Hey everyone! I am working on an electric go kart project and have been doing extensive research into motor controllers. I would like to interface a motor controller like this (http://www.monsterscooterparts.com/36-volt-1000-watt-controller-electric.html) with my Arduino. Normally one of these controllers would take the input of a throttle potentiometer like this (http://www.monsterscooterparts.com/thswasformia.html), however, I would first like to input the potentiometer value into my Arduino (no problem there!) and then pass it back to the motor controller. However, I know that the value outputted by PWM pins is 0-256, and the value of the potentiometer will be different. How can I "emulate" the value of the potentiometer to the motor controller?
What about getting the Arduino to control a digital potentiometer. Then there is no need for any change to the controller.
If you only want the Arduino to know the potentiometer setting (and not to control the speed) perhaps you could just tap into the existing circuit to measure the voltage on the pot.
...R
Replace the pot with a fixed resistor (they usually specify 5k or 10k), leaving the wiper connection free to
drive from a low-pass-filtered PWM signal.
But first check the voltages the unit is using with a real pot in position. Needs to be in 0..5V range.
Most controllers detect open or short circuit in the control pot so you have to provide a real resistor
to avoid triggering error-shutdown.