"It's those Vermont winters that provided motivation for the project. "If I am walking my kid to the bus stop in December and January, I would really rather not be doing that," Wallich told NBC News.
The drone is a quadcopter that he built from store-bought parts. He strapped on a smartphone with a video-chat app so that he could watch his son from the comfort of his warm home.
The trick was to get the drone to follow his son. After exploring a few possibilities, Wallich put a GPS beacon in his son's backpack, and employed navigation software that tells the drone to stay an arbitrary distance from the beacon.
It worked ... up to a point.
"Vermont, as it turns out, is a really bad place for doing this kind of thing because you have hills and you have trees," Wallich said. "Hills mean that the altitude control gets a lot more complicated and trees mean you have to do obstacle avoidance.
"If my kid is walking along the road and there is a branch overhanging the road, the quadcopter will gleefully run smack into it."
There are potential fixes, such as sonar for collision control. By flying the quadcopter closer to his son — about 15 feet off the ground — he could program it to maintain altitude with respect to the ground instead of following GPS coordinates."
Drone photo by Paul Wallich, via NBC News