This tool is designed to help train beginners to electronics and robotics get comfortable with how Pulse Width Modulation works.
A small box with a screen, RGB LED and 3 dials. It can also have a power switch, and mode button.
Power wise, some sort of USB power. It doesn't need to be battery operated.
The main mode:
- Each dial controls the PWM duty cycle for the R, G and B channels of the LEDs
- The screen shows either the ratio percentage, or a square wave for each channel.
- The LED will be showing the appropriate colour.
Alternative mode
- Control one LED colour
- Dial 1 controls the PWM frequency down to 1 Hz
- Dial 2 controls the PWM duty cycle
- Screen displays the values along with a rendering of the square wave
Potentially have test points for 3 PWM signals, and a ground point exposed.
Use the microviews in my storage, this might be enough for the display. It might need a larger screen, but start here. The microview is basically an Arduino plus display.
I have some pleasing potentiometers with a linear dial, which I can use for the 3 controls. Use an RGB LED that takes 3 power inputs along with resistors, not a smart LED - that way, an oscilloscope probe would show the same waveform.
Design a board (strip board/perf board/protoboard) layout for this - which will also likely mount the potentiometers. Design a 3D printed case which accounts for the user elements, power/programming cable and test points.
It should probably be prototyped with less fancy potentiometers on a breadboard first, so we can chekc viability of the display on the Microview.
Design this for reproducibility
- Electronics design should be KiCAD.
- Layout/Case design in FreeCAD
- Code using Arduino IDE/Toolchain
Store STLs, board layout PDF's in this repository, along with code and guides both on building and using this tool.