I really don't know what else i could put in there. That's literally it. I didn't do anything novel with the electronics. it's literally a shield on top of the mega with all the servos plugged into it. the battery doesn't matter. it's not even plugged in.
If you want the link to the shield it's here: https://www.ebay.com/itm/MEGA2560-ATmega2560-16AU-Sensor-Expansion-Board-Sensor-Shield-V2-0-for-Arduino/162145159784?hash=item25c09aca68:g:xOAAAOSwqfNXj09C
The link to the board is here: Mega 2560 R3 Atmega2560-16au 16u2 Compatible Board With USB Cable for Arduino for sale online | eBay