Society of Robots - Robot Forum
Electronics => Electronics => Topic started by: benji on September 26, 2008, 05:09:14 AM
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I was thinkin to build/design a circuit to optimally control dc motors
i mean
1/ speed
2/ position
3/torque
4/ brake << most important
anyways the most used way to control speed is PWMing the dc motor so the average voltage would change
but,, is this efficient enough ? wouldnt be more efficeient if we decrease the supply voltage?
i was thinking if a group of us share the design , we can build it together,, wut do u think?
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you are trying to make continuous rotation or not?
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both ,,
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anyways the most used way to control speed is PWMing the dc motor so the average voltage would change
but,, is this efficient enough ? wouldnt be more efficeient if we decrease the supply voltage?
i was thinking if a group of us share the design , we can build it together,, wut do u think?
A PWM motor drive is very efficient. A PWM motor drive effectively decreases / increases the supply voltage to the motor by vary the PWM duty cycle. There are many, many designs out there already and even chips that implement those designs.
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well i was talking about the 4 things i want to control,, im thinking an individual speed/torue/position driver
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Oh. OK. That does sound like a good project.
There is a commercial version:
http://www.pololu.com/catalog/product/425 (http://www.pololu.com/catalog/product/425)
but I haven't seen many hobbyist-designed solutions.
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I was thinkin to build/design a circuit to optimally control dc motors
i mean
1/ speed
2/ position
3/torque
4/ brake << most important
anyways the most used way to control speed is PWMing the dc motor so the average voltage would change
but,, is this efficient enough ? wouldnt be more efficeient if we decrease the supply voltage?
i was thinking if a group of us share the design , we can build it together,, wut do u think?
Have you seen my Motor Driver tutorial at http://www.societyofrobots.com/member_tutorials/node/159 (http://www.societyofrobots.com/member_tutorials/node/159)
This helps set speed etc and the Tri-State Switch also provides braking.
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hey webbot ,,good work ,,ihave seen some ICs ,they could be helpfull
they can be included in such a circuit i guess,,
but im talking about somthing bigger,,, maybe close to industrial inverters for ac motors
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well first , considering such a project one should model the dc motor,, have the equivalent circuit
i ve been lookin for it and most sites on the internet tell that its (R ,L ,emf) the emf is propotional to the rotational velocity
any other components to include?
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now i know where to start , first to model then to build the controller, im gonna use matlab for modeling/controller PID design
i found this link very benefical and it has some other links mentioned below in the page
www.engin.umich.edu/group/ctm/examples/motor/motor.html (http://www.engin.umich.edu/group/ctm/examples/motor/motor.html)