Abstract:
Pakistan is hit by some natural disasters in last ten years including 4 major floods and 1 the biggest earthquake of the history of Pakistan claiming millions of precious lives. Government sector as well as non-government organizations spend heavily for the immediate rescue and relief operation. Government helicopters are used for the surveillance and rescue purposes to identify the ravaged areas and to locate and save lives holding breath. The immediate rescue and relief operation can be multiplied by dividing the operation time and expenditure. The aim here is to develop unmanned helicopters indigenously, which can provide a very cheap and low cost solution for the initial disaster surveying and later on, for small scale relief package drops. Out of about nine systems required to be developed for such a program, in this work a video system, sensor system, and ground control station has been developed. In this long range vision system for an unmanned helicopter, the on board telemetry information data is overlaid on a video stream and is then transmitted at 2.4 GHz frequency from 10 kilometer line of site distance. After receiving and amplifying the video signal, the telemetry data is then extracted and used as a real time visual feedback to control and maneuver the unmanned helicopter through communication system when it goes beyond the visual range. The developed vision system has been successfully tested at 14 kilometer line of site distance. Despite the efficiency, with every meter increase in the wireless link length, there are losses due to absorption, scattering, reflection and diffraction which attenuate the signal power and results in the degradation of the video quality. Nevertheless this system is a low cost, small size, light weight and above all, power efficient full fledge vision system that is portable and can be installed in any ready to fly unmanned air vehicle with as low pay load capacity as 3.0 kg.
