Ebru Karakose

A new computer vision approach for active pantograph control

Railway vehicles have become a modern transport media day by day. With the development of high-speed trains, this transportation way has been widely used for the transportation of people and cargo. However, several fault type in the pantograph-catenary system affects the performance of the train. Contact between a pantograph and catenary must slide along train movement. A sufficient lifting force should be applied to the contact wire when train moves. Vibrations occurred between a pantograph and catenary system and oscillations of contact wire cause the loss of contact. So, burst of arcing occurs in contact point. In this study, a new computer vision based method is proposed to control the contact force. The proposed algorithm utilizes the edge detection and Hough transform for detection of pantograph height. The obtained height is given to the control algorithm and the height of the pantograph is adjusted. The proposed method is verified by using a video taken from real pantograph and efficient results has been obtained.

A New Experimental Approach Using Image Processing-Based Tracking for an Efficient Fault Diagnosis in Pantograph–Catenary Systems

The periodical maintenance of railway systems is very important in terms of maintaining safe and comfortable transportation. In particular, the monitoring and diagnosis of faults in the pantograph catenary system are required to provide a transmission from the catenary line to the electric energy locomotive. Surface wear that is caused by the interaction between the pantograph and catenary and nonuniform distribution on the surface of a pantograph of the contact points can cause serious accidents. In this paper, a novel approach is proposed for image processing-based monitoring and fault diagnosis in terms of the interaction and contact points between the pantograph and catenary in a moving train. For this purpose, the proposed method consists of two stages. In the first stage, the pantograph catenary interaction has been modeled; the simulation results were given a failure analysis with a variety of scenarios. In the second stage, the contact points between the pantograph and catenary were detected and implemented in real time with image processing algorithms using actual video images. The pantograph surface for a fault analysis was divided into three regions: safe, dangerous, and fault. The fault analysis of the system was presented using the number of contact points in each region. The experimental results demonstrate the effectiveness, applicability, and performance of the proposed approach.

An investigation of pantograph parameter effects for pantograph-catenary systems

The pantograph and the catenary perform the current collection process in electrical railway systems. In such systems, the main purpose is to improve the quality of current collection. Many factors and parameters can affect the interaction between the pantograph and the catenary. Internal or external factors affect the dynamic behavior of the system and lead to parameter variations. In practical applications, the system parameters can be changed very quickly. Therefore, the sensitivity of the system corresponding to the parameter variations is very important. In this study, the effects of parameter variations of pantograph on the system were investigated for the pantograph-catenary system. The system response caused by the parameter variations was examined for a constant reference contact force. Simulation studies were performed in Matlab-Simulink. The new transfer function was obtained by keeping the other parameters fixed in each parameter variation. The simulation result obtained by the new transfer function was compared with the simulation result of reference value. A parameter variation impact on the system response was also interpreted by comparing it with other parameter variations. After analyzing the effects of parameters on the system response, modeling can be accomplished by determining the appropriate control techniques. However, instead of setting the controller parameters for each parameter variation, the use of active control techniques would be more appropriate.

An Analysis Approach for Condition Monitoring and Fault Diagnosis in Pantograph-Catenary System

High-speed trains have a great importance for long distances. The electrical energy for trains must be continuous and uninterrupted. So, the interaction and the mechanical contact between the pantograph and the catenary must be complete. Periodic condition monitoring, fault detection and pre-estimation are extremely important in the electrical railway systems. Therefore, in this study, a condition monitoring and fault diagnosis approach for pantograph-catenary system is proposed with improved model, control and analysis methods. There are two main aims of the study. The first is a regular monitoring of the system to determine whether any failure is occur. The second is to reveal the status of fault occurrence in the future. For this purpose, the contact point analysis between the pantograph strip and the catenary is performed. The most wearied points of the pantograph strip are defined by the method of condition monitoring.

A new arc detection method based on fuzzy logic using S-transform for pantograph–catenary systems

Abstractpantograph–catenary system is one of the critical components used in electrical trains. It ensures the transmission of the electrical energy to the train taken from the substation that is required for electrical trains. The condition monitoring and early diagnosis for pantograph–catenary systems are very important in terms of rail transport disruption. In this study, a new method is proposed for arc detection in the pantograph–catenary system based signal processing and S-transform. Arc detection and condition monitoring were achieved by using current signals received from a real pantograph–catenary system. Firstly, model based current data for pantograph–catenary system is obtained from Mayr arc model. The method with S-transform is developed by using this current data. Noises on the current signal are eliminated by applying a low pass filter to the current signal. The peak values of the noiseless signals are determined by taking absolute values of these signals in a certain frequency range. After the data of the peak points has been normalized, a new signal will be obtained by combining these points via a linear interpolation method. The frequency-time analysis was realized by applying S-transform on the signal obtained from peak values. Feature extraction that obtained by S-matrix was used in the fuzzy system. The current signal is detected the contdition as healthy or faulty by using the outputs of the fuzzy system. Furthermore the real-time processing of the proposed method is examined by applying to the current signal received from a locomotive.

Real-time condition monitoring approach of pantograph-catenary system using FPGA

In recent years, the importance of railway transport increases with the development of fast trains. Maintenance of this train should be performed at an early stage for safety and reliability. Because pantograph-catenary system is used to transmit the energy to the train in most of the electric trains, the early detection of the problems occurred in these systems are very important. In this study, an FPGA (Field Programmable Gate Arrays) based new fault detection method is proposed by using normal and thermal images. The method takes the images of pantograph-catenary system by a camera attached to the FPGA Kit and saves them to SDRAM and RAM blocks. Thresholding method is applied to image matrix read from SDRAM and occurred arcs are detected. On the other hand, the pantograph overhead bar is detected by applying sobel edge detection to the image read from RAM block. Arcs occurred in contact point is detected in real time by combining two methods. The proposed method is verified in a real experimental setup.

A navigation and reservation based smart parking platform using genetic optimization for smart cities

With the development of technology, smart devices are becoming more common in everyday life. The development of devices that can connect to the Internet and transmit data has been a source of inspiration for smart city designs. The common problem in our cities is the difficulty of finding free parking slots. The parking problem causes traffic to congest and people who go to work are looking for a place. In this study, a navigation and reservation based parking proposal system was developed for smart cities. The proposed method involves the development of small devices that send data to the internet using the internet of things (IoT) technology. The free parking space closest to the current location is found by genetic algorithm. The proposed method is tested for different scenarios and accurate results are obtained.

Performance evaluation of electrical transmission line detection and tracking algorithms based on image processing using UAV

Regular control of the electrical transmission lines is important in preventing unwanted accidents and power interruptions. It is very difficult to carry out this process involving the determination of the transmission line, the tower and the plants surrounding the transmission line with human power. Today, there are some studies that use unmanned aerial vehicles to control transmission lines. In this study, the performance evaluation of the algorithms required for monitoring and controlling the transmission lines with image processing is given by using unmanned aerial vehicles. For this, firstly the capabilities of the studies in the literature have been put forward and then inferences have been made on how to overcome the shortcomings of these studies. In addition, some application results on experimental images, necessary hardware architecture and algorithm structure to make line control healthy and highly accurate are given in detail. In particular, the examination of the required stability and control methods performances for the line control realization will contribute to the works in this area.