The artists militarized a basic walking machine concept by giving it an armored body and guns,and designed a head that could turn as if seeking prey, an effect that lent animal characteristics to the walking tank. It was felt that the snow walker would be a much more awesome weapon if it were made to seem animallike, designed by the imperial forces to terrify the enemy.
The walker interior was designed around the idea of two pilots and possibly one officer working inside the cockpit. A tight-fitting room, the cockpit would also house various controls and other hardware items needed to operate the compicated tank. Two operators were required to handle the two main lasers, two side guns , visions in the front, and the foer walking legs.
Except for the set pieces needed for extreme closeups of the walker'S underside and cockpit interriors, no full size construction was necessary. An eighteen-inch model of the machine - meant to appear fifty feet tall in the film - was built and used in stop-motion animation.
The model was set up on a miniature snowspace and shot a frame at a time as the legs were moved by very small increments between frames. The walker's mechanical nature made it an ideal subject for stop-motion work, as this sort of animation gives an unavoidable strobing effect. This effect lends a mechanical appearance to animal puppets, but only served to to enhance the menacing movement the filmmakers wanted to achieve.
In devising movements for the walker miniatures, animators Jon Berg and Phil Tippet studied the movements of a variety of animals. But the walkers's unique mechanism and design dictated its own movements.
AT-AT schematic
Pre-Walker tank idea for imperial snow troops.
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Snow Walker Cockpit
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Early sketch of "Turtleshell" walker body.
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Early Walker body and head.
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Sketch with snowtrooper and snowspeeder to show walkers scale.
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