My son is a mechanical engineer in the city. He needed some help with software (that's my field), so he showed up with an Arduino microcontroller, some sensors, and a hacked Romotive robot base:

I was coding and uploading the programs, he was designing and 3d printing the necessary parts (he brought his printer too). We took over the dining room table for a few days (we had to eat in the living room):

Here's an early-version robot that turns away from obstacles using 2 sonar sensors:

And later, as the sensor package included bumper switches and cliff detectors:

Here's a shot of my son's screen as he readies a new bracket design to be printed upstairs on the 3d printer:

What did you play with this week?