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Speed up a stepper motor

Discussion in 'Robotics & Mechatronics' started by mesamune80, Jul 14, 2006.

  1. mesamune80

    mesamune80 New Member

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    which mean to say that,it is independent on the driver is it?no matter how good your driver is, it still cannot exceed the torque limit of the motor?
     
  2. phalanx

    phalanx Member

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    There is no hard "torque limit" in an electric motor. You can likely exceed the rated current of the motor and produce torque higher than what is listed in the datasheet. You will begin to get diminshing returns due to field saturation in the magnets. Keep increasing the current and you could eventually damage the magnets.

    Torque is related to the current flowing through the windings of the motor. More current = more field. More field = more torque.
     
  3. hjames

    hjames New Member

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    Physical limits are hard to bypass... I point out steppers in particular because they are pretty darned reliant on magnetics. As far as I know, if you disassemble any stepper motor and pull the rotor (with magnets) out of the housing, that'll damage the magnets. If you want more info, search for "stepper demagnetization".

    This person has a useful picture of torque vs speed vs current for some stepper - notice that torque drops off pretty quickly versus speed - regardless of the current. I think this is pretty typical for steppers.

    http://www.krupin.net/serendipity/i...-motor-driver-why-I-needed-my-own-design.html
     
  4. dave

    Dave New Member

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  5. mesamune80

    mesamune80 New Member

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    now i think of want to drive the bipolar motor and i think i can no longer use this UCN5804B to drive them,as mention by phalanx and james the A3984 and A3977 both are DMOS microstepping Driver with translator,But can i know how to hook this to my microcontroller so that i can easily drive them?Thanks.
     
  6. phalanx

    phalanx Member

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    Just read the data sheets. All the motor controllers made by Allegro Microsystems are pretty easy to interface with.
     
  7. mesamune80

    mesamune80 New Member

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    Ok,i'll read through the datasheet very carefully,hope the interfacing is simpler than this UCN5804B ,one of the reason i feel it is harder is because the number of pin it goes there =.="
     
  8. yazid

    yazid New Member

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    u use assembly language for the coding or c language?i already done to make the various speed of the stepper motor by using assembly language.but now..i want to change the code to c languange...
     
  9. watzmann

    watzmann New Member

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