A few ideas: have computer vision tool analyze each frame from one or more cameras above the field, look for the drones, and overlay your graphics. You might h

A few ideas: have computer vision tool analyze each frame from one or more cameras above the field, look for the drones, and overlay your graphics. You might have a QR Code or similar. Even a simple color badge if it's just a handful of drones. Then, your cv code just has to look for the big chunk of pink, blue, or green pixels. Look up color tracking, object tracking, etc. Look into https://en.wikipedia.org/wiki/FoxTrax https://en.wikipedia.org/wiki/FoxTrax as an old example. OpenCV, Tensorflow possibly as tools now. As you noted in another comment, GPS by itself probably isn't accurate enough, but there is GPS augmentation tech. You put a base station in the area that measures the drift and sends that over the air to use as correction. I'm thinking you'd take the raw GPS from the drones, apply the correction, and hopefully get sub-meter positioning. Look up DGPS, WAAS for options there. The other idea that comes to mind is to triangulate based on their radios. You'd have base stations around the perimeter, each measuring the signal strength and direction of the target frequencies. Positioning would be a matter of fairly simple trig + error correction. I don't know if there's anything doing this off-the-shelf, but indoor positioning systems may be a rabbit hole to go down (even if used outdoors). A final idea is to use the video feed from the drones. You'd place QR Codes throughout the course, process the video feeds, and use the codes seen in each feed to tell which ones are ahead. Or instead of QR Codes, build a point cloud of each point on the course to use as position. Sounds fun!