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Digital engine

  1. May 14, 2010 #1
    i read that motors can be operated by interfacing them with micoprocessors(stepper motor),so can this be done with modern day engines?
     
  2. jcsd
  3. May 14, 2010 #2

    FlexGunship

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  4. May 14, 2010 #3

    FlexGunship

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    Okay... let me try here:

    You have read that motors can be operated by interfacing them with a "mico" processor called "Stepper motor."

    Motors are controlled by different methods:
    • PWM DC
    • DC current modulation
    • AC current modulation
    • AC voltage modulation

    Their shaft positions are reported by feedback devices:
    • optical encoder
    • sin/cos incremental encoder
    • magnetic pole position resolvers

    By using a setpoint driven system and comparing that setpoint to feedback device's location (called error) to feed a controller (usually a PID controller), you can maintain reasonable control over the motor.

    As for a stepper motor: they are just a special kind of synchronous motor. Nothing really different here, except that they are usually designed for small discrete movements. Stepper motors are often multi-phase internally, but might still be fed from a DC source for simplicity.

    Can you control a stepper motor based on feedback using modern drive equipment? Yes, absolutely. There's a good chance that if you have a late model car, the gauges on the dash are actually connected to stepper motors.

    Then you mentioned something about "modern day engines."

    When I think of an engine, I think of an ICE (internal combustion engine). However, obviously this isn't what you meant since ICEs aren't controlled by magnetic field generation using electric current, they are controlled by explosions in cylinders generating a linear motion that is converted to rotary motion by means of a crankshaft.

    So, I have no idea what you meant with that last comment.

    As a side note, though... internal combustion engines have been using computers (micoprocessors?) to help control fuel mixture (by means of fuel injection systems) and timing (by means of relative spark advance and retarding systems). Lots of new engines also use variable valve lift accomplished by non-linear camshaft geometry.

    Lastly, perhaps you are talking about the electric "engine" in a Prius, or other hybrid cars. This is just an electric motor. There is no electric "engine" to speak off. Rather there is an internal combustion engine and an electric motor on a shared-shaft power delivery system. Is there a computer in a Prius? Definitely!

    Now... please... what question did you intend to ask? I can't guess anymore.
     
  5. May 14, 2010 #4
    Maybe he meant John Galt's electrostatic motor.
     
  6. May 14, 2010 #5

    FlexGunship

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    Who is John Galt?
     
  7. May 14, 2010 #6
    Touche
     
  8. May 16, 2010 #7

    MATLABdude

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  9. May 18, 2010 #8
    i meant ECUs only,now that is interfacing right.
     
  10. May 18, 2010 #9

    FlexGunship

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    [PLAIN]http://www.donself.com/images/confused-baby.bmp [Broken]

    This is either a misuse of the word "interfacing" or a weird sleight-of-hand trick you are performing with the English language.

    Yes, you can use a microprocessor to model a control loop for operation of a stepper motor through an "interface." Yes, modern vehicles use software to control the air/fuel mixture in the cylinder of the engine through an "interface."

    But a vehicle's ECU has more software in common with a fruit-juice mixing computer than with a motion control processor.
     
    Last edited by a moderator: May 4, 2017
  11. May 19, 2010 #10

    MATLABdude

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    Unfortunately, I don't know if there's a language barrier, but I and FlexGunShip aren't understanding your question. Are you asking if there's a way to interface with an ECU to change things like fuel mix, throttle, and the likes? BTW, a more detailed description of what an ECU is:
    http://auto.howstuffworks.com/under-the-hood/trends-innovations/car-computer1.htm

    If so, maybe: it depends on the ECU and the make of the car (as you probably read in the Wikipedia article I linked to)--probably in conjunction with some sort of OBD-II (On-Board Diagnostics) interface unit, for instance:
    http://www.scantool.ca/ [Broken]

    Most you can read from, some you can reprogram / control (or replace with one which you can). I understand this is popular in certain racing/modding circles:
    http://www.hondatuningmagazine.com/tech/0506_ht_ecu_tuning/index.html
     
    Last edited by a moderator: May 4, 2017
  12. May 19, 2010 #11

    FlexGunship

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    Ugh... did you just quote a Honda site as reference to "racing/modding circles"?

    I call: Forum Foul. Red flag. 5 minutes in the penalty box.

    2010-04-09%2010.54.31.jpg

    That image is from my car. You'll see the little mini-computer (with "micoprocessor") on the right side of the dash. That's a tuning device. It interfaces to the OBD2 port and allows for piggyback control, over-writing of the ECU, tuning of the fuel curves, and realtime data acquisition.

    To quote the OP: "now that is interfacing, right?"

    fonzie.jpg
     
    Last edited: May 19, 2010
  13. May 19, 2010 #12

    MATLABdude

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    My idea of car mod:
    [PLAIN]http://www.lubengomn.com/lubengomn/images/P8180036.jpg [Broken]

    (Okay, maybe a little higher, but only up to the point of taking apart panels, and installing lights and what not...)
     
    Last edited by a moderator: May 4, 2017
  14. May 19, 2010 #13

    FlexGunship

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    SPOILER ALERT
    http://www.igelior.de/pictures/co/spoiler.jpg
     
  15. May 21, 2010 #14
    thanks.i got it.
     
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