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A fictional futuristic weapon that first appeared in the Aliens science fiction and horror film from the 80s.
The M56 Smartgun is a self-targeting heavy machine gun attached to a harness that is used as a squad support weapon by the Colonial Marine Corps.
An optical sensor in the gun detects moving targets previously programmed as such in a computer stored in the chest armor of the operator. Then when the target is in front of the weapon the suspension arm self adjusts to lock on the objective.
The smartgun is a very effective weapon for attacking upcoming hordes of fast enemies of any kind.
The user receives visual data from a headset connected to the targeting computer. It is equipped with a HUD display that shows the targeted treats and an alarm that informs the operator when a target is acquired.
It has two modes of operation: tracking and non-tracking fire. The smartgun uses caseless, high penetration armor piercing and explosive rounds. It's a formidable weapon that has two main disadvantages: Its size and heavy weight which reduce mobility and its rapidly depleting ammunition when not used properly.
In real life the M56 was designed by Stan Winston and James Cameron in the mid eighties, by using components from a steady cam harness, a WWII era German mg42 machine gun and several motorcycle parts.