View attachment 208904
Sure looks like it's for Mega to me...

Mea culpa! I was seeing the board upside down.

 

Let’s do a count of the required pins.

• 5 sensors requires 5 pins
• 5 stepper motors @ 4 pins each requires 20 pins.
• 8-10 switches requires 10 pins

The total is 35 pins. The Mega 2560 has 54 GPIO pins. Plenty of room for expansion without IO extender boards.

Sorry to clarify again, there are 5 ultrasonic sensor which need two pins for each sensor.
Best