Research On Trajectory Measurement Method Of Underground Equipment Based On Inertial Navigation

Underground equipment trajectory measurement is an important link in oil exploration and mining operations.Through the measurement of the trajectory of underground equipment,the location of underground equipment can be realized quickly,and the efficiency of exploration and mining operation is greatly improved,which is of great significance to the oil industry.However,there are some defects in the current trajectory measurement methods,which can not meet the trajectory measurement requirements of all oil well conditions.Therefore,it is urgent to study a down-hole trajectory measurement method that can suit most of the well conditions and solve the practical problems in the petroleum industry.In this paper,an inertial navigation method is proposed to solve the trajectory measurement of down-hole equipment in oil field.The method includes three parts:down-hole data acquisition device,communication module and ground trajectory calculation system.The acquisition device collects the inertial data in the movement with the equipment together with the equipment.After the movement ends,the acquisition device is raised to the ground,the inertial data is uploaded to the solution system through the communication module,and the calculation system is used to calculate the inertia number.According to the calculation,the equipment trajectory information is obtained,and the equipment trajectory is plotted in the three-dimensional coordinate system.This method can be applied to most existing oil wells,and independent of external devices to achieve trajectory measurement independently.In this paper,the modules of the acquisition device are selected,and the hardware design is completed,and the underground acquisition device is produced.On the basis of the hardware platform of the device,the C language program is written to obtain the acquisition,storage and data communication of the inertial data.Secondly,the handshake communication protocol based on asynchronous serial communication interface and the data management software based on VB are designed to realize the extraction of the down-hole inertial data.In the end,based on the basic algorithm of inertial navigation,the ground trajectory calculation system is designed to measure the trajectory information of the down-hole equipment,and the simulation verification is carried out.In view of the error of inertial device and the error of trajectory calculation,the data preprocessing algorithm and error compensation algorithm are used to compensate the error value of acceleration,angular velocity measurement and angle calculation respectively.It is proved by experiments that the data preprocessing and error compensation algorithm can improve the precision of trajectory measurement.And the ground simulation experiment and down-hole experiment are used to verify the trajectory measurement results.It is proved by experiment that the down-hole trajectory measurement function can be basically realized by this method.