China’s Alibaba says that it has built the world’s first self-driving vehicle guided by solid-state lidar. The vehicle’s a truck; the lidar comes from China’s Robosense.
That’s one small step for delivery bots, but one giant leap for solid-state lidar.
A small step, because delivery bots are already out there, managing without lidar. A giant leap, because solid-state lidar has so far been mostly just a smile and a shoeshine. The one production car to sport lidar—the upcoming 2019 Audi A8—packs a mechanical form of the device and uses it only for traffic-jam assist and other functions below true self-driving.
Today’s delivery bots are mostly cutie-pie small and bound largely to the sidewalk, like Piaggo Fast Forward’s Gita and Starship Technologies’ eponymous machine. And the one big, road-going one, Tesla’s planned truck, has no lidar and is no more capable of driving itself than any other Tesla.
Alibaba’s G Plus vehicle is billed as a road-going truck that indeed will drive itself—someday—thanks in part to its three lidar sets, two fore and one aft. Such a truck would sure fill a need—in the United States, for instance, there’s a massive shortage of truck drivers. But how close that dream is to realization is almost irrelevant here. Everybody’s making airy self-driving claims nowadays.
What really matters is that Alibaba is embracing a solid-state lidar rather than the big, burly, and costly mechanical alternatives put out by Velodyne, the market leader (and, any day now, by upstate Luminar).
Robosense’s lidar instead uses microelectromechanical systems (MEMS) mirrors to steer the beam.
“RS-LiDAR-M1Pre MEMS micro mirror scanning scheme requires only a few laser emitters and receivers to scan the MEMS micro-mirror in both directions because of the swing angle,” Robosense says in a release. “Resolution is a very fine, high and vertical angle resolution of 0.2° throughout angle of view.”
Exactly how fine that resolution is the release does not say. The company’s website lists various models, one apparently providing 32 beams, another only 16. Velodyne’s top-of-the-line mechanical scanner offers 128.
There’s also a trade-off between spatial resolution and the number of frames a system can scan in a second. Lidar can either scan fast for a few pixels or slowly for a lot more; combining high resolution with a fast frame rate requires muscle—more muscle than any previous solid-state system has yet been able to muster.
Philip E. Ross became a senior editor at IEEE Spectrum in June 2006. His interests include transportation, energy storage, artificial intelligence, natural-language processing, and the economic aspects of technology. He has reported on solar towers in Spain, cloud seeding in Nevada, telescopes atop a mountain in the Canaries, and robotic cars in California and Germany. He blogs mainly for Cars That Think, which won a 2015 Neal Award. Earlier in his career he worked for Red Herring, Forbes, Scientific American, and The New York Times. He has a master's degree in international affairs from Columbia University and another, in journalism, from the University of Michigan.