Transmission Line Inspection Research Articles

Unmanned Aerial Patrol Technology Based on Tracking Algorithm of Target Tracking

In order to study the power patrol technology of unmanned aerial vehicle, the tracking algorithm was applied. The automatic patrolling of power lines was discussed in terms of algorithms. An unmanned aerial vehicle transmission line inspection method based on machine vision was proposed. The image and video of the unmanned aerial vehicle inspection of the power line had a complex background. By Wiener filtering de-noising and probability density functions, the image clarity was improved. According to the existing tracking techniques and algorithms, a Camshaft target tracking algorithm based on lossless Kalman filter was proposed. The method of non-destructive Kalman filter was adopted to predict the region of interest of power line identification. Using the Camshaft algorithm, the prediction of the window was searched and the size of the window was adjusted. Transmission lines were tracked in real time. The results showed that the restoration effect of the algorithm was obvious. The clarity of the image was improved. It prepared for the extraction and tracking of the future transmission lines. Therefore, the proposed method provides a feasible way for the UAV power line inspection technology based on machine vision.

A random chemical reaction optimization algorithm based on dual containers strategy for multi‐rotor UAV path planning in transmission line inspection

SummaryAiming at the specific mission requirements of high‐voltage transmission line inspection, a modeling method based on columnar space is proposed, which simplifies the complexity of traditional methods to a certain extent, and ensures enough modeling accuracy. Then, an improved random chemical reaction algorithm based on dual container strategy (RMCRO) is proposed, and the new algorithm divides the set of molecules into two subsets and puts them into two reaction containers, respectively. A subset introducing PSO algorithm strategy strengthens the strategy of diversity algorithm molecules and enhances the global search capability of the algorithm. Additionally, another subset introducing elitist selection and differential strategy strengthens the local search ability of the algorithm and accelerates the convergence speed. Then, through the exchange of the two subsets under certain conditions, the advantages of the two subsets can be further integrated to eliminate the original defects. Finally, respectively analyze the simulation of two typical scenarios of transmission line inspection based on multi‐rotor UAV, the simulation results show that the proposed algorithm can avoid the local minimum, the path planning is shorter, and it can make the airborne camera equipment working in a more stable state.

Multi-Robot Cyber Physical System for Sensing Environmental Variables of Transmission Line.

The normal operation of a power grid largely depends on the effective monitoring and maintenance of transmission lines, which is a process that has many challenges. The traditional method of the manual or remote inspection of transmission lines is time-consuming, laborious, and inefficient. To address this problem, a novel method has been proposed for the Multi-Robot Cyber Physical System (MRCPS) of a power grid based on inspection robots, a wireless sensor network (WSN), and multi-agent theory to achieve a low-cost, efficient, fault-tolerant, and remote monitoring of power grids. For the sake of an effective monitoring system for smart grids, the very research is conducted focusing on designing a methodology that will realize the efficient, fault-tolerant, and financial balance of a multi-robot team for monitoring transmission lines. Multiple testing scenarios are performed, in which various aspects are explored so as to determine the optimal parameters balancing team performance and financial cost. Furthermore, multi-robot team communication and navigation control in smart grid environments are introduced.

A New Fusion Chemical Reaction Optimization Algorithm Based on Random Molecules for Multi-Rotor UAV Path Planning in Transmission Line Inspection

A fusion chemical reaction optimization algorithm based on random molecules (RMCRO) is proposed to meet the special demand of power transmission line inspection. This new algorithm improves the shortcomings of chemical reaction algorithm by merging the idea of repellent-attractant rule and accelerates convergence by using difference algorithm. The molecules in this algorithm avoid obstacles and search optimal path of transmission line inspection by using sensors on multi-rotor unmanned aerial vehicle (UAV). The option of optimal path is based on potential energy of molecules and cost function without repeated parameter adjustment and complicated computation. By compared with an improved particle swarm optimization (IMPSO) in different circumstances of simulation, it can be concluded that the new algorithm presented not only can obtain more optimal path and avoid to trap in local minimum, but also can keep related sensors in a more stable status.

Transmission Line Unmanned Aerial Vehicle Obstacle Avoidance System Incorporating Multiple Sensing Technologies

UAVs have been used in a large number of applications in transmission line inspections and job monitoring. Infrared detection perception, ultrasonic radar, visual recognition and other perception technologies are integrated into the obstacle perception of UAVs, adding a variety of obstacle detection methods to the UAV, enabling inductive transmission line equipment without dead angles to be detected early. Line equipment and devices in front of man-machine, and can reasonably perform obstacle avoidance operations, effectively reduce the collision accident between UAVs and lines, and improve the safety and reliability of unmanned aerial vehicles on transmission line inspection work, and ensure transmission lines operational safety has a very important role.

Context Semantics for Small Target Detection in Large-Field Images with Two Cascaded Faster R-CNNs

Computer vision and image processing techniques have been widely applied to power transmission line inspection. However, the successful detection of small targets in large scenes is still challenging due to their low resolution and poor feature representation. Existing methods, such as multi-scale image pyramid, multi-scale feature pyramid and multiple heterogeneous feature fusion, etc. can extract more representative features of small objects, but they usually require high computation cost. In this paper, we propose an effective two cascaded Faster R-CNN strategy, which is based on multi-scale features and semantic information between the objects and the background, to address the small target detection in large scenes. Specially, we detect large object candidate proposals that may contain small objects at first and then map them to the original images to detect the small-sized targets on the high resolution regions. Experiments show that our strategy could lead to higher (83.0%) accuracy of small target detection and recognition than the one-stage Faster R-CNN (78.3%) on the dataset of aerial images.

A Finite State Machine Based Adaptive Mission Control of Mini Aerial Vehicle

This paper describes a finite state machine for adaptive mission control of mini aerial vehicles. The purpose of a finite state machine is to support mission control during aerial inspection of high voltage transmission lines and insulators independently from environmental and other conditions. One of the basic application of our mini aerial vehicle research is inspection of high voltage transmission lines during its load mode. Around high voltage transmission lines and towers generating a strong electromagnetic field. An electromagnetic fields can be influence negatively to autonomous flight and mission control should be predicted such us situation to avoid possible accident.
 Moreover environmental and weather condition always unpredictable and mission control have to adapt for various type of additional constrains which can be make problem for pre-defined mission map and trajectory.
 Therefore, it needs to develop mission control for autonomous flight with an adaptive option or capability. Such mission control provides less workload and safety guarantee for the inspection team during the process.

Design and implementation for integrated UAV multi-spectral inspection system

In order to improve the working efficiency of the transmission line inspection and reduce the labour intensity of the inspectors, this paper presents an Unmanned Aerial Vehicle (UAV) inspection system architecture for the transmission line inspection. In this document, the light-duty design for different inspection equipment and processing terminals is completed. It presents the reference design for the information-processing terminal, supporting the inspection and interactive equipment accessing, and obtains all performance indicators of the inspection information processing through the tests. Practical application shows that the UAV inspection system supports access and management of different types of mainstream fault detection equipment, and can implement the independent diagnosis of the detected information to generate inspection reports in line with industry norms, which can meet the fast, timely, and efficient requirements for the power line inspection work.

A Novel Method of Autonomous Inspection for Transmission Line based on Cable Inspection Robot LiDAR Data

With the growth of the national economy, there is increasing demand for electricity, which forces transmission line corridors to become structurally complicated and extend to complex environments (e.g., mountains, forests). It is a great challenge to inspect transmission line in these regions. To address these difficulties, a novel method of autonomous inspection for transmission line is proposed based on cable inspection robot (CIR) LiDAR data, which mainly includes two steps: preliminary inspection and autonomous inspection. In preliminary inspection, the position and orientation system (POS) data is used for original point cloud dividing, ground point filtering, and structured partition. A hierarchical classification strategy is established to identify the classes and positions of the abnormal points. In autonomous inspection, CIR can autonomously reach the specified points through inspection planning. These inspection targets are imaged with PTZ (pan, tilt, zoom) cameras by coordinate transformation. The feasibility and effectiveness of the proposed method are verified by test site experiments and actual line experiments, respectively. The proposed method greatly reduces manpower and improves inspection accuracy, providing a theoretical basis for intelligent inspection of transmission lines in the future.

Numerical Calculation and Analysis on the Surface Electric Field Characteristics of Hot-Line Robot

Hot-Line robot (HLR) is an automatic transmission line inspection device developed in recent years. The mounting device should be contacted with the high voltage transmission line thus to realize the voltage transfer at the first operation stage of the HLR, and the HLR device which is regarded as a floating electrode might be damaged by discharge induced by the filed distortion during the voltage transfer process. The surface electric field of HLR device is optimized to improve its operation reliability, and a static-electric field finite element model of the transmission line which includes the HLR device is developed in this paper, and the dynamic surface electric filed characteristics of HLR during elevating operation process are studied by the finite elements model. Results show that influenced by the electric field which induced by high-voltage transmission line, the induced electric field can be generated on the surface of HLR during the process of elevating operation. The induced electric field distorts on the edge chamfer of HLR device which is regarded as a floating electrode. The maximum field strength position is influenced by the arrangement of the overhead wire conductor, and the edge chamfers are the key points of the electric field optimization of the HLR. The results of this study could provide theoretical basis and technical support for the optimization of HLR insulation characteristics, which is of great value to improve its operation reliability.

直升机3D激光扫描技术在架空输电线路巡检中的应用

本文介绍了直升机3D激光扫描技术，并将其应用到国网北京公司某500kV架空输电线路巡检中，通过获取的输电线路走廊的高密度、高精度激光点云和光学影像数据，实现输电线路本体及周围环境的三维建模、线路瞬时工况安全距离检测、线路不同工况安全距离分析以及平断面图输出，进而给出实时工况安全距离危险点分析报告，为线路安全维护提供可靠信息。 This paper introduces the technology of helicopter 3D laser scanning and the application to the inspection of a 500kV overhead transmission line in Beijing. By obtaining high density, high precision laser point clouds and optical image data in the transmission line corridor, it can realize3D modeling, safety test of line instantaneous under working condition, safety distance analysis under different working conditions and output of plane section, of transmission line and surrounding environment. Then the risk point report of the safety distance analysis under real time working condition is given, which provides reliable information for the maintenance of line safety.

Design and Development of Three Arms Transmission Line Inspection Robot

Design and Development of Three Arms Transmission Line Inspection Robot

输电线巡检机器人弱光条件下的障碍物识别研究

输电线巡检机器人弱光条件下的障碍物识别研究

Research on the control system of an amphibious transmission line Inspection UAV based on fuzzy PID control

The amphibious UAV combines the advantages of multi rotor UAV and line inspection robot. It can carry out two working modes: air flight and online driving. It can observe the running state of transmission line and improve the quality of patrol. In this paper, a fuzzy PID control algorithm is proposed to make the amphibious UAV flight control more flexible and close to the transmission line, and the simulation and software control process design are carried out.

Vision-based autonomous navigation approach for unmanned aerial vehicle transmission-line inspection

This article presents an autonomous navigation approach based on a transmission tower for unmanned aerial vehicle (UAV) power line inspection. For this complex vision task, a perspective navigation model, which plays an important role in the description and analysis of the flight strategy, is introduced. Based on the proposed navigation model, valuable cues are excavated from a perspective image, which enhances the capability of the perception of three-dimensional direction and simultaneously improves the safety of intelligent inspection. Specifically, for robust and continuous localization of the transmission tower, a developed detecting-tracking visual strategy—comprised tower detection based on a faster region-based convolutional neural network and tower tracking by kernelized correlation filters—is presented. Further, segmentation by fully convolutional networks is applied to the extraction of transmission lines, from which the vanishing point (VP), an important basis for determining the flight heading, can be obtained. For more robust navigation, the designed scheme addresses the scenario of a nonexistent VP. Finally, the proposed navigation approach and constructed UAV platform were evaluated in a practical environment and achieved satisfactory results. To the best of our knowledge, this article marks the first time that a navigation approach based on a transmission tower is proposed and implemented.

A generation method of insulator region proposals based on edge boxes

High-quality insulator region proposals play important roles in the process of transmission line inspection images. A generation method of insulator region proposals based on edge boxes is proposed in this paper, and edge boxes are applied to the localization of insulators in inspection images creatively. We take a series of operations to generate insulator region proposals: K-means cluster is used on curvature scale space (CSS) points extracted from edge images, the most appropriate cluster number is chosen, and the circle is drawn on the insulator subclass. We consider the characteristics of insulators’ edge images, and combine these characteristics with edge boxes. As a result, more insulator region proposals are displayed. The experimental results show that our method can effectively reduce the interference area, meanwhile, has high quality of region proposals with fast calculation speed.

Information and communication architecture for transmission power line inspections using unmanned aircraft system

The inspection of the transmission lines in the Brazilian electrical system, given the continental dimensions of the country, is a task of a high complexity. The search for technological alternatives that satisfy the need for fast, safe and reliable transmission lines inspection is something that has been sought by the entire sector. This study presents the architecture of a management system using unmanned aircrafts for transmission lines inspection. The proposed architecture in the scope of a project for Celesc Distribuição – Brazil shows the sub-systems integration such as mission planning and execution, data transmission, image processing and flight control. The architecture was verified by the main project stakeholders and simulation systems in the aeronautics area showing to be strong and safe for the execution of transmission lines inspection.

A novel 110 kV power line inspection robot and its climbing ability analysis

A novel mechanism for 110 kV power transmission line inspection is presented according to the requirements of inspection tasks and characteristics of obstacles on power transmission lines. Its conf...

Method of Slipping Identification and Control for the Driving Wheel of a High Voltage Transmission Line Inspection Robot

When the inspection robot runs on the overhead transmission line, self-adaptive climbing ability is an important index to estimate the robot application to real complex conditions, especially in the mountainous areas. The slipping of driving wheel usually happens when the robot climbs the lines with slopes, which would increase the abrasion of the driving wheel, reduce the efficiency of operation and waste the energy. So it is important to develop the wheels slipping identification and control method to improve the climbing ability of the inspection robot. This paper proposed a self-adaptive slipping identification and control method aiming to solve the slipping problem of the driving wheels. Firstly, the mechanism and force situation of the robot has been analyzed when the wheel slipping happens. Then we discussed the major factors to control the robot slipping and developed a dynamic model to identify the wheel slipping. Finally, we proposed a slipping identification strategy and a fuzzy control-based slipping control method. This slipping identification and control method have been tested by the experimental and practical field experiments to make the robot run in the experimental lines and the high voltage transmission lines (HVTL) in real, respectively. The performance results indicate that the proposed method is effective to improve the robot self-adaptive capacity to climb on the lines with slope and enhance the autonomous climbing and running ability of the robot.

UAV-Based Oblique Photogrammetry for Outdoor Data Acquisition and Offsite Visual Inspection of Transmission Line

Regular inspection of transmission lines is an essential work, which has been implemented by either labor intensive or very expensive approaches. 3D reconstruction could be an alternative solution to satisfy the need for accurate and low cost inspection. This paper exploits the use of an unmanned aerial vehicle (UAV) for outdoor data acquisition and conducts accuracy assessment tests to explore potential usage for offsite inspection of transmission lines. Firstly, an oblique photogrammetric system, integrating with a cheap double-camera imaging system, an onboard dual-frequency GNSS (Global Navigation Satellite System) receiver and a ground master GNSS station in fixed position, is designed to acquire images with ground resolutions better than 3 cm. Secondly, an image orientation method, considering oblique imaging geometry of the dual-camera system, is applied to detect enough tie-points to construct stable image connection in both along-track and across-track directions. To achieve the best geo-referencing accuracy and evaluate model measurement precision, signalized ground control points (GCPs) and model key points have been surveyed. Finally, accuracy assessment tests, including absolute orientation precision and relative model precision, have been conducted with different GCP configurations. Experiments show that images captured by the designed photogrammetric system contain enough information of power pylons from different viewpoints. Quantitative assessment demonstrates that, with fewer GCPs for image orientation, the absolute and relative accuracies of image orientation and model measurement are better than 0.3 and 0.2 m, respectively. For regular inspection of transmission lines, the proposed solution can to some extent be an alternative method with competitive accuracy, lower operational complexity and considerable gains in economic cost.