For my part time bachelor's in electronics we made an autonomous drone that could fly a preplanned pattern and recognize people through machine learning. Software: Ardupilot and ROS. Hardware:home made 3d printed drone,PX4, Nvidia Jetson, some Intel camera). Very fun and absolutely something you could tinker with as an hobbyist (it was basically a thesis on a hobbyist project).
We first tried with a raspberry pi based autopilot, it crashed and we rebuilt it again and again until we realized the GPS was broken.
Example code from the project for inspiration: https://github.com/bachelor-2020