Track gauge dynamic measurement based on 2d laser displacement sensor
Track irregularities can cause deterioation of riding comfort and derailment. Track gauge variation is one of the basic track irregularities. Track Recording Car is an automated track inspection vehicle on a rail transport system used to test several geometric parameters of the track. Track geomeotry parameters generally measured include position, speed, gauge, alignment, crosslevel, curvature and so on. This paper presents a novel technique for the measurement of track gauge variation, a new measurement system was introduced and been in assembled on a new type underground track recording car.
Detection of missing nuts & bolts on rail fishplate
In India human operator manually inspects the fishplates on railroads for any missing nut & bolt; broadly these inspections are based on visual analysis that might be prone to human errors, endangering passengers of the train. This paper is based on a machine vision approach that emulates the visual ability of human operator for the automation of the process. Digital im ages have been acquired of rail fishplates from both sides (left and right) of rail joint. A pattern recognition approach has been adopted for detecting the existence of nuts & bolts of fishplate at rail joints and thereby achieves automation. The number of nuts & bolts on fishplate, length, and width of the fishplate computed as features through discrete wavelet transform (DWT). The features evaluated relative to the database features and inference estimated in terms of the fitness of the fishplate. The effect of using DWT along with the similarity measure has been tested through performance metrics. Results obtained shows that the proposed approach has high reliability and robustness with less computational complexity.
Investigations of dielectric gratings using electrodynamic models based on volume integral equations
Eigenmodes of planar and cylindrical dielectric gratings (DGs) and electromagnetic wave scattering from multiplayer DGs are investigated. The DG characteristics are calculated using numerical-analytical solution of integral equations (IEs).