On flight routes at altitudes from tens to hundreds of meters (over mountainous terrain), electric power lines (EPLs) are a serious cause of emergency or even disastrous situations for light- and medium-payload low-speed airplanes and helicopters, especially at night and in daytime during poor weather conditions.

Previous attempts to provide helicopters with an onboard system of EPL detection were based on identifying the electromagnetic emission from EPLs conveying a current. But such systems do not function if an EPL is not conveying a current. Moreover, the range of such systems depends on the dimensions of the receiving antenna and actually does not exceed a few hundred meters, and this by no means always gives the pilot a chance to perform an effective emergency maneuver.

The proposed complex operates on the principle that, irrespective of weather conditions, the effective temperature difference between the EPL and the surrounding atmosphere amounts to several degrees Kelvin even if the EPL is not conveying a current. This has made it possible to obtain information about EPLs by means of infrared detectors mounted on a gyroplatform; the received data are processed by digital methods in a special-purpose onboard computer.

The data are processed by means of original identification algorithms, which assure high-quality images of obstacles on the pilot's monitor at considerable distances from an EPL even in the event of natural interference.

One such algorithm is based on the premise that individual EPL segments can be interpreted as lengths of straight lines whose average brightness exceeds that of the background.

The image is scanned line by line by a specially tailored rectangular window, which consists of three bands of the same width: an upper, a central, and a lower band. If each band contains more than one line of pixels, it is replaced by a single line by the method of width averaging. The window formed in this way, in each of its positions, represents a certain region of the entire image.

The scanning is performed at different angles, corresponding to all the possible EPL directions.

Another algorithm is based on the heuristic method of median filtration, which uses learning programs and effectively suppresses graphic noise.

Experimental testing of the described algorithm showed that it can be used for the reliable detection of high voltage EPLs on IR. images at a distance of up to 1 km.

The figures, which are computer readouts, show EPLs on real backgrounds, obtained in the IR region of the spectrum (3-5 and 8-14 m m), before and after processing by means of the algorithms described above.

The cost of the proposed complex should not exceed $30,000 without the cost of the onboard gyrostabilized platform, which is part of the standard equipment of a helicopter. If the onboard equipment includes an IR camera, the cost of the complex should not exceed $ 2,000.

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