Object tracking and detection for short range surveillance using 2D ultrasonic sensor array

Ultrasonic motion sensors consist of transmitters that emit ultrasonic sound pulses into the monitored area, which would return immediately when it encounters obstacles on the way and a receiver acknowledges the return of the signal. Transmitted sound uses air as medium. Distance measurement is done with respect to the time delay between transmission and reception. This system is based on many such detectors that are arranged in an efficient manner, the outputs of these various sensors are used to determine and decide the movement of the object. The aim of this paper is to realize the design of a sensor array which can detect motion in any environment or medium and also be economically viable and portable. The system is aimed at short range but accurate detection. The system can also be used to trigger external circuitry that can perform certain tasks without human intervention which makes it ideal for use in remote security systems. The sound used are pulses of 40khz frequency and hence cannot be detected by the human ear, making the system undetectable. The system is useful in environments with moving objects, without which the system continues to scan for moving objects indefinitely till said object is found. This system will be achieved with very little computational power which makes this ideal for many situations. The system after design and construction was found to work as per the conceptual idea.