Purpose -The purpose of this paper is to describe the design and prototype implementation of the "Cable Crawler", a mobile teleoperated robot for the inspection of high-voltage power lines which rides on the topmost ground cable. By not being limited to just moving from mast to mast, it implements an innovative mechanism that allows for crossing a set of mast tops as well as smaller obstacles autonomously. Design/methodology/approach -After a brief overview of the state-of-the-art for this application, the basic concept of the robot is presentedwhich basically consists of a chassis and six motorized rubber-coated rollers, two in a horizontal position to take the weight and four vertical ones. The four vertical rollers are pressed onto the wire by springs, which guarantees slip-less propulsion in difficult situations. The detailed design of the most challenging components is presented, as well as the successful tests with the prototype. Findings -The feasibility of the concept is proven with a prototype implementation and successful test results. Practical implications -With a mass of 58 kg and only six drives, it consequently follows the industry's wish to have a robust, easy to maintain and rather cheap solution. Regarding the fields examined by the robot, the project concentrated on the detection of trees growing into proximity of the wires. Future work will mainly stress in further reducing the robot's mass and in facilitating its transport to the mast by the workers. Originality/value -The presented prototype allows for moving on the topmost ground cable of high-voltage power-lines and to passively roll over mast tops and smaller obstacles. With these properties, it is able to inspect long distances of cables in an autonomous way and by using a relatively low-cost and robust robot.

This paper presents the "Cable Crawler", a mobile teleoperated robot to inspect high voltage power lines. Its mechanism allows riding on the topmost ground cable of high voltage power lines and crossing a set of mast tips as well as smaller obstacles autonomously and thus is not limited to just move from mast to mast. The robot consists of an aluminium chassis, six propulsion units and two spaces for cameras and other electronic components. Six electrical motors drive independently six rubber-coated rollers, two in a horizontal position to take the weight and four vertical ones. The four vertical rollers are pressed onto the wire by springs, which guarantees slipless propulsion in difficult situations. A Matlab program controls the drives independently. An optical camera is mounted on the prototype, which can rotate 360° and the image can be transmitted wireless to the user's computer monitor. With a mass of 58 kg and only six drives it consequently follows the industry's wish to have a robust, easy to maintain and rather cheap solution. Regarding the fields examined by the robot, the project concentrated on the detection of trees growing into proximity of the wires.