Hey guys, I am a software developer by trade and I'm trying to earn my hardware hacking merit badge
Please talk to me like I'm totally ignorant.
The last electronics project I did was building a TV transmitter from a kit with my dad (and I helped!), and that was years ago.
I am attempting to connect an Arduino to a 2.4GHz R/C controller for a sick co-axial helicopter I have. It is important to note that this helicopter features a 4 channel controller (Throttle, Yaw, Pitch, Roll). I cracked this baby open and (no big surprise) found 4 potentiometers. I grabbed my volt meter and played around with each. From testing the middle (wiper?) pin I was able to determine that the voltage to these pots ranges from 0 to 4v. Using analogRead with the Arduino I am able to detect the position of the joysticks and their potentiometers pretty reliably.
However, I would now like to supply power from the Arduino to each pot and bypass the sticks to allow controlling the Heli from the Arduino. I tapped in to the middle pin on the throttle and things work semi-ok using analogWrite; However the rotors have a kind of pulsing effect I am curious if this is due to the PWM. I have also run in to another issue where the right joystick has springs on it that keep it centered. This means that the pot sits at about 2v, if I send 4v from the Arduino, wouldn't that total 6v and cause problems? I am thinking I might need to short-circuit the pot's positive pin to the pot's ground pin, but that feels dirty. Ideally any modifications I make to the transmitter would not prevent it from working in the future. So far all I have done is tapped in to the wiper pins on the pot and run wires outside the transmitter.
My Questions (TL;DR)
- Is the effect of the PWM noticeable when using analogWrite as a potentiometer?
- Is there an easy way to short circuit a pot and reset it's voltage to 0?