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Circuit that controls time and distance for a 7.6v vehicle?

  1. Oct 1, 2015 #1
    I have to design a circuit that can control how long it takes for it to travel a given distance. I do not have much progress. I am wondering what type of circuit this is?
  2. jcsd
  3. Oct 1, 2015 #2


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    Staff: Mentor

    Cruise control?
  4. Oct 1, 2015 #3
    Last edited: Oct 1, 2015
  5. Nov 4, 2015 #4
    Since the 555 is rated to work with a Vcc from 3 to 15V, the circuit should work as designed at 7.6V.

    However, I am not quite sure how your problem is defined. The circuit you showed is a pulse-width modulated speed controller (aka chopper circuit). It will control the speed of the motor, which is one way to control "how long it takes for it to travel a given distance." But the motor will keep travelling at that speed forever.

    Your second post implies that you want to stop the motor after a given duration, which is a different approach to the problem.

    The 555 timer on the ebay product will be configured as an astable multivibrator, with the on-board pot controlling the duty cycle. A duration controller would use a 555 configured as a monostable multivibrator. The circuits are not very different, and a bit of cutting and soldering could probably turn one into the other. Without seeing the schematic, it is hard to tell how practical this would be.

    You might use two of these in series: a monostable circuit to control the duration followed by an astable to control the speed.
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