  Autonomous robotic systems for various applications including transport,
mobile manipulation, and disaster response are becoming more and more complex.
Evaluating and analyzing such systems is challenging. Robotic competitions are
designed to benchmark complete robotic systems on complex state-of-the-art
tasks. Participants compete in defined scenarios under equal conditions. We
present our UGV solution developed for the Mohamed Bin Zayed International
Robotics Challenge 2020. Our hard- and software components to address the
challenge tasks of wall building and fire fighting are integrated into a fully
autonomous system. The robot consists of a wheeled omnidirectional base, a 6
DoF manipulator arm equipped with a magnetic gripper, a highly efficient
storage system to transport box-shaped objects, and a water spraying system to
fight fires. The robot perceives its environment using 3D LiDAR as well as RGB
and thermal camera-based perception modules, is capable of picking box-shaped
objects and constructing a pre-defined wall structure, as well as detecting and
localizing heat sources in order to extinguish potential fires. A high-level
planner solves the challenge tasks using the robot skills. We analyze and
discuss our successful participation during the MBZIRC 2020 finals, present
further experiments, and provide insights to our lessons learned.
