[Flightgear-devel] OT: real world tilt sensor

[Martin S. <ma...@pl...>]

Hello toghether,
maybe one of you has some experience on this topic.
I need a tilt sensor for a real world experimental plane project. An easy
way to build this is using two accelerometers to measure earth gravity.
One of these points down 45 degrees to the nose of the plane and one points
45 degrees to the back.

If both show the same acceleration (1 g * (1/sqrt 2)) then my plane is
parallel to the surface. If the one pointing towards the nose increases and
the other decreases to the same amount, my plane has the nose down. That is
proven to work. There's just one obstacle that prevents this configuration
to work in a real environment: When the whole plane accelereates, then I
also get an agle different to horizontal plane because the configuration is
sensing the acceleration even when the pitch is still the same.

If I had the money to buy a ready-to-go "Intertial Measurement Unit", then I
would not ask. But for a plane whose first prototype is in model plane size,
this would exceed the existing budget.

Does anyone know how this is done in a real plane ? I don't believe the
virtual horizon is showing strange pitch when the plane is acceleration on
the runway  :-)

Thanks,
	Martin.
-- 
 Unix _IS_ user friendly - it's just selective about who its friends are !
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