Research On The Positioning Technology Of Small-diameter Remotely Operated Pig In Urban Area

With the gradual improvement of urban infrastructure construction,the construction of underground footpath pipeline is also more and more complex,drainage,sewage,oil and gas transmission pipelines criss-cross.Among them,underground small-diameter pipeline(D<30cm)takes up a large proportion in the city.Although the pipeline facilities are very advanced,the daily integrity management and maintenance of urban underground pipelines are always facing many difficulties.Because most urban pipelines are buried deep underground,it is difficult to locate and maintain the defects(cracks,corrosion,depressions,etc.)of pipelines.Based on the above issues with cable pipeline inspection robot for the platform,the Micro Inertial Measurement Unit(MIMU)combined with odometer build auxiliary pipeline defect detection positioning Micro Inertial Measurement system,and combining with the pipe connector connect straight pipe section for this important features to further improve the positioning accuracy,the main research content is as follows:First of all,the research and analysis of pipeline robot and its positioning technology research status at home and abroad,combined with the existing path pipeline robot detection platform,pipeline design based on the combination of MIMU/odometer path positioning system overall scheme,a simplified inertial sensor algorithm of strapdown navigation system for micro inertial measurement system information,comparative analysis the RISS algorithm for calculating the global marketing advantage,finally the simulation analysis proves the feasibility of RISS navigation algorithm.Secondly,the overall scheme design and implementation of the micro-inertial measurement module hardware system are carried out.STM32 single-chip microcomputer was used to build the circuit system,and the circuit board was designed in combination with the pipe size in the test platform,and the bottom drive of the hardware system was completed,so as to realize the data acquisition of MIMU and oommeter sensors.At the same time,MIMU and odometer data are stored in SD card by file system.Finally,the data results are analyzed with the host computer software offline.Next,the combined positioning technology of the MIMU/ odometer/pipe connector framework is studied.Firstly,the algorithm and model of Kalman filter are briefly introduced.Secondly,the importance of pipeline connector detection for system positioning is analyzed.The frequency characteristics of pipeline connector in IMU original data accelerometer are analyzed by means of the complex continuous wavelet transform modulus maximum method,and the corresponding time period of each pipeline connector is collected by setting a fixed threshold.Finally,the filter update model of integrated navigation system is designed based on KF and pipeline characteristics.Finally,the experiment platform of the small-path cable-controlled pipeline robot is built and the combined positioning algorithm is verified.The simulation builds the real experiment environment of the small path pipeline,installs the overall equipment of the experiment,designs the test route of the pipeline robot,and verifies the accuracy and rationality of the overall design of the small path cable-controlled pipeline detection robot positioning system.