Joachim Hertzberg and Frank Schönherr, GMD-SET
When inspecting sewers, it is required that discovered objects like damages or previously unknown laterals are entered into the existing sewer map at the correct metric position. On the other hand, odometry conditions in sewers can be very poor, and they may vary greatly with slip, slope, and sewage current. The paper describes a simple reasoning method for correcting the odometry error according to local conditions. The method is based on correcting past measurements, and hence the corresponding new map entries, according to safe localization points at individual landmarks and to a model of the local odometry error or errors in between the localization points. A sketch of the intended application of the method in an autonomous, multi-segment, articulated sewer robot is given.