BS2 and Odometer

rixter

Has anyone ever attached an odometer (cyclometer-coil/magnet pickup) feed to the BASIC Stamp? Perhaps this could be accomplished in some other way as well. Essentially what I am looking to do is have a sensor that monitors wheel revolutions and feeds this to the Stamp. I will then use code to calculate distance traveled knowing wheel circumference. It looks like a typical output from a cyclo-computer pickup is in millivolts, but I've not been able to measure this yet with equipment I have. The question is.... how can I turn a millivolt pulse into something I can use on the Stamp?

PJAllen

Get a Hall-Effect Switch (not to be confused with a Hall-Effect Sensor); when a magnet comes near them the output changes state, a "digital" (wither ON or·OFF)·output requiring no amplification, etc.

Update --
http://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?langId=-1&storeId=10001&catalogId=10001&productId=319100
Some switches turn on with one polarity and turn back off with the other polarity (requiring two magnets), but this one turns on in the presence of a magnetic field and turns off in its absence.

Post Edited (PJ Allen) : 2/11/2007 2:34:07 AM GMT

rixter

Thanks

I will look into the Hall Effect Switch for consideration. I imagine there are several ways to accomplish what I am trying to do. I started with the cycle computer sending unit because I am a cyclist and a spare old cycle computer was handy. The sending unit is generally fairly durable, taking abuse from water, road dirt and vibration.

I am not trying to re-invent the odometer but rather "enhance" it I guess you could say. I am building a specialized off-road enduro motorcycle racing computer that adds to what would be available on a typical computer for a bicycle. Functions will be based on time and distance traveled just as a regular odometer. The additional information I'll present will assist in keeping the rider "on time" in the event.