Outdoor robotic work tool and method for use in outdoor robotic work tool

The invention relates to an outdoor robotic work tool and a method for use in the outdoor robotic work tool. The outdoor robotic work tool is adapted for a forward travelling direction and comprises an environmental detection system that comprises a set of outer detector transceivers and a set of inner detector transceivers, where the inner detector transceivers are positioned between the outer detector transceivers. Each detector transceiver is adapted to transmit signals and to receive reflected signals that have been reflected by an object. The outer detector transceivers are associated with outer coverage main directions that are directed at corresponding outer angles to the forward travelling direction, and the inner detector transceivers are associated with inner coverage main directions that are directed at corresponding inner angles to the forward travelling direction. The inner angles have magnitudes that exceed the magnitudes of the outer angles, and the inner coverage main directions intersect in f