  The sewer inspection robot MAKRO is an autonomous multi-segment robot with
worm-like shape driven by wheels. It is currently under development in the
project MAKRO-PLUS. The robot has to navigate autonomously within sewer
systems. Its first tasks will be to take water probes, analyze it onboard, and
measure positions of manholes and pipes to detect polluted-loaded sewage and to
improve current maps of sewer systems. One of the challenging problems is the
controller software, which should enable the robot to navigate in the sewer
system and perform the inspection tasks autonomously, not inflicting any
self-damage. This paper focuses on the route planning and replanning aspect of
the robot. The robots software has four different levels, of which the planning
system is the highest level, and the remaining three are controller levels each
with a different degree of abstraction. The planner coordinates the sequence of
actions that are to be successively executed by the robot.
