The idea of using 3-D “printing” to perform rapid prototyping of many automotive parts has become a well-established technology to save time and money. But Local Motors, an ambitious startup that intends to build complete cars, demonstrated its technology at NAIAS, and showed a vehicle that it drove into its display area. The production system is called “BAAM,” for Big Area Additive Manufacturing, which is a description for 3-D manufacturing of big parts.
Cincinnati Inc., a maker of 3-D printers and the Department of Energy's Oak Ridge National Laboratory have an agreement to develop the equipment and processes for BAAM. Local Motors project is just one of the efforts in this area, and the first seeking to "print" a car.
Renault EV "city car" components
All right, the entire car can’t be printed of course, but a complete body and chassis can, and the Local show vehicle is equipped with Renault electric vehicle components (from the Twizy, a “city car,”) and described as a neighborhood EV with a top speed of 25 mph (40 kph). Until Local has gone through crash and other testing, and milling and other work, to produce a finished car that can be sold, it is in the proof-of-concept category. Renault is not a designated supplier for the electrical and mechanical componentry, and was used simply because of suitability and availability for the project, the company said.
The body-chassis, down to the cup holders, is made in layered sections, with specific toolpaths for each layer. The material is a carbon-fiber composite ABS that is most readily available in pellet form and much less expensive than the more common filament plastic that normally is used in 3-D printing. Local is experimenting with carbon-fiber concentrations ranging from 13% to 20%. SABIC, which is supplying the material, is a diversified producer of chemicals and such plastic materials as polyolefins, polyethylene, and polypropylene.
Every part of the car that is not mechanically or electrically involved is fused into a single piece. Seats and cushioning will be made in a Local Motors facility.
The demonstration vehicle that Local drove into the show display is far from a finished vehicle, as a look at the illustrations indicates. The layering look is crude, and although robotic milling and multi-color manufacturing may not be insurmountable challenges, they still have to become proved processes.
At this stage the viewer sees an assemblage of parts, with one major structure that needs much more precision in both the 3-D process and the finish milling. And taking what presently resembles a high school hand-built project car to a level that will command the necessary price for a business case may be a greater challenge than just "bigger and more" of the smaller parts for which 3-D production has been used for many years. So the road from proving the process to making salable vehicles may take longer to travel than the two years in the company's optimistic projections.
"Print" time is 44 hours
Local CEO Jay Rogers said that production time for the show vehicle, called the Strati (layer in Italian) is 44 hours, but his belief is that a complete vehicle can be built in a day. The company has a target price range of $18,000 to $30,000 for vehicles, with the appeal in the idea of customization, which he hopes would become primarily a matter of a software change.
The car was the achievement of an engineering community of 100,000 worldwide that the Local startup was able to assemble, with central validation by an in-house team in Chandler, AZ. Engineering contributors will be paid on a royalty basis according to the importance of their work, Rogers said. Local intends to set up micro-factories throughout the U.S., each with an estimated cost of $8-10 million for a production capacity of about 3000 units per year, from five or more 3-D printers and milling machines, which operate in series.
Initially, Rogers said, there will be one factory in Tennessee, close to the Oak Ridge National Laboratory. A second is planned for National Harbor in Maryland, a commercial development close to Washington, D.C. If the approach is successful, he said, he envisioned micro-factories in other countries as well.
The 3-D production concept lends itself to a wide variety of motor vehicles, from EVs to off-road to motorcycles. In an era of rapid improvements in computer-directed processes, Local Motors may merely be visionary, able to see its finished projects of the future. If it can go from the rudimentary look of its NAIAS show vehicle to something more akin to kit cars, it could find a waiting market. To its credit, Local Motors did not try to disguise its vehicle with hand-finishing, beyond the installation of the electrical and mechanical parts. It delivered an apparently honest "here is where we are now, but watch us" presentation.Continue reading »