Dead reckoning

[Jippieee]

Tom, I got the impression that a GPS device is currently mandatory for flight stabilization. Recently I read something about dead reckoning navigation. Would this also be possible with the gluon pilot for flight stabilization and simple navigation with the take off position as base? I am asking because some basic navigation seems just fine for simple flight patterns.

[Tom]

The GPS device is needed because we need to know the speed of our airplane. This is needed to calculate the centripetal accelerations (which are needed for stabilization: 20km/h or 90km/h is a big difference when making a turn). When no GPS device is installed (or better: when no valid GPS signal is found... no GPS unit at all would need a small fix), the speed is assumed to be the "cruising speed", which is configurable.

Dead reckoning is mostly useful in cars because the motion is simpler (2D) and they know the exact speed (turnrate of the wheels). For planes it is probably only useful when you fly simple routes at a constant speed (or if you have very expensive and accurate sensors).

For flights such as for quadrocopters (accelerations are really short, and it usually doesn't fly circles at high speeds), a GPS unit isn't needed.
For navigation (flying from point A to B) or flying at a speed higher then 10 or 20km/h and making large turns, a GPS unit will be required.