idea for Neo 2nd generation: Accelerometer

David Ford david at
Fri Jan 26 19:40:41 CET 2007

Tim Newsom wrote:
> Ok Steve.  I grant you that the first derivative of acceleration is
> velocity... How do you propose to gain any velocity information when
> the acceleration measured is zero as would be the case if you are at a
> constant velocity?  This is why I am saying you would need some better
> source for velocity.
>  I grant you that the times when a car is at a constant velocity may
> be few... Or it may be that when on cruise control on any flat road
> you may actually see zero or almost zero acceleration.
> OTOH, detecting the direction that a person turned with the
> accelerometer may be very useful in dead reckoning.
> --Tim 


The acceleration to 50 kilometers per hour then staying at that speed
produced an acceleration vector in a given direction.  Until there are
mathematically equal opposing deceleration(s), you have a known velocity
and vector.

It's all in the math :)  Zero acceleration only means your current
velocity and vector are constant.


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