A comparison between using distance sensors for measuring the pantograph vertically movement

In railway transportation the most important problem to solve consists in assuring the safety traffic of people and freight. In this scope some of the geometrical parameters regarding the contact line must be measured. One of this parameter is the pantograph vertically movement, so it must use distance sensors. Present paper studies the performance of two kinds of distance sensors, an ultrasonic distance sensor and an infrared sensor. The performances are studied from the point of view of error distance measurement and the possibility of using a real time acquisition system. The researches were made on a laboratory model for the pantograph realized at the scale 1:2. 1. General description of the application In order to measure the vertically movement of the laboratory pantograph, a hardware-software system is proposed. The system components are the followings and they are presented in Figure 1: -Laptop equipped with LabVIEW Development System NI MyRIO -Acquisition board NI MyRIO 1900, Xilinx processor, FPGA and Real time technology, 667MHz -LabVIEW application for programming and monitoring -Distance ultrasonic sensor Parallax Ping -Distance IR sensor Pololu -Temperature analogic sensor LM35 Figure 1. The block scheme of the application