Society of Robots - Robot Forum
Mechanics and Construction => Mechanics and Construction => Topic started by: I-Jeff-I on December 24, 2009, 07:16:53 PM
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Hi I have a quick question. I just hooked a DC motor up to an L293D H-bridge so that two buttons spin the motor in one direction or the other. Sometimes though, I need to spin the motor a little bit to get it started. When I press the button it twitches, but doesn't start moving. Other times, it works fine, usually after it is already spinning. Is this normal? Is there an easy fix to this?
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Hmm, do you know what the stall current of the motor is? It might be that the h-bridge cant supply the motor with enough juice to start it but it has enough to spin it...
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this is the motor:
http://www.radioshack.com/product/index.jsp?productId=2102828 (http://www.radioshack.com/product/index.jsp?productId=2102828)
and this is the h-bridge:
http://www.st.com/stonline/products/literature/ds/1330/l293d.pdf (http://www.st.com/stonline/products/literature/ds/1330/l293d.pdf)
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Well, the page doesn't say what any of the info apart from voltage is :-\
The H-bridge can supply 600mA and 1200mA at peak...
Unless we can get a ballpark figure of the motors current draw this will be a hard one to figure out.
Have you tried putting one motor on both of the channels to double output current?
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wow that worked, thanks a lot. I guess I should have checked out the specs first :/ thanks again!
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Anytime :)