Sensorfusion för undervattensrobot i kärnteknisk miljö med Kalman filtrering

Sammanfattning: WesDyne TRC AB is a fully owned subsidiary of the global Westinghouse Electric Corporation. WesDyne is a world leader in non-invasive methods for the inspection of nuclear power plants. One of the inspection platforms used to scan for defects in and around the welds in the reactor vessel is called the T-crawler. The T-crawler operates under water in a radioactive environment by stepping on the vessel (reactor tank) inner wall using suction cups. The environment is harsh and many traditional positioning sensors are not suitable for implementation. This thesis investigates the possibility to use a gyroscope and a pressure sensor to create an alternative and independent positioning system. Together with the current positioning sensors the new sensors will be fused in a Kalman filter. The Kalman filter together with the alternative positioning system will be evaluated using simulated sensors in Matlab. The thesis shows that a positioning system with a pressure sensor and a gyroscope is suitable for implementation on the Tcrawler, but the thesis also establishes that further testing is needed to fully evaluate the performance of the alternative positioning during a safety inspection. Acknowledgements Thanks to the people at WesDyne for the help and information during the thesis, especially Lars Skoglund my supervisor, David Seery for information about the Tcrawler and David Stenman for information about radiation and proofreading the report. Also I would like to thank friends and family for moral support during the thesis.