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Electronics => Electronics => Topic started by: jorj on August 12, 2009, 07:19:19 PM

Title: search the easier solution to control a motor
Post by: jorj on August 12, 2009, 07:19:19 PM
I need a motor that rotate in 60 degree right and when the motor terminate the 60 degree right the motor rotate 60 degree left and continue this loop until I turn off the motor
I don't want to do an electrical circuit and to compute
I search after the easier solution
Title: Re: search the easier solution to control a motor
Post by: billhowl on August 12, 2009, 07:37:37 PM
May be you can try car windscreen wipers motor
http://en.wikipedia.org/wiki/Windscreen_wiper (http://en.wikipedia.org/wiki/Windscreen_wiper)
Title: Re: search the easier solution to control a motor
Post by: wil.hamilton on August 12, 2009, 07:46:57 PM
uh, or you just use a servo?  that's what they're built to do
Title: Re: search the easier solution to control a motor
Post by: jorj on August 12, 2009, 07:58:57 PM
Thanks billhowl & wil.hamilton
Wil.hamilton I think that I don't understand you
maybe You can explain me
Title: Re: search the easier solution to control a motor
Post by: SmAsH on August 13, 2009, 12:27:58 AM
a servo:
(http://www.acroname.com/robotics/parts/R276-S03N-SERVO.jpg)
with the right code will do that, here is some arduino code to "sweep" the servo from left to right.
Code: [Select]
void loop()
{
  for(pos = 0; pos < 180; pos += 1)  // goes from 0 degrees to 180 degrees
  {                                  // in steps of 1 degree
    myservo.write(pos);              // tell servo to go to position in variable 'pos'
    delay(15);                       // waits 15ms for the servo to reach the position
  }
  for(pos = 180; pos>=1; pos-=1)     // goes from 180 degrees to 0 degrees
  {                               
    myservo.write(pos);              // tell servo to go to position in variable 'pos'
    delay(15);                       // waits 15ms for the servo to reach the position
  }
}
this will sweep the servo from 0 degrees to 180 degrees then back again...
this could easily be made to do 60 degree sweeps.
Title: Re: search the easier solution to control a motor
Post by: Soeren on August 13, 2009, 12:53:26 AM
Hi,

a servo:

Quote
I don't want to do an electrical circuit and to compute

Allways read the original post, then you don't generate annoying space waste for others to scroll through ;)
Title: Re: search the easier solution to control a motor
Post by: wil.hamilton on August 13, 2009, 09:12:13 AM
@soren
i more think he didn't want to the calculation of of a control circuit for using a dc motor

what smash gave him is one of the easiest things he could do

another option is using the GM10 (http://www.pololu.com/catalog/product/195) which has a mechanical stop at 60 deg both directions
so you would just have to turn the motor on one way and then the other
Title: Re: search the easier solution to control a motor
Post by: blackbeard on August 13, 2009, 10:33:56 AM
jori i mean this in the best way but you're a bit hard to understand. if English is your second language maybe an online translator might be a bit easier. as for limiting the range of motion i'd like to know more about what it's used for. if it's small enough you could just add physical blocks to alter the range of motion.
Title: Re: search the easier solution to control a motor
Post by: Soeren on August 13, 2009, 03:14:39 PM
Oh, come on guys. billhowl read the post and nailed the solution IMO.
What the OP asks for is a continous back-and-forth motion of 60°.
A DC motor with a linkage akin to a wiper motor, scaled to whatever size needed IS the simplest solution - wax on/wax off nothing more to it :)
Title: Re: search the easier solution to control a motor
Post by: wil.hamilton on August 13, 2009, 08:21:14 PM
building something like a wiper assembly would probably be too complex to build in the size he would need it.

anyway, here is how wipers work: http://auto.howstuffworks.com/wiper1.htm
Title: Re: search the easier solution to control a motor
Post by: billhowl on August 13, 2009, 10:13:14 PM
(http://www.scary-terry.com/wipmtr/comparisons.jpg)
This is the wiper motor that I talk about, all in one assembly.
You just need to buy the motor and use it.

Here are some project page.
http://www.scary-terry.com/wipmtr/wipmtr.htm (http://www.scary-terry.com/wipmtr/wipmtr.htm)