What topic should I subscribe to know when the drone is in "hover state"?
Basically, I'm trying to write a piece of code that waits for the drone to enter hover state and then take a picture from the drone's camera. I've manage to take the picture (by subscribing to ardrone/image_raw topic). I only need to know what topic should I subscribe so I can set up a subscriber and using a callback function I will be able to take pictures from the drone only when it is in hovering state.
Thank you in advance.
p.s: I use tum_ardrone and ardrone_autonomy to communicate with the drone. I've also created a package that uses some opencv code to take the picture from the drone's camera.