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[on:]

Hi everybody,

i'm sensing the speed of a wheel (bike) with a Dynamo (DC motor) and then i send the data to the serial port, the problem that i have is that the Dynamo(DC motor) is sending a lot of noise and because of that i can't get the correct data of speed.

there is a way with hardware and software to supress that noise?

[Reply #1 on:]

... is a way with hardware and software to supress that noise?

Yes, it is.
Best you start plotting the signal so we can have a look at the different situations, and explain how you tried to determine the velocity from that signal at the moment.

[Reply #2 on:]

You might try some capacitors like below.

http://www.pololu.com/docs/0J15/9

[Reply #3 on:]

But a dynamo should produce AC not DC...

Looks like another " Guess and fail" game  

[Reply #4 on:]

But a dynamo should produce AC not DC

Maybe this is a language thing - in English, a dynamo is specifically a DC generator.

[Reply #5 on:]

Bicycle generators are commonly called dynamos (at least in blighty) despite them almost universally producing AC. Its a misnomer, just like central heating calorifiers are almost universally called 'boilers' despite them most definitely not being boilers.


Driving incandescent lamps it makes little difference if they are AC or DC.

[Reply #6 on:]

Problem solved, thanks..

i was a little confuse of the voltage of the dynamo, and it was AC,, so i did a rectifier bridge and a filter, so now works perfectly

[Reply #7 on:]

Maybe this is a language thing - in English, a dynamo is specifically a DC generator

Most foreigners - I think - are not aware of this. In the German language the term Dynamo is nearly exclusively used for the thing at bicycles.

In a more technical slang Dynamo would actually describe an AC generator, in contrast to Gleichstrommaschine which is explicitely DC (=Gleichstrom). In English it is vice versa: 'dynamo' is DC and 'alternator' is AC...

The term 'generator' is - in both languages - used unspecifically.