Software approach for the autonomous inspection robot MAKRO

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 is to take water probes, analyze them onboard, and measure positions of manholes and pipes to detect pollution loaded sewage and to improve current maps of sewer systems. One of the challenging problems is the control software, which should enable the robot to navigate in the sewer system and perform the inspection tasks autonomously, while always taking care of its own safety. Tests in our test environment and in a real sewer system show promising results. This paper focuses on the software approach. To manage the complexity a layered architecture has been chosen, each layer defining a different level of abstraction. After determining the abstraction levels, we use different methods for implementation. For the highest abstraction level a standard AI-planning algorithm is used. For the next level, finite state automata has been chosen. For "simple" task implementation we use a modular C++ based method (MCA2), which is also used on the lowest software level.