John Gardner wrote:
> It's possible to measure power with accelerometers.

Not for very long, and certainly not in any practical way for a bicycle tri=
p
logger.

>  VELOCITY=3DMPH x 5280/3600

Actually MPH (miles/hour) already is velocity.  There is no need to multipl=
y
it by a dimensionless quantity.  If you wanted velocity in different units,
like feet/second for example, then you would be multiplying numbers with
units and specify the units velocity is in.  That's not what you did, so
your equation is rather pointless, or misleading at best.

>  FORCE=3DMASS x (ACCEL+DECEL)     ;  ACCEL & DECEL in < g >

Yes, as per Sir Isaac.

>  HP=3DFORCE x VELOCITY/550

More disregard for units.

In addition, your equations have two major problems.  First you assume mass
is known.  That's possible but not all that practical.  The worst problem
however is that deriving velocity is highly error prone.  If you had shown
the calculation of velocity from the accelleration you might have seen this=
..

Velocity is proportional to the integral of accelleration.  This immediatel=
y
brings up two problems.  First, the starting condition needs to be known.
You could make the rider provide a indication of stopped or maybe detect
overall lack of vibration and assume that implies stopped.  However, by far
the worst problem is that any accelleration error will accumulate over time
into velocity.  Any affordable accellerometer will produce unusably wrong
velocity within only a few seconds of reset.

What you are proposing is essentially inertial navigation.  Look up that
term to see why that's a completely unworkable idea in this context.


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