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How Animatronics Works


Big as Life
Once the sketches and models are done, the full-size building begins.

Build a Full-size Sculpture
For the animatronic dinosaurs in the original "Jurassic Park," SWS had to build the full-size sculpture by hand, a time-consuming and laborious process. Advances in computer-aided manufacturing (CAM) allow them to automate a significant part of this step.

The maquette is taken to Cyber F/X, where it is scanned by a 3-D digitizer. This is nothing like a normal computer scanner. There are a variety of methods used in 3-D digitizers, but the one that was used for Spinosaurus is called laser scanning.

Laser scanning takes precise measurements of the maquette by bouncing beams of laser light off its surface. As the laser scanner moves around the maquette, it sends over 15,000 beams per second. The reflected light from the beams is picked up by high-resolution cameras positioned on either side of the laser. These cameras create an image of the slice (cross section) of the object that the laser is scanning. A custom computer system collects the cross sections and combines them to create a perfect, seamless computer model of the maquette.


Photo courtesy Stan Winston Studio, photographer Chuck Zlotnick
Details are carved into the full-size sculpture.

Cyber F/X then used the computer model to mill the life-size model of the Spinosaurus from polyurethane foam. This very rigid foam is cut to the correct shape through a proprietary process called CNC-Sculpting®. This process, developed by Cyber F/X, takes the data from the full-scale computer model and divides the model into manageable chunks. The data for each chunk is then sent to the foam-sculpting machine, where a life-size section of the dinosaur is created by whittling away pieces of foam from a large, solid block using tiny spinning blades. Once all the sections are done, the SWS team assembles the pieces like a giant 3-D jigsaw puzzle. This creates a very basic full-sized model. A lot of work still needs to be done and it is handled by a team of sculptors at Stan Winston Studio. They hand-carve the foam to add all the incredible details that make it seem real.

Molding and Casting
A set of molds are made of the full-sized sculpture. The molds are made from an epoxy that is very durable and has strong bonding characteristics.


Photo courtesy Stan Winston Studio, photographer Chuck Zlotnick
Creating the mold

Once the components of the animatronic device are ready, much of the frame work is test fitted inside the molds before the foam rubber skin is cast. In conjunction with this step is the fabrication of the foam-running core, which is created by lining the inside of the mold with precise layers of clay to represent the skin thickness. When the clay lay-up is completed, the surface of the clay is fiberglassed to create the foam-running core. After the clay is cleaned out, the foam-running core is bolted into the mold and creates a negative space between the foam-running core and detailed surface of the mold. When filled with foam rubber, this negative space becomes the skin.

The purpose of this process is twofold:

  • It makes the skin movement seem more natural
  • It controls the skin's thickness and weight

Let's move on to the building of the animatronic components.