The modern United States Colonial Marine (U.S.C.M) motion tracker is a simple surveillance device originally designed for use by rescue and police services. Essentially, it is a high-powered ultra-sound scanner that Uses Doppler-shift discrimination to filter out moving objects from the stationary background. A moving object is shown on the trackers display as a series of contours of probable loci, with the range and bearing given to the target.
The Device was specialy built for James Camerons 1986 movie ALIENS.
Model Video: http://www.youtube.com/watch?v=eOWYykflVWQ&feature=youtu.be #Alien #Aliens #Colonial_Marine #Motion_Tracker #USMC