Line Inspection Robot Research Articles

The Development of Underground Power Transmission Line Inspection Robot

The small underground power transmission Line inspection track robot is developed. The robot is composed of left and right track walking mechanisms driven independently and camera tripod head with better environmental adaptability and flexibility of movement. The robot is controlled by wireless remote control mode. The portable handheld controller is also developed with communication, control, display and storage function. The inspection work experiment at the cable room of 110kV underground substation has been done using this robot. The result indicates that the inspection robot has better flexibility of movement, better reliability of communication and better convenience of operation, which is the better method for underground power transmission Line inspection.

Conceptual design for transmission line inspection robot

Power transmission line is used for power distribution purposes due to their cost effective measure compared to underlying cable. However, prolonged exposure to natural weather may cause fatigue stress to the lines as well as induce material failure. Therefore, periodical line inspection is considered uttermost important as a preventive measure to avoid power outage. However, transmission line inspection has always been a high risk and expensive work. Hazardous works that may harm operator as well as routine that requires precise handling can be performed by robots. Various types of robots have been designed and developed for line inspection but only perform well on a straight and continuous line. As these robots encounter an obstacle during the inspection, then the real problem in terms of robot stability and smooth operation arises. In this paper, conceptual design and evaluation for transmission line inspection robot is presented. The inspection robot mobile robot must be able to bypass or avoid obstacles as it travels along the power transmission line.

Obstacle Navigation Planning for a Power Transmission Line Inspection Robot

According to locally autonomous and remote control modes for a power transmission line inspection robot, an FSM(finite state machine) based motion planning method for obstacle navigation is presented.The obstacle navigation processes of the inspection robot are divided into several key discrete states,and FSM models for motion planning are established.A fuzzy-based production system is offered for deducing obstacle navigation modes and producing the motion sequences.Simulation and field experiments prove that the motion planning method for obstacle navigation is correct and valid,and can be applied to motion control of the power transmission line inspection robot.

Detecting broken strands in transmission line - Part 1: Design of a smart eddy current transducer carried by inspection robot

SUMMARY Transmission line is the primary facility for power delivery and is mainly composed of twisted aluminum wires. During the long-term outer door field service, overhead transmission lines will encounter strikes of lightning, corrosion of chemical contaminants, ice shedding, wind vibration of conductors, lines galloping, damage due to external forces and so on which will generally bring a series of latent faults such as aluminum strands fracture. It will induce some fatal accidents such as broken transmission lines which have a very strong impact on the safe operation of power grids if the latent faults can not be recognized and restored as early as possible. The method of detecting broken strands in transmission line by inspection robot with detectors is a method with good prospect. In this paper, a kind of eddy current transducer (ECT) for detecting broken strands in transmission line is developed. The developed ECT can be integrated to the transmission line inspection robot. Simulation and field experiment results show that the magnitude field induced by transmission current has no influence on the detection of broken strands in transmission line. Hence, the developed ECT carried by robot can identify broken strands with high reliability and sensitivity. At the same time, the proposed structural style and design method of the ECT can be applied to different types of transmission line. Copyright © 2012 John Wiley & Sons, Ltd.

Induction Power Supply System for Power Transmission Line Inspection Robot

In order to prolong continuous working time of one transmission line inspection robot, a power supply system with induction charging unit for this inspection robot is introduced in this paper. Special current transformer by which the robot could get power from power line is designed according to the magnetic field condition around the transmission line. Besides, charging circuit for Li-battery pack is also introduced. A fly-back circuit is applied in the circuit to provide precisely accessible input power for charging battery packs. Experimental results show that the power supply system could have good performance on extending the continuous working period of the transmission line inspection robot.

Design and Analysis of Multi-Winding Power Current Transformer for Power Transmission Lines Inspection Robot

Special current transformer (CT) is designed to induct power from the power transmission lines for an inspection robot. Equivalent circuit is used for calculating and modelling the parameters of the current transformer. Air gap analysis is given aiming at adapting dynamic range of bar current, and calculation of the effect of air gap is provided in detail. Ratio change of current transformer is introduced by which the secondary current could be adaptive to the bus current. Simulation results show that dynamic control of length of air gap and turns of the coils could make the current transformer be adaptive to the variable bus current and be more convenient for inducing power for the power transmission lines inspection robot.

Research on Dynamic Characteristics of Serial-Parallel Combination Joint with Flexible-Cable

In order to design the humanoid dual-arms high voltage transmission line inspection robot, the robot model is given and the working mechanism of the robot crossing obstacles is introduced, and the motion trajectory of the robot when it is moving is analyzed. The dynamic equations of the serial driven and the serial-parallel driven robotic arm are presented based on Lagrange equation and the dynamic characteristics of the wrist and elbow joint are simulated. The numerical simulation result of the serial driven robotic arm shows that the elbow joint has great torque when the robot moves horizontally and vertically. However, the numerical simulation result of the serial-parallel driven robotic arm shows that the elbow joint torque reduces greatly comparing with the serial driven arm. By analyzing the results of the simulation experiment, it can be seen that this serial-parallel combination driven joint with flexible-cable can reduce the elbow torque greatly and improve the load capacity of robotic arm comparing with the serial driven joint, which can solve the problem that the torque of serial driven joint in dual-arms inspection robot is too high.

Human-Robot Interaction System Research for 500kV EHV Power Transmission Line Inspection Robot

An assisted and secure interaction system is developed for 500kV EHV Power Transmission Line Inspection Robot. The challenges on amenity, assistance and security of interactive operation are emphasized. Due to the unpredictable line structure and the incomplete sensory, the robot is controlled in remote and locally autonomous mode. Based on the Finite State Machine (FSM), the automatic crossing interface is designed for protecting operators from memorizing redundancy sequences. Measures for friendly operating and avoiding errors are concerned. The architectures for fully autonomous are also engaged. The lab and field experiments validated the interaction system reliable and easy to use.

다양한 센서를 이용한 배전선 점검 로봇의 높이 및 자세제어

A new wire detection algorithm for power line inspection by a mobile robot has been proposed in this paper. There have been a lot of studies in order to support the high-quality electric power. For the high-quality power supply, it is necessary to investigate the power lines and insulators before the lines or insulators were disconnected or damaged. Although Korea Electric power Corp. has made many efforts for the quality improvement, it is not enough to inspect all the power lines by human inspectors. According to this problem, it is decided to replace the human operators by the power line inspection robot. When the robots are used for the inspection, there could be several advantages, for example, the working efficiency and the prevention of accident. And also the shortage of human power for dangerous jobs can be resolved. In this paper, as a part of the development of power line inspection robot, DICRO, the sensor fusion and fuzzy control algorithms are developed to detect the wire and slope of the wire. The effectiveness of the proposed algorithms is proved by the real experiments with DICRO which is under development so far.

Image-based visual servoing for power transmission line inspection robot

This paper describes a vision-based system for a powerline inspection robot. The main emphasis of this paper is on an image-based visual servoing strategy for driving the robot arm toward a desired configuration in order to grasp the line. The method skips the step of transferring image features back to robot pose, and hence makes driving arm motion plans directly in the image plane, providing a 'visual' trajectory in the image plane for the gripper to track and locate the phase line and related obstacles in an effort to make the robot body to align with the phase line. A proportional control law with a dead zone is given to achieve the driving wheel and powerline alignment operation. Experimental results using an inspection robot platform are presented, showing that good servoing can be achieved using the proposed controller of the vision system.

Ferranti Mk. IV continuous path phase control system

Routine inspection of a power transmission line (PTL) system for early fault detection and maintenance is crucial for efficient transmission of electric power to consumers. Unlike the conventional manual inspection methods that are labor intensive, dangerous and expensive, an efficient inspection using robots has been a key research interest for many research institutes around the world. This paper presents a comprehensive review and trends of power transmission line inspection robots (PTLIRs) focusing on the latest research achievements within the years 2008 to 2019. The structure, operation, and limitations of the inspection robots, namely, climbing, flying, and hybrid (climbing-flying) robots are extensively discussed. Although climbing robots provides the most reliable inspection data due to their proximity to the line, landing the robot on the line as well as obstacle avoidance has been challenging. Thus, hybridizing the climbing and the flying robots have proved to be an excellent approach to the robotic PTL inspection. Furthermore, power supply, automatic obstacle detection, and control system which are the main challenges of PTL inspection are presented. Finally, it is has been concluded that challenges such as limited on-board battery capacity, unreliable line fault detection, electromagnetic shielding, de-icing mechanism and advanced control techniques for external wind disturbance would be a promising future research direction for researchers in the field of robotic PTL inspection.