my 6 year old son asked for a robot. And I had a RasPi. And I refuse to buy him some cheap plastic toy robot. First because I can do better than that and second because I wanted us to do some project where we can have fun and learn a lot (not necessarily in this order).
We decided that we want to have a tracked vehicle and I found the Dagu Rescue Platform. The thing is smaller than I thought (the platform is 14cm * 10cm), but the 10cm are just right to hold a Pibow Coupe. I really like this small, flat case (especially because everything is still accessible while the raspi is in it). So you can still directly attach raspberry hats on the GPIO pins.
For motor and servo control I got me a Ardafruit Servo Controller and the Ardafruit DC Motor hat. And on top we decided to put a unicorn hat. So on the one half of the robot platform we stacked all the compute stuff (next to the unicorn hat you can see the receiver from an xbox controller for remote control), on the other half (now hidden under the aluminium case) we have the power supply (2 boxes with 6x rechargeable AA Mignons each).
Right now I integrated the unicorn “rainbow.py” example into the robot control software (but I dimmed the values for the LEDs because the lights were much to bright to have this as a colorful night light for my son). On the photos you cannot see the wonderful colors (because my phones camera does not offer manual aperture control).