Building, fixing, and refueling space-based assets or rendezvousing with a comet or asteroid will require a robotic vehicle and a super-precise, high-resolution 3D imaging lidar that generates the real-time images needed to guide the vehicle to a target traveling at thousands of miles per hour.

A team of technologists at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, is developing a next-generation 3D scanning lidar — dubbed the Goddard Reconfigurable Solid-state Scanning Lidar (GRSSLi) — that could provide the imagery required to execute these orbital dances.

Equipped with a low-power, eye-safe laser, a micro-electro-mechanical scanner, and a single photodetector, GRSSLi will "paint" a scene with the scanning laser. Its detector will sense the reflected light to create a high-resolution 3-D image at kilometer distances — a significant increase in capability over current imaging lidars that are effective only at meter distances.

Just as important, the instrument is equipped with onboard "vision" algorithms that interpret the three-dimensional image returned by the lidar. The softwar estimates location and attitude of a target relative to the lidar.

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Also: Learn about NASA's Asteroid Redirect Mission.