I am starting a new project that uses the parallax model 750-90002 outrunner RC motor and a Turnigy electronic speed controller (ESC).
I have Turnigy model AE-20A ESC's and have been trying to figure out how to go about controlling it from the propeller chip.
I noticed the ESC I am using is also a very similar model to what is being used for the Elev8 project.
My project is a type of spinning clock. There is a 'blade' attached to the motor which I will be lighting up with LED's. I need the RPM to be constant or a way to trigger the LED's when in correct physical position for a steady image.
I have not connected or programmed the ESC yet... I would like to get more familiar before attempting anything as this will be my first time using an ESC.
First question... connecting to propeller for programming.
The connection from the ESC that would normally go to a radio receiver is 3-pin... I am assuming the white wire is for data, so connect the white wire to any desired prop pin?
Would connecting the red/black wire to the prop's 3.3v power be fine? Or is it a different voltage?
The ESC main power (where batteries would normally be used) will be a 12v switching power supply.
For programming the ESC, the instruction manual looks like it only uses 2 or maybe 3 input values (up, down, middle)... i.e. to start programming, hold throttle in 'up' position and power on the ESC, wait for tones.
So for programming the ESC from the prop, I was thinking of using 2 buttons on different prop pins to set the output of the ESC data wire at 'throttle up' position and 'throttle down' position.
So if I press button 1, the pin connected to the ESC data wire is set with outa~~ to simulate a 'throttle up' position.
If I press button 2, the pin connected to the ESC data wire is set with outa~ to simulate a 'throttle down' position.
Will this work? or should I use DUTY instead of outa? or does it work off of current sensing and so I should use a potentiometer?
This is more an extension of question2... for use after programming, how to go about controlling the speed of the motor connected to the ESC.
What kind of input does the ESC use for controlling the speed of the attached motor? Would I use DUTY on the ESC data wire for controlling the speed and simulating the throttle of an RC controller?
I am not sure yet of my desired RPM, but it will need to remain constant after finding an optimal speed.
I am worried about the project flipping on its side during startup while trying to go from 0 to set RPM due to torque, so I will need to ramp the starts.
I appreciate any help, I am worried about damaging electronics by using a trial and error process to figure this stuff out.
I see quadcopters are a hot topic right now! Hoping after this project to use the gained knowledge in building of my own :)