I build 3d models using Agisoft and need to record the position of the Ground Control Points as accurately as possible, latitude , longitude and altitude. What is the best way of doing this?
The most accurate position is probably calculated by using a sensor-fusion algorithm.
As sensors you can use:
- GPS for absolute (but relatively inprecise position)
- Distance sensors (either via triangulation with multiple ground stations or via a SLAM algorithm)
- Odometric data from your quadrocopter (motor power)
- Acceleration (lot's of drift over time but precise for a short time)
This sensor data can be fused used something like a Kalman-Filter.