基于FPGA的压电式加速度计自动化校准系统研究

Automatic calibration system of piezoelectric accelerometer based on FPGA

压电式加速度计可实现冲击碰撞试验中瞬态高加速度值的采集,在振动冲击领域中被广泛应用。为实现压电式加速度计性能的快速、准确校准,研制一种基于可编程阵列逻辑(FPGA)的自动化校准系统,并利用高级图形语言LABVIEW进行软件设计。自动化校准系统基于现有计量校准系统进行研制,采用了冲击激励法校准原理。在原有系统的基础上附加自动化机电控制系统,冲击用压缩气体的压力由上位机设定,经由基于FPGA的电控系统后,对电动旋转机构进行控制,实现气压的自动调节,气压稳定后开始冲击实验并自动记录实验数据。与传统仪器相比,论文所研制系统可实现更快速、更简便、更准确的压电式加速度计校准。

Piezoelectric accelerometer can be used to measure the transient high acceleration value in impact crash test,and it is widely used in the field of vibration and shock.In this article,an automatic calibration system based on programmable array logic(FPGA)is developed,and the software by using high-level graphic language LABVIEW is designed.The developed system can realize the fast and accurate calibration of the piezoelectric accelerometer.The automatic calibration system is improved based on the existing measurement calibration system,which adopts the principle of shock excitation method.We attached an automatic electromechanical control system on the basis of the original system.The pressure of the compressed gas for shock excitation is set by the computer,and after the operation by the electronic control system based on FPGA,the electric rotating mechanism is controlled to realize the automatic adjustment of the air pressure.Then,when the pressure is stable,the calibration test will be start and the experimental data will be recorded automatically.Compared with the traditional instruments,the proposed system can achieve faster,simpler and more accurate calibration of piezoelectric accelerometer.