The unique techniques of life casting have found favor in many other fields such as prototype tooling, prosthetics, taxidermy, architectural restoration and special effects for film and television. The advanced technology used in animatronics also incorporates life casting techniques in the initial stages of creating the characters.
Animatronics refers to making and using robotic devices to imitate a living being. The creatures could be humans, animals (like dinosaurs and sharks), plant life or even mythical creatures. Animatronics brings lifelike characteristics to the inanimate objects so that they can walk, talk and do other activities in a natural way. The movements could be mechanized or controlled by computers.
Animatronics is largely used in films (20,000 Leagues Under The Sea, Jaws, E.T., Jurassic Park, etc), television and advertizing. This differs from computer animation as the simulated creatures are actually physically present and moving in front of the camera. The characters in various amusement parks also wow visitors with the aid of animatronics.
Making the creatures
Animatronics uses puppets, models and other figures which are then animated to emulate lifelike movements. The character first takes shape as a sketch on paper and scale models are created for approval.
Once approved, an internal supporting frame is carefully built using steel or even wood at times. Once the desired shape is achieved, electronic and mechanical components are attached around the framework.
The figure is finally covered with body shells that give it the shape and look of a real creature. Flexible skin is attached to the exterior of the figure that completes the lifelike appearance.
The skin can be made of silicone, foam latex or urethane. First a mold is made by using alginate or clay. The mold should be in the exact shape and size of the animatronics figure. Molds can be made in parts to allow for more ease of use.
The body mold is reinforced using plaster bandages to form a shell mold. Once cured, it is carefully demolded and will have captured the minute details which will be replicated in the skin cast. An alginate mold should be used quickly as it tends to shrink. The silicone or latex is poured into the mold and allowed to cure. Once fully cured, the thin skin cast can be easily demolded as alginate does not stick to anything.
The cast will have a texture similar to that of real skin. It will be flexible as well to allow facial and body movements as required. The demolded skin is cleaned and finished before being carefully attached to the figure.
The animatronics figure gets the final finishing touches in the form of eyes, teeth, hair, feathers and other such realistic characteristics. The requisite color pigments may be added to the skin during casting itself. Else, special silicone/latex paints are used to color the figure as required.
The figure is ready then be animated as desired.
The author is an experienced professional in the field of mold making. He has penned the article down to highlight the use of alginate in mold making.