In cooperation with several French and German partners the Institut für Maschinenwesen im Baubetrieb is developing a manganese nodule mining system. The essential part of this mining system is a mobile collector to pick up manganese nodules in sea-depth of 5000 m and more. To guarantee high mobility, the collector is running on crawlers. To analyse their efficiency, several components of the collector, in the first place the pick-up mechanism and the crawlers were tested. A further task is the design and development of a controlling and automation system to operate the collector on the sea bottom. In working areas with difficult and unpredictable surface conditions, which cannot be programmed for controlled operation (open loop), a special path control by skid/slip control of the crawler (closed loop) will be provided.