I have developed some environmental allergies over the past few years and now if I don’t take a daily allergy pill, I feel pretty miserable. Now that it is Spring, I need that daily pill but I keep forgetting whether I took it. Sometimes in the evening, sometimes in the morning… it’s all to sporadic to remember. So I remembered seeing this Every Day Calendar here and decided I needed a more compact (and less expensive) version of this to put inside my vanity cabinet. Besides, the Every Day Calendar Kickstarter has closed and they are in their production phase.
I dove pretty far down this rabbit hole designing a one-month calendar that would have basically the same functionality but only give you 31 days, a selectable month indicator (Jan, Feb, Mar, etc.) and have multiple users (so both my wife and I could share it.) Without remembering that this thread existed, I also decided that neopixels under the keys would be a more versatility design (for various reasons like coding missed days as "red’ or different users could use different color schemes, or just show random colorful effects, etc.) Using neopixels also simplifies the design since I don’t have to use GPIO expanders or LED driver ICs; all I have to do is string 48 neopixels together and supply power and ground to each. (I think that the current day LED should “breathe”, like the Particle device status LED, reminding you that you need to complete the task and then end up solid/steady once pressed.)
I designed the bottom “controller” board with 48 capacitive touch inputs (and headers for attaching to a separate touch plate PCB), 48 neopixels (one under each key), six 8-channel capacitive touch controller ICs (I2C bus comms), three 2-channel I2C multiplexers and headers for an Argon (or any mesh device).
Now I am moving on to the touch plate PCB with the capacitive touch pads and I’m realizing that designing the touch pads is a major design hurdle! I am trying to do the same type of design as in the Every Day Calendar (solid pad with character cutouts) because letting the LED light shine through the PCB is a major design attraction/feature. I’m using Eagle and making a copper pad with a cutout is painful. I even tried making the pad design in Inkscape and saving it as a .dxf file for import to Eagle (using this tutorial). The import works, but the pad becomes an outline using wires rather than a solid, filled polygon. I know this isn’t an Eagle forum, but does anyone have advanced PCB design experience that can suggest the best method to make the below image a solid polygon without having to manually trace the outline using the polygon tool?
The .dxf designed in Inkscape (black should be solid copper, the numbers should be bare PCB without any soldermask, copper, silkscreen, etc.):
The pad after importing the .dxf into Eagle: