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.

Machine learning models are increasingly being deployed in real-world contexts. However, systematic studies on their transferability to specific and critical applications are underrepresented in the research literature. An important example is visual anomaly detection (VAD) for robotic power line inspection. While existing VAD methods perform well in controlled environments, real-world scenarios present diverse and unexpected anomalies that current datasets fail to capture. To address this gap, we introduce CableInspect-AD, a high-quality, publicly available dataset created and annotated by domain experts from Hydro-Québec, a Canadian public utility. This dataset includes high-resolution images with challenging real-world anomalies, covering defects with varying severity levels. To address the challenges of collecting diverse anomalous and nominal examples for setting a detection threshold, we propose an enhancement to the celebrated PatchCore algorithm. This enhancement enables its use in scenarios with limited labeled data. We also present a comprehensive evaluation protocol based on cross-validation to assess models' performances. We evaluate our Enhanced-PatchCore for few-shot and many-shot detection, and Vision-Language Models for zero-shot detection. While promising, these models struggle to detect all anomalies, highlighting the dataset's value as a challenging benchmark for the broader research community. Project page: https://mila-iqia.github.io/cableinspect-ad/.

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.

Robotic platforms dedicated to powerline inspection are often complex to operate, take several minutes to cross any obstacle, and must be operated by highly trained specialists. To further its goal of massive inspection of its power grid, Hydro-Québec developed an innovative robot that is simple to operate and can be used directly by line maintenance technicians. LineRanger was developed following the field deployment of LineROVer and LineScout but aims at surpassing them in terms of inspection efficiency. With an ingenious and passive obstacle-crossing system, this new robot allows large-scale inspection of bundled-type powerlines, since the obstacle crossing time is considerably reduced. In this paper, details on the robot's key features are presented along with its mathematical analysis, which guarantees its stability on flexible bundles and directly influenced the design. Finally, the LineRanger prototype is presented, with insights about its first field deployments.

This paper presents the design of a multirotor unmanned aerial vehicle (UAV) capable of landing semiautomatically on a power line while carrying a payload. The vehicle then rolls along the line to perform an inspection. Special attention is given to the vehicle's onboard vision system, which consists of a monocular camera and LiDAR used together to compute the pose of the vehicle relative to the power line. Landing assistance is provided to the pilot by a position-based visual controller that aligns and keeps the vehicle centered along the power line. The pilot remains in control of vertical and longitudinal movement during descent. The proposed approach was tested on a full-scale test line and shows promise for future applications of high value to the electric industry such as non-destructive testing of power transmission lines.

This paper presents the characterization of the Hokuyo UTM-30LX laser range finder applied to obstacle detection on power line conductors. First, an overview section defines requirements and explains why the UTM-30LX was selected for this application. Next, since there is no published characterization of this particular sensor's performance, a comprehensive set of experiments is described, both general tests and ones specific to the novel problem of scanning a power line conductor to detect where obstructions are present. It is then explained how the LIDAR can be mounted on the LineScout power line robot and what algorithm is used to detect obstacles ahead. Basic results obtained on a full-scale power line mock-up clearly demonstrate the potential of the approach.

This video summarizes a breakthrough in the emerging field of transmission line inspection and maintenance robots. Collaboration between electric utilities recently led to a robotic inspection of a large ocean inlet crossing transmission line, performed by LineScout Technology. Key challenges associated with the live line inspection and crossing of the suspension clamp are presented. Some of the findings revealed along the spans are shown. The accompanying paper also discusses some of the features of the robotic system that were found essentials for the success of the task.

Power line inspection and maintenance practices are evolving as changing market regulations, significantly increased line loading and system availability requirements put pressure on grid owners to innovate. Robotics is thus making its debut in that field. Described in previous papers as an inspection tool, Hydro-Quebec LineScout technology is evolving into a teleoperated mobile robot capable of performing basic maintenance tasks. Programmable pan-and-tilt camera (PPTC) units were designed and implemented as the first step towards enhanced teleoperation control. LineArm, a dual end effector robotic arm, was specifically designed for work on bundled conductors. Design specifications and kinematics of these two subsystems are presented. Implemented application modules to be mounted on LineArm are also presented and their utilization is reported as a milestone in power line live maintenance. Lastly, future work and challenges in applying robotics to transmission line maintenance are briefly discussed.

Power line inspection and maintenance is a slowly but surely emerging field for robotics. This paper describes the control scheme implemented in LineScout technology, one of the first teleoperated obstacle crossing systems that has progressed to the stage of actually performing very-high-voltage power line jobs. Following a brief overview of the hardware and software architecture, key challenges associated with the objectives of achieving reliability, robustness and ease of operation are presented. The coordinated control through visual feedback of all motors needed for obstacle crossing calls for a coherent strategy, an effective graphical user interface and rules to ensure safe, predictable operation. Other features such as automatic weight balancing are introduced to lighten the workload and let the operator concentrate on inspecting power line components. Open architecture was considered for progressive improvements. The features required to succeed in making power line robots fully autonomous are also discussed.

Power line inspection and maintenance are fields of application where robotics has yet to be introduced. However, as in many other hostile environments, substantial benefits in terms of workers safety and quality of inspection results could arise. This paper describes one of the latest initiatives toward that goal by presenting the design of a teleoperated robot called the "LineScout". This moving platform has the capacity to cross obstacles found on the line. Special care was taken early in the design phase to account for the context of power utility operation and to customize the geometric parameters to the specific features of the electric power network. The final prototype incorporates several key mechanical design features, which are briefly described. The LineScout is now validated, fully tested and ready to undertake pilot projects.

This paper presents a new type of haptic device using spherical geometry. The basic idea of haptic devices is to provide users with feedback information on the motion and/or force that he or she generates. Haptic devices have several potential applications such as, for example, fine compliant assembly, VR environment simulation, and high-precision teleoperation, especially in hazardous or hostile areas. The particular architecture of the spherical haptic device developed here will be presented and its advantages will be highlighted. Then, its basic kinematic properties, which shall be used for control and geometric optimization purposes, will be reviewed. The design optimization itself will then highlight some important features of the mechanism. The control scheme and real-time force feedback issues will then be presented. Finally, the results obtained with the prototype will be discussed.