Please help out a frustrated person.
I cannot for the life of me figure out how to control the resistance of a circuit using arduino.
The parts I need to control are...
- Electric Power Steering
- Power Steering Controller (off the shelf) that controls the errr.. power steering
The process is as follows currently. Both parts are controlled via standard car power (say 12v for simplicity sake). The Control Box has a potentiometer on it that allows the driver to adjust the amount of assist that the steering column offers. Dead easy. At speed, you'd want the power steering less active and at low speeds (for example parking) you adjust the resistance of the pot to make the steering really light.
That's all great, except I don't want a pot in the equation that I have to adjust manually. I can read the speed off the vehicle using an output of my ignition controller. So we have an input signal.
What is really frying my brain is how to control the amount of resistance across two points in the circuit.