The control harness, on the left, used for programming animatronic characters’ movements.
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Animatronics have powered some of sci-fi and fantasy cinema’s most imposing creatures and characters: The alien queen in Aliens, the Terminator in The Terminator, and Jaws of Jaws (the key to getting top billing in Hollywood: be a robot). Even beloved little E.T.—of E.T.: the Extra-Terrestrial—was a pile of aluminum, steel, and foam rubber capable of 150 robotic actions, including wrinkling its nose. But although animatronics is a treasured component of some of culture’s farthest-reaching movies, it originated in much more mundane circumstances. According to the Disney archives, it began with a bird.
Among the things Walt Disney was renowned for was bringing animatronics (or what he termed at the time Audio-Animatronics) to big stages at his company and elsewhere. But Disney didn’t discover or invent animatronics for entertainment use; rather, he found it in a store. In a video on Disney’s site, Disney archivist Dave Smith tells a story of how one day in the early 1950s, while out shopping in New Orleans antique shop, Disney took note of a tiny cage with a tinier mechanical bird, bobbing its tail and wings while tweeting tunelessly. He bought the trinket and brought it back to his studio, where his technicians took the bird apart to see how it worked.
Enlarge / The bird that reportedly started it all, bought by Walt Disney in New Orleans in the 50s.
This led to the Disney engineers experimenting with what eventually became Walt Disney’s Enchanted Tiki Room, a building full of animatronic birds signing, flowers blooming, and tiki drummers drumming. Disney was able to make the birds work years before computer programming, engineering, sound, and movement came together in a useful way.
According to an article from the defunct Persistence of Vision, Audio-Animatronics figures’ sounds were recorded onto tape, like a bird’s chirping. When the tape was played back, the sound would cause a metal reed in the system to vibrate. The reed’s vibration would close a circuit, allowing electricity to cross it and power a pneumatic valve in the figure to move (in the case of a bird, opening its mouth). When the sound stopped, the circuit would open again, and the bird’s mouth would return to its neutral, closed position. This way, the motion was dependent upon the sound, so the two would always operate together to create a realistic display of a singing bird.
The Enchanted Tiki Room opened in Disneyland in 1962, first as a restaurant and then as a standalone attraction. Throughout, the implementation remained simplistic. Disney was initially motivated to bring robots to life as a form of real-life animation, essentially taking movies off the screen and into three-dimensional space. But by the time the tiki room debuted, Disney’s team had been quietly pursuing a more ambitious goal—experimenting with more complex systems that could mimic human beings. They were getting close.
Toward a complicated human-robot
While the tiki room was being developed in the 50s, engineers at Disney were experimenting with "Project Little Man," an animatronic figure meant to mimic a Buddy Ebsen dance routine. While they made some progress, the figure was crude.
From there, Disney’s team experimented for a while with a Confucius-like animatronic character that was meant to stand in a restaurant entryway and serve pearls of wisdom when asked questions. That project fell by the wayside when Disney opted instead to work on an animatronic figure of President Abraham Lincoln, modeling its face on a real cast taken from Lincoln in 1860, the year before he took office.
For much larger figures like Lincoln, Disney’s technicians had to create system to control them that was more flexible. The digital system used for the Tiki Room birds above still worked for simple actions like blinking eyes or small finger movements, according to Persistence of Vision, but larger body movements required an analog system.
This was accomplished a couple of different ways, but both were based on a system of regulating voltage and triggering motion with tones. An increase or decrease in voltage was used to activate the more complex types of movement in animatronic figures, according to Persistence of Vision. For instance, if a figure’s neutral head position was hanging to the left, an increase in voltage would activate its hydraulics to make it start to move to the right. A decrease would swing it back to the left, and no voltage would return it to neutral. It’s easy to imagine how the on-off system described above for bird chirping would become alarmingly herky-jerky for, say, President Lincoln turning to look at you. To combat this, the voltage system allowed for smoother movements.
The animatronic president Lincoln standing to deliver his speech.
The voltage changes would be triggered by audio tones laid on 35mm film stock that signaled it to increase or decrease. The engineering team used a transducer that would relate the voltage changes to changes in sound, so that they could record movements and play them back.
Persistence of Vision states that a movement would be rehearsed, perfected, and then "recorded." An engineer would use a potentiometer joystick that applied and measured the voltage differences going to a particular joint. Once he had the motion down, he would perform the gesture by generating the ups and downs of voltage with the potentiometer, and the transducer would translate that to tones recorded on film. The engineers would then play back the track to see that the movement worked correctly.
This sounds simple enough for a single movement, but most animatronic figures’ acts were composed of many different motions coordinated together. For instance, just raising an arm to point one’s finger to emphasize something they were saying would require shoulder, elbow, wrist, and finger movements that all had to happen in tandem. Movements for each joint for each act would be recorded on one reel, and then all the movement reels would be combined into a master tape. Persistence of Vision notes that for the Carousel of Progress exhibit put on by Disney at the 1964 World’s Fair, four narrator figures had a combined 120 actions that were all recorded on one one-inch 32-track master tape.
The other solution also used voltage regulation, but it didn’t require a system of timed cues. Instead of working on one joint at a time with a transducer and potentiometer, engineers used a wearable control harness, visible in the Dave Smith video, that was hooked up to an animatronic figure. The harness measured voltage differences across its various joints and mimicked the changes in the animatronic figure connected to it, recording the movements to tape. The harness had the benefit of being able to record complex multi-joint movements, but it required perfect performances from the wearer, who had to sit for hours trying to get the motions right.
The animatronic Lincoln used both types of motion, though because of maintenance and space constraints, the actual materials used to execute the necessary motions were improved between the time Disney first started developing animatronics and when the figure debuted. For instance, the engineering team later started integrating servo valves, which can translate digital signals into smooth movements and would have cut down on the need for precise voltage difference recordings for some motions.
The animatronic Lincoln debuted at the 1964 World’s Fair as part of the state of Illinois’ pavilion. "He" could stand up from a chair and deliver snippets from the president’s most famous addresses. "Audiences were really amazed at this. They thought it was an actor up there that was standing on the stage," Smith said. Animatronics filled several other Disney exhibits at the fair, including "It’s a Small World" and the General Electric Carousel of Progress.
As animatronics circled back around from being an expression of live animation to a special effect in movies, the importance of programming and coordinating their performances perfectly fell by the wayside. While some programming still was and is necessary, the need for a full-on illusion is rarely necessary. But even if it’s no longer the standard it once was, Disney’s systems for its birds and its robot President laid the foundation for some of film’s most awesome displays.
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