高精度倾斜仪探头信号采集处理电路的设计

Design of signal acquisition and processing circuit for high precision inclinometer probe

为实现倾斜仪探头高线性度、高分辨率和高稳定度的角度测量要求,以石英挠性加速度计作为传感器,设计了一种以STM32为主控制器的倾斜仪探头信号采集处理电路,详细阐述了硬件设计和软件设计。加速度计感应到的重力加速度信号完成信号调理和A/D转换,对转换得到的数字信号进行倾斜角度解算、数字滤波和温度补偿后,通过D/A转换得到倾斜角度值(模拟电压信号)。经试验验证,该倾斜仪探头测量角度值的非线性偏差小于0.001°,分辨率达0.000 3°,最大温度漂移为0.010 9°。

To achieve excellent linearity , high resolution and superior stability of Inclinometer Probe , this paper designed a signal acquisition and processing circuit which used STM 32 as MCU for Inclinometer Probe ,while the silicon flextwre accelerometer was used as a sensor . In this article , hardware design and software design were introduced in detail .Signal conditioning and AD conversion were implemented for the acceleration of gravity signal from accelerometer .After calculation of the inclination , digital filtering , temperature compensation were used for the transformed data , DA conversion made the digital signal to be the value of inclination which was a voltage . In experiments ,the nonlinearity error is less than 0 .001° ,resolution reaches to 0 .000 3° and maximum temperature drift is 0 .010 9° about the measured angle value of the Inclinometer Probe .