Abstract: A robot device is provided, particularly for scaling vertical surfaces, comprising a frame structure 1 having four sides 2 to 5, preferably in a rectangular configuration, adjacent ends of each of the sides 2 to 5 being pivotally coupled together by pivots 6. Each of the side members 2 to 5 is provided with suction devices 7 associated with the pivots 6 thereof and a linear actuator 9 is provided between two adjacent sides which is sequentially controlled by a microprocessor to sequentially change the configuration of the frame structure 1 to effect travelling movement of the robot device.