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Author Topic: Sensing voltage from the power wires of an RC motor  (Read 728 times)
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Hi.. I'd like to try and rig up an arduino to control the speed of an RC car. I plan to use the cars built-in hardware for the radio communication and then sense the output sent to the motors using the Arduino. The arduino will then use it's own circuity to actually control the motor. (Yes, there's probably a more elegant way to do it  smiley-grin.. but I want to try this method)

The problem is in the fact that the output to the RC motor can change polarity to drive the motor in either direction. How will I be able to sense voltages which switch polarity with the arduino?
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If the Arduino is controlling the motor in the first place then why you need to sense what you feed it? You should know!

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I want to control the car wirelessly.. i.e Using it's remote.
I'm using the cars circuit to receive the radio signals and output then to the arduino.
The arduino will then used PWM to accelerate the motor gradually, instead of accelerating in one quick jerk. To to this, the arduino has to sense when the remote is sending the appropriate signals.
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You could use a logarithmic equation instead smiley-wink
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To calculate a value for the power sent to the motor?
...Well, yes. But I need the arduino to sense when the remote sends a signal to the cars' circuit so that it knows when to start the motor. 
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No, to gradually accelerate.
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I don't think you connected the grounds, Dave.
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Quote
the problem is in the fact that the output to the RC motor can change polarity to drive the motor in either direction.
So sense the input.
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No, to gradually accelerate.

yup, that's what I meant..

Ok, I'll try this out and post back.. any further posts would be useless, otherwise.
Now I need to get my hands on 6 AA batteries.. hehehe
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