基于MEMS传感器的旋转永磁体定位技术

Rotating Magnet Ranging Technology Based on MEMS Sensors

基于地磁场的随钻测量系统具有问题:进行轨迹拟合时存在误差积累;在地磁场受干扰时无法进行准确定位。使用永磁体进行定位可以消除以上问题。利用永磁体的磁场模型,建立了旋转永磁体定位模型,利用MATLAB对模型的数学特性进行了分析。提出了基于旋转永磁体的曲线拟合定位算法,并给出了算法实现流程。基于3轴MEMS加速度计和3轴MEMS磁阻传感器搭建了测量系统,并在实验室环境下进行了模拟实验,定位精度达到cm量级。

There are two main problems in the geomagnetic MWD （measurement while drilling）system, one is the accumulated errors in the track, the other is the azimuth error when the geomagnetic field is interfered with. The problems can be solved using a permanent magnet. The ranging model was established with a magnetic field model of permanent magnet. The mathematical features of the model were analyzed. A ranging algorithm used curve fitting was proposed based on the magnetic field model. A measurement unit was designed using a 3 - axis MEMS aceelerometer and a 3 - axis MEMS magnetoresistive sensor. A simulated experiment was done and an accuracy of centimeter order was achieved.