MARWIN is a mobile autonomous robot platform designed for performing maintenance and inspection tasks alongside the European XFEL accelerator installation in operation in Hamburg, Germany. It consists of a 4-wheel drive chassis and a manipulator arm. Due to the unique Mecanum drive technology in combination with the manipulator arm the whole robot provides three degrees of freedom. MARWIN can be operated in a pre-configured autonomous as well as a remotely controlled mode. Its operation can be supervised through various cameras. The primary use case of MARWIN is measuring radiation fields. For this purpose MARWIN is equipped with both a mobile Geiger-Mueller tube mounted at the tip of the manipulator arm and a stationary multi-purpose radiation detector attached to the robot’s chassis. This paper describes the mechanical and electrical setup of the existing prototype, the architecture and implementation of the controls routines, the strategy implemented to handle radiation-triggered malfunctions, and the energy management. In addition, it reports on recent operations experiences, envisaged improvements and further use cases.