Walkers are vehicles from the Star Wars universe that traverse the landscape on mechanical legs. They are used by the Old Republic and the Galactic Empire for ground assault or transport.
There are a variety of walkers: Star Wars Episode V: The Empire Strikes Back introduces the All Terrain Armored Transport (AT-AT) and All Terrain Scout Transport (AT-ST), while Star Wars Episode II: Attack of the Clones, Star Wars Episode III: Revenge of the Sith, and the Star Wars Expanded Universe feature numerous others. Walker variants have been merchandised and featured in popular culture.
The AT-AT is a large, four-legged walker introduced in The Empire Strikes Back and also appearing in Return of the Jedi.
For The Empire Strikes Back, however, the final design was a four-legged walker. Industrial Light & Magic (ILM) created models ranging from 6 to 50 centimeters in height. ILM filmed the AT-ATs using stop-motion animation against matte paintings created by Mike Pangrazio because attempts at compositing miniature footage against live-action background footage yielded mediocre results. The sound of the AT-AT walking was created by Sound Designer Ben Burtt, by using the sound of an industrial sheet metal stamper.
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