Long story short, 3 years ago I gave a shot to the build of a sonic screwdriver board, as I got solicited for this several times and found it would be a good challenge to see how small I could make a sound board with extended electronics, including a motion sensor, and proposing some additional interaction features:
As a result, in 2017, I managed to cram a motion sensor, 2W audio amp, microcontroller and several led outputs into 24.5x10 mm, all this on a PCB that I could still assemble at home with my Pick and Place.
My buddy Eastern57 also made a large variety of sonics (or sonic inspired props) that are really worth checking out
After I made 2 runs of those, I moved to a V2 version with a digital sensor and implemented some of the suggestions I got:
I started by installing a RGB LED in the front nozzle after removing the stock electronic board. I used a common cathode RGB LED since my board powers from 3.3V led outputs. The board has footprints for installing 0603 SMD resistors (they will come with the board). They aren't installed since there's no per-required color mapping for the led channels. The RGB led (5mm) is exactly the same size as the stock LED which combines visible LED + IR (TV remote)
No crazy mods in the sonic body to fit the electronics. The stock board was attached to the negative (spring) of the battery so I made a small PCB out of perfboard to keep this and glued it in place, preserving the spring-loaded mechanism that connects the 2 sonic halves (twist-lock).
From there I only had to snip a few plastic tabs to free up some room for the replacement board
Sonic reassembled, you can spot the blue auxiliary led that mixes up with the green one, in extended/unlocked mode
Power supply side, I'm using a single 10440 cell (protected), 3.7V nominal (AAA sized). Since the sonic body has room for 2xAAA, I machined a dummy AAA with my lathe and a PVC rod, drilled it in 3mm to install a M3 threaded rod that slightly sticks out of the dummy battery body to make the positive. The negative is a M3 (screwed in the threaded rod) nut offering a larger butt surface like a regular battery.
♦ Extension sensor (magnetic) demo, while being installed
♦ And final demo (alternate sound package)
|1 x||Color Xtender Dual Ch. Current Regulator for HB leds|
|1 x||The Mad Map A3 Print|
|1 x||Pico Crumble™ V2.5 DARK|