I have a question about using a RTK gps system for a quadricopter project.
I hope i'm in the right category for that.
We have to precisely position the drone (3m +/- 10cm) around a wing of a
windturbine for taking high quality pictures.
We have mounted a rotating lidar (RPLidar A2) on our Erle Copter to get a
position feedback on the pitch and roll axis, that we run through a P controller
to send velocity commands to ArduCopter. The commands are sent in Python through
DroneKit using MAV_FRAME_BODY_OFFSET_NED messages.
The problem is that, while this system works well in our Gazebo simulation, in
the physical world the drone is having an erratic behaviour, with wide random
movements. Enough for it to get out of range of the sensor or crash into the
Our current assumption is that the regular GPS that we are using along with
ArduCoper's EKF is not precise enough to position the drone around the wind
We have thought so far of two possible solutions: the first one, that we like
less, would be to use the GUIDED_NoGPS mode to send angle commands, develop our
own PID in python and infer the current speed from the Lidar measurement. A lot
of additional dev, uncertainity and no way to simulate this as the GUIDED_NoGPS
mode is not implemented in the Ardupilot version that we are using in Gazebo.
The other solution that we have thought of would be to use a RTK gps to get more
precision. This is why we would like some advice before spending 600+€ on it.
So, what do you think ? Is it likely that the cause of our problem is the
precision of the GPS ? Do you think that using a RTK would solve our problem ?
Would it even work for altitude instead of using a vertical rangefinder ? Have
you already faced a similar situation, and if yes how have you solved it ? Or
could you point us to somebody / somewhere we might get help from ?
Thanks in advance for your help.