[beshur]’s 2-year-old is obsessed with transportation, so he lifted a few DUPLO blocks from the bin and made this toy traffic light as a birthday present. Hey, might as well get him used to the realities of traffic, right? It also makes for a good early hacker lesson: why buy something when you can make it yourself?
The traffic pattern is determined by an Arduino Nano V3 situated inside the carved-out rear block. There’s a push button on the side in case there’s a spill and the lights need to go blinking red until the issue is dealt with. Instead of trying to solder everything in situ and risk melting the plastic, [beshur] dead-bugged the LEDs and resistors to the Nano with a helping hands and then worked everything into the case. The 5mm LEDs fit perfectly into the drilled-out posts of a second block and produce a nice, soft glow. Proceed with caution and check it out after the break.
Of course, plastic building blocks can do real work, too. This LEGO chocolate pantograph is pretty sweet.
Source: STOP ‘N GO DUPLO