Your's OTTO

https://github.com/OttoDIY/DIY

Otto_BASIC added functions, gestures or sounds in loop
Otto_avoid Otto will avoid obstacles
Otto_push must change on line 53 Otto.walk(1,1000,-1); to Otto.walk(1,1000,1) to make Otto follow you!
Otto_run will run fast straight forward with this code
Otto_singleladies Dance single ladies by Beyonce
Otto_smoothcriminal Dance smooth criminal by Michael Jackson

It costs less than $15

https://gist.github.com/monhambe

Material:

MINI USB ATmega328P Nano V3.0 (1.99€ / $2.45)
Expansion Sensor Shield Module For Arduino UNO R3 Nano V3.0 (0.85€ / $1)
9gr servo motor (4x2€ / $8.63)
HCSR04 (Robo eyes) 0.72€ / $0.85
wire (0.36€ / $0.45)
buzzer (0.25 € / $0.29)

https://www.aliexpress.com/item/1PCS-Nano-3-0-controller-compatible-with-nano-CH340-USB-driver-NO-CABLE-NANO-V3-0/32684621397.html

https://www.aliexpress.com/item/NANO-I-O-Expansion-sensor-Shield-Module-for-Arduino-UNO-R3-Nano-V3-0/32645527004.html

https://www.aliexpress.com/it