The MEMS mirror at the center of the circuit board provides the scanning function in the 3D imaging lidar. (NASA/W. Hrybyk)

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 will generate real-time images needed to guide the vehicle to a target traveling at thousands of miles per hour. A team at NASA’s Goddard Space Flight Center is developing a next-generation 3D scanning lidar — dubbed the Goddard Reconfiguable Solid-state Scanning Lidar (GRSSLi) — that could provide the imagery needed to execute these orbital dances.

GRSSLi is a small, low-cost, low-weight platform capable of centimeter-level resolution over a range of distances, from meters to kilometers. Equipped with a low-power, eye-safe laser; a MEMS scanner; and a single photodetector, GRSSLi will "paint" a scene with the scanning laser, and its detector will sense the reflected light to create a high-resolution 3D image at kilometer distances.

A non-scanning version of GRSSLi would be ideal for close approaches to asteroids. It would employ a flash lidar, which doesn’t paint a scene with a mechanical scanner, but rather illuminates the target with a single pulse of laser light — much like a camera flash.