We remix the Bender by installing a PIR (Passive Infra Red) Sensor in the belly with an Arduino nano to let the eyes flashing when a motion is detected in front of the bender.

https://www.amazon.com/s?k=pir+sensor+arduino&ref=nb_sb_noss_1

https://www.amazon.com/s?k=arduino+nano&ref=nb_sb_noss_1

https://www.gearbest.com/led-light-bulbs/pp_625950.html

You'll find the schematic for connection of the Pir Sensor and the led in the images. The code for the arduino is stored on Github here : https://github.com/renaudrenaud/benderpir/tree/master

And you can see it blinking here https://youtu.be/gLy1qyILlII or here https://youtu.be/I3-n-2ref5k