4 Mar
2010
4 Mar
'10
8:37 a.m.
Jonathan Gazeley:
...
I want to measure how fast I'm turning the pedals
on my bike (the
"cadence") and synthesize/sample the sound of an internal combustion engine.
...
Sounds
like fun.
1. A sensor that can measure my cadence. A simple
magnet switch that
triggers once a revolution won't be enough to measure the cadence with
sufficient resolution, since my cadence is usually between 50 and 80
rpm. I would probably need to mount multiple magnets spaced equally
around the chainwheel and have a single sensor on the frame. Then I have
to get it to supply this information to my control program.
...
Why don't you put an inductive sensor [1] at the pedal gear teeth?
You could probably mount it at the chain protective cover if the
tolerances are the right. Have a look at Omron "E2E-X5MF1 2M" [2,3]
(you might have to paint it to protect it from water). For that one
you need 12-24V DC.
Regards,
/Karl
[1] http://en.wikipedia.org/wiki/Inductive_sensor
[2] http://www.ia.omron.com/product/family/449/index_fea.html
[3] http://www.ia.omron.com/product/item/e2e_7258d/index.html
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Lilla Aspö 148 Networks
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