This is a birthday party entertainment gadget. It throws individually wrapped, block shaped sweets when someone gets close to amuse the party guests.

The full sequences after detection of something closer than 25 centimeters by the ultrasonic sensor is: Start the accelerator wheel (let it run 5 turns of the actuator, don't wait with program execution), wait a while, turn the push wheel 1 turn (this pushes the sweets under the accelerator wheel and they fly away), raise the mask arm, wait a while, play "take this" sound file, lower mask arm, wait a while, wait until something gets too close, start again.

Of course, being a birthday robot, the looks are important, so the whole machinery is hidden behind a huge amount of lego, as the last 2 pictures document.