the mechanical vibration signal,and then analyze the problems to be solved in the design,and propose a solution to determine the system structure.2)Design of the signal conditioning circuit.According to the design requirements,the anti-aliasing filtering scheme is selected.When designing the analog filter,Sally-key active second-order low-pass filter is selected to filter the high-frequency noise to calculate the resistance and capacitance in the circuit.Finally,the simulation optimization was made with Multisim,so as to further complete PCB plate making.3)Design of the ADC acquisition circuit.According to the design requirements,two ADC are selected for signal acquisition,and the peripheral circuits are designed according to the corresponding datasheet to correctly communicate with Zynq;the power supply circuit is designed so that the 3.3V voltage can be converted to 5V voltage,and the PCB plate welding is finally completed..4)Program and design the signal acquisition and processing part at the PL terminal.Program the FPGA part in Vivado,and two ADC acquisition and control status machines are written according to the timing diagram.Through the two-port BRAM module,the ping-pong reading and writing operation mode is used to cache the data.Then,the scheduling module divides the data into two ways,and the original data and the data processed by FFT are transmitted to the PS terminal through DMA.5)PS terminal programming to achieve data storage and data transmission.The SDK software written by Vivado was used to realize the data DMA transmission,customize the data communication interaction protocol,and transmit the data to the upper computer through TCP according to the protocol.The upper computer software was developed to complete the data reception and make the corresponding waveform display.Finally,by carrying out experiments and collecting signals of different frequencies,the signals can be restored,and the signal acquisition of multiple frequency segments can be carried out under the premise of low cost.