NASA Gives The World a Brake
Just as NASA needs to reduce mass on a spacecraft so it can escape Earth’s gravity, automotive manufacturers work to reduce weight to improve vehicle performance. In the case of brake rotors, lighter is better for a vehicle’s acceleration, reliable stopping, and even gas mileage. Orbis Brakes Inc. licensed a NASA-patented technology to accomplish that and more. This revolutionary brake disc design is at least 42% lighter than conventional cast iron rotors, with performance comparable to carbon-ceramic brakes.
Jonathan Lee, structural materials engineer at NASA’s Marshall Space Flight Center in Huntsville, Alabama, uses his skills as a mechanical designer backed with material science training on multiple projects including the Space Launch System and the International Space Station. Interested in supporting NASA’s other mission to advance technology to improve life on Earth, he was looking for an innovative way to design a better automobile disc brake.
He started with a single disc with a series of small fins around the central hub. As they spin, these draw in air and push it across the surface of the disc, where the brake pads make contact. This cools the rotor, as well as the brake pads and calipers. He then added several long, curved depressions around the braking surfaces, radiating from the center to create the regular, periodic pattern that gives the new technology, known as Orbis, its PeriodicWave brand name.
The spinning fins and the centrifugal force of the wheel push air into trenches, causing a turbulent airflow that draws away heat. These trenches in the braking surfaces also increase the available surface for air cooling by more than 30% and further reduce the weight of the disc. They also increase friction in the same way that scoring concrete makes steps safer to walk on – the brake pads are less likely to slip, which makes braking more reliable.
The troughs draw away more than just heat, too. Water and road debris getting between the pad and rotor are equally problematic, so the grooves provide a place for the air vortex to push any substance out of the way. A small hole machined at the end of each one creates an opening through which unwanted material can escape.
The expertise developed while solving problems in space has proven useful on Earth, too. Orbis’s brakes are sold as aftermarket modifications for high performance cars like the Ford Mustang, as well as some Tesla models.