The loco positioning system is designed to provide absolute positioning (and thus autonomous, accurate flight) using a series of active RF anchors/nodes. I do have one of these systems but I haven’t had the time to fully test it out yet. From what I’ve seen in Bitcraze’s marketing materials and demo videos, it looks very very cool. It’s quite pricey (The “explorer bundle” gets you the full system — A crazyflie 2.0, a crazyradioPA, and the loco positioning hardware — for $1000.00 USD) but if it works as promised, that’s cheaper than any comparable indoor localization scheme I’m aware of. I’ll be posting a follow up review on the Loco Positioning System once I’ve had sufficient time to really dig in and learn how it works and performs. For now, I just wanted to draw attention to the fact that it exists.

There are a few other localization decks that are related to positioning and autonomous flight: The Flow deck uses an optical flow sensor to estimate lateral movements from the air and a time of flight sensor to measure distance to the ground. The Z-ranger deck contains just the time of flight sensor to measure distance to the ground. Finally, Bitcraze has recently announced the Obstacle avoidance/SLAM deck adds time of flight sensors to the sides and top to aid with distance ranging in all directions.

I imagine a combination of the flow and SLAM deck would be great at achieving basic autonomy and localization of a single crazyflie in an enclosed space, but the Loco Positioning system would be great for absolute positioning (and relative positioning for managing a swarm of drones) indoors and outdoors.