We describe the method of calculation the force, which arise between the current collector of an electric train and the wire. Calculation is based on the video information from the TV camera placed on the locomotive roof. By digital processing the information, the time series are obtained, which represent time dependence of vertical coordinates of certain parts (the rack and the runner) of the current collector. Analysis of those series allow to reconstruct the real time dependence of the coordinates, to find the corresponding velocities and accelerations and, used the mathematical model of the current collector, to calculate the sought force as a function of time. The examples are given for such kind of calculations.

Mathematical modelling in actual problems of science and technics