Have you ever wanted a London underground train door button in your house?
When I saw these on the LTM site I knew I had to make something from them. I was surprised how easy the conversation with Mrs. MartinelliMakes was when I told her I wanted to cut a hole in the downstairs loo wall.
As with most projects it's an ESP32 sandwiched behind there with a serial interface to control an Adafruit Audio Fx board.
the code is pretty simple and selects one of 7 tube related sound bites when you press the button and flashed the lights just like the real door. You can cancel a a playing sound clip by holding the button down
Interesting technical note:
The unit was totally sealed with no physical contacts exposed on the case. It's inductively coupled to the train car and doesn't appear that it would ever actually perform the function of opening the door.
Instead I think it's just a placebo giving the passenger something to jab, or at lest it would if there weren't trackside barriers at all Jubilee line stations to prevent you from ever pressing these buttons. Probably explains why they were removed as part of the rollingstock refresh.
Most stuff starts out with a prototype on breadboard unless I'm really sure what I'm doing.
I didn't take many photos of the assembly phase or hole cutting as I got a bit carried away.
The ESP32 powering this is on an Over-The-Air setup so I can push new code to it without having to dig around in the wall with a USB cable.