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3-D Scanner For Films
David Armstrong

A hand-held scanner invented by a group of Christchurch scientists is being used by the film industry in New Zealand and the United States for computer-based animation.

The laser scanner and associated software can reconstruct in a few seconds a digital 3-D image of any irregularly shaped object, arranging the data in formats ready for use in popular computer-aided design and animation software packages.

After three years of development backed by government-agency grants, Applied Research Associates has begun reaping some rewards as its US-based distributor, Polhemus, this year has sold the high-tech product to some of the leading players in the film industry.

One FastScan unit is being used by Peter Jackson's Weta Productions in Wellington to help animate the Lord of the Rings movie.

ARA was formed in 1995 by Rick Fright, Mark Nixon, Brent Price, and Bruce McCallum to develop the hand-held scanner from Dr Fright's earlier ideas and work at Christchurch Hospital.

Various fixed-geometry laser and X-ray scanners are available for medical and industrial applications, including radiotherapy treatment planning and skull-damage repair. All are limited by their inflexible mechanisms, and are expensive.

ARA's portable FastScan unit uses a planar laser beam shining on the object, with reflections recorded by two cameras on the scanner arm. This allows data to be recorded for irregular and hard-to-get-at shapes, such as the nose.

Several scans may be recorded around the object, each taking no more than a few seconds. The software quickly merges the overlapping data into a three-dimensional mesh, ready for design work.

What makes ARA's device unique is its ability to work from flexible angles, rather than a fixed-geometry framework. This is achieved by a magnetic tracker nearby, which emits a set of magnetic pulses to provide reference data for the position and orientation of the scanner wand.

The scanner, which sells for $US30,000, is a vital tool for film and advertisement animators. It can track 3-D shapes as they move around, providing graphic designers with a frame of reference on which to hang their creations.

Another application is rapid prototyping of objects to be manufactured. A clay model of an object such as an ergonomically-shaped mouse, can be scanned, and the resulting data used to drive a computer-controlled milling machine.

The scanner can also be used to design cosmetically attractive prosthetics and orthotics, such as to repair a jaw or skull.

ARA will remain primarily a research rather than production firm, funded from research grants and product licensing and royalties, says a director Mark Nixon. It has six full-time and several part-time staff, with half its revenue coming from a share of sales by Polhemus, currently running at about three units a month.