Just wanted to give a shout-out to the guys who played the robots

The robots were great and the actors did a hell of a job playing them.

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http://en.wikipedia.org/wiki/Silent_running#Production

The three drones were played by four bilateral amputees, an idea inspired by Johnny Eck, a sideshow performer of the early 20th century who had been born without lower limbs. The 20-pound (9-kg) drone suits were custom-tailored for the different actors. The suits are in Douglas Trumbull's personal collection.

Mark Persons ... Drone 2 - Huey
Steven Brown ... Drone
Cheryl Sparks ... Drone 1 - Dewey
Larry Whisenhunt ... Drone

http://en.wikipedia.org/wiki/File:Making_of_Silent_Running_Drone.jpg
With its cover-plate removed during a shooting break, double-amputee actor Mark Persons is visible inside the tiny Drone 1 (Dewey) costume
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