Powerline robotics is slowly becoming key tools for electric utilities. Contrary to drones that are usually limited to inspection tasks, wheeled robots like LineRanger can perform a broader range of applications. In this paper, a suite of mechanical devices is featured, as several new asset management tasks were recently added to LineRanger’s capabilities. While previous applications focused on non-contact inspection (visual, electro-magnetic, etc.), the new tasks at hand involved reaching adjacent conductors to probe line components with micro-Ohmmeter, installing and retrieving custom build sensors for multi-day line monitoring, and assessing aging conductors surface properties, to refine their thermal model and optimize the line capacity during heat waves. All three applications were recently field validated onto LineRanger, and mechanical design insights shall be presented for each module.

Even if UAVs undoubtedly had a profound effect on the visual inspection capabilities of transmission lines, rolling robots, especially for bundled configurations, will still play an extensive role in the maintenance of these strategic assets. As such, LineRanger is among the most efficient and capable wheeled platform, that can travel at an average speed of 8 km/h. In this paper, LineRanger mechanical design insights are shared, unfolding how strictly mechanical solutions deals with ease of obstacle crossing, ease of installation procedure without requiring any linemen to access the high voltage environment area, and ease of deployment of dedicated, custom-made sensors onto the line component of interest. This novel robotic platform is now being deployed onto Hydro-Quebec power grid network, performing high value applications.

In this paper, a slip-limiting controller for redundant line-suspended robots is presented. This kind of robot is usually equipped with v-shaped wheels, which brings uncertainty about the effective wheel radius, particularly when crossing obstacles. The proposed algorithm is able to estimate and limit wheel slippage in the presence of such uncertainty, relying only on wheel angular velocity measurements. Slip limitation occurs in the control allocation algorithm and hence is decoupled from the high-level velocity controller, allowing a broad applicability in centralized control approaches. Experimental results on Line Ranger show that it effectively reduces wheel slippage compared to traditional centralized control while being more energy efficient than traditional decentralized control approaches.