Research On Localization Technique Of Pipeline Robot Based On Ultra Low Frequency Electromagnetic Wave

In the applications of pipeline conveyance, the pipeline robot takes more important role in pipeline project, especially when the nondamage detection technique has a real application in pipeline industry. The localization of pipeline robot is a key technology which decides the application of robot in pipeline. Although the wired robot solution is now the main stream, its shortcomings, such as cable weight and signal attenuation, greatly limit its working distance. The normal electromagnetic technology can not be used in the pipeline robot localization for the steel shield. So the robot localization without cable is one of the key technologies to improve the system porformance and application level. Based on the projects"X-ray pipeline defect inspection robot"and"Seabed oil-conveying pipe inspection robot"supported by Chinese high-tech fund, this thesis presents a solution to mobile robot localization by using extreme low frequency(ELF) electromagnectic wave.The thesis reviews the development of pipeline robot and indicates the key application problems, such as localization technology, communication technology, and power supply technology. The exsited localization technology's merit and faults are analysed. As the ELF electromagnectic wave has the characteristics of penetrating different media, such as metal, soil, water, and sludge, the thesis studies an ELF electromagnetic wave-based localiztion method.The thesis establishes a normal localization model and presents two types of localication for pipeline robot, one is the autonomous localization and the other is the passive localization.Using anysis method of magetostatic field and Maxwell's electromagnetic theory, this thesis studies the ELF electromagnetic wave (23Hz) penetrability and builds the ELF electromagnetic transmission model, which descibes the physic performance of EFL electromagnetic wave transimission and simplifies the application.For the project"Pipe inspection robot"application, the thesis studies the multisensors-based localization problem. As the envirment of pipeline consists of seawater and sediment, the media's dielectric coefficient and magnetic...