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IIIA.2
04-01-2010, 03:12 AM
Hi, I'm taking robotics as an elective and i think you may categorize me as a 'beginner.' Well, right now my class is dealing with the motor's RPM. Thus, my question is, how can I speculate the RPM of the continuous rotation servo when it is assigned a particular motor speed???

Here is the code sample the teacher handed to me;

' {$STAMP BS2}
' {$PBASIC 2.5}
loopcount var Word
motor_speed var word
loopcount = 150
motor_speed = 1200

DEBUG "Motor On", CR
DO WHILE loopcount <150
Pulsout 13, motor_speed
PAUSE 20
Loopcount = loopcount + 1
LOOP

DEBUG "All done."
END

Thanks :)

erco
04-01-2010, 04:09 AM
Empirical observation, Watson! It's all approximate, and will vary based on your particular your setup, servo, load & battery voltage. With fresh batteries, test several different pulsouts and count revolutions per minute and make a lookup chart. It will be roughly repeatable, but RPM will slow down as your load increases or your batteries poop out. For more consistent results, use rechargeable batteries, NiMH or LiPo.

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"If you build it, they will come."

IIIA.2
04-01-2010, 05:20 AM
Thank you. :)

silverback
04-01-2010, 07:20 AM
IIIA.2 said...
Hi, I'm taking robotics as an elective and i think you may categorize me as a 'beginner.' Well, right now my class is dealing with the motor's RPM. Thus, my question is, how can I speculate the RPM of the continuous rotation servo when it is assigned a particular motor speed???

Here is the code sample the teacher handed to me;

' {$STAMP BS2}
' {$PBASIC 2.5}
loopcount var Word
motor_speed var word
loopcount = 150
motor_speed = 1200

DEBUG "Motor On", CR
DO WHILE loopcount <150
Pulsout 13, motor_speed
PAUSE 20
Loopcount = loopcount + 1
LOOP

DEBUG "All done."
END

Thanks :)
If you are using a parallax CRServo your pulsout range is 650 to 850


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If you convince yourself that something is impossible before you even try; you are sure to prove yourself right.

Franklin
04-01-2010, 10:50 PM
Also the motor won't rotate because of the value of loopcount.

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- Stephen

Spiral_72
04-01-2010, 11:14 PM
Franklin said...
Also the motor won't rotate because of the value of loopcount.


HA! you're right! So to answer your question..... RPM = 0

http://forums.parallax.com/images/smilies/lol.gif

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"puff"...... crap, there went another one.