In the electrified railway power supply system, electric locomotive obtains power from the catenary's wire through the
pantograph. Under the action of the pantograph, combined with various factors such as vibration, touch current, relative
sliding speed, load, etc, the contact wire will produce mechanical wear and electrical wear. Thus, in electrified railway
construction and daily operations, the geometric parameters such as line height, pull value, the width of wear surface
must be under real-timely and non-contact detection. On the one hand, the safe operation of electric railways will be
guaranteed; on the other hand, the wire endurance will be extended, and operating costs reduced. Based on the
characteristics of the worn wires' image signal, the binocular stereo vision technology was applied for measurement of
contact wire geometry parameters, a mathematical model of measurement of geometric parameters was derived, and the
boundaries of the wound wire abrasion-point value were extracted by means of sub-pixel edge detection method based
on the LOG operator with the least-squares fitting, thus measurements of the wire geometry parameters were realized.
Principles were demonstrated through simulation experiments, and the experimental results show that the detection
methods presented in this paper for measuring the accuracy, efficiency and convenience, etc. are close to or superior to
the traditional measurements, which has laid a good foundation for the measurement system of geometric parameters for
the contact wire of the development of binocular vision.