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Electronics => Electronics => Topic started by: carlos067 on January 06, 2010, 01:58:02 PM

Title: anolog control of motor position?
Post by: carlos067 on January 06, 2010, 01:58:02 PM

Hey guys I have a quick question. I am building a sensor that is constantly moving. It will receive a 0-5V signal of wind direction from an anemometer and would like a stepper motor to recognize the 0-5V signal as a 0-359deg position command. I was thinking of using an analog to frequency converter, but wouldn't that just take the instantaneous volage and output a certain number of pulses meaning a turn of a certain amount? I would like to keep the sensing part always facing the wind.

Thanks in advance,
Carlos

Title: Re: anolog control of motor position?
Post by: Soeren on January 06, 2010, 03:24:37 PM

Hi,

Just make it like the ones used on weather stations, they're allways facing the wind.
Another method, if position sensing isn't needed, is to use a heated platinum wire.

Title: Re: anolog control of motor position?
Post by: carlos067 on January 06, 2010, 04:03:28 PM

Thanks for the idea, but I would like to log direction data, either way I think I found a way to do it. IMS has stepper motor controllers that have an analog input, I could then use Mcode to write a program read the analog input scale it and have the motor do what I want.

Title: Re: anolog control of motor position?
Post by: Soeren on January 07, 2010, 05:48:15 PM

Quote from: carlos067 on January 06, 2010, 04:03:28 PM

Thanks for the idea, but I would like to log direction data,

The oldfashioned 3 half cups anemometer will work from any horizontal direction and a weather vane will allway point the way the wind is coming from, so in combination with an absolute rotary decoder (can be made on a PC and LASER-printed on a piece of overhead film, to be read by IR forks) and it will allways give you more precise data than if you try to follow the wind with a stepper.