An Ex-Marine Wants to Print Autonomous Vehicles for Your City

On an isolated stretch of industrial flatland outside Knoxville, Tenn., a minibus is taking shape in a car factory unlike any other. The space is small, the size of a supermarket, and all but tool-free. No pneumatic pumps, no shuttling parts bins, no robotic arms or conveyor belts carrying skeletons of cars. Instead, perched in the center is the world’s largest 3D printer, a gangly 10-by-40-foot behemoth with a steel-gray exterior, thick columnar footings, and derrick-like roof beams to true its frame.

When the print heads are in motion, the equipment emits little more than a whisper, dexterously cutting sharp angles and rounded edges. Programmers on laptops and quality-control experts with tablets mill around, inputting design changes and fine-tuning the minibus’s sensor instructions. Beyond the assembly room lies a kind of alchemist’s playground, where young staffers with advanced degrees in materials science and mechanical engineering synthesize nanopolymers or test exotic particles for strength or thermal and electrical conductivity.