When Chevrolet set out to refresh the Malibu’s interior and exterior
for 2014, designers used one of the most cost-effective and time-saving
methods in its high-tech tool box: rapid prototyping, also known as 3-D
printing.
The processes literally grow prototype parts out of powder or liquid
resin at a fraction of the cost associated with building tools to make
test parts. Selective laser sintering and stereo lithography – the
official names of the processes – helped accelerate Malibu’s development
and evaluation. Both processes use specialized software, math data and
digital lasers, which accomplish in days what would have taken weeks of
clay sculpting in the past.
Rapid prototyping enables designers and engineers to quickly see,
touch and test versions of individual components and systems in precise
one-third scale and full-size models without having to make changes to
production tooling, which can cost hundreds of thousands of dollars.
“When you need to get intricate, fully functional prototype parts
quickly, nothing beats rapid prototyping,” said Todd Pawlik, chief
engineer, Chevrolet mid- and full-size cars. “Our ability to rapidly
fabricate inexpensive prototype parts throughout a vehicle enables key
components to get confirmed earlier so that we can go from computer
models to production-caliber parts.”
Rapid prototyping proved particularly useful for updates to the new
Malibu’s floor console, which now features a pair of integrated
smartphone holders for driver and passenger. The new console also weighs
less, which helps contribute to the Malibu’s improved fuel economy.
In addition, the Malibu development team used rapid prototyping to:
- Update the center stack trim and evaluate various surface treatments for the console and center stack
- Create a prototype of Malibu’s redesigned front fascia, enabling
aerodynamic and climatic wind tunnel testing without expensive
production parts.
- Re-sculpt the front seat back panels – located between seat frame
and upholstery – for improved rear seat access and passenger comfort.
The 2014 model has 1.25 inches more knee room compared to its
predecessor.
Here’s how rapid prototyping works:
Selective laser sintering fuses plastic, metal, ceramic or glass
powders in cross sections. A laser scans a pattern on the surface of the
powder, fusing the particles together into a layer four-thousandths of
an inch thick. As each new layer of powder is added, scanned and fused
to the previous one, the part gradually takes shape within the
28-inch-cubed reservoir.
Stereo lithography combines photochemistry and laser technology to
build parts from liquid photopolymer resins. The parts are also built up
in layers as a UV laser traces the section onto the surface of the
resin, curing the liquid into a solid as it scans. Because the resin
won’t support the parts being formed, a fine lattice-like structure is
generated below each part during the manufacturing process.
*Courtesy of GM News
