In NezaRobot, I only use BBB to control 6 servos and 1 CAN bus and USB WIFI.
ehrpwm0A-0B, 1A-1B, 2A-2B, 3 groups PWM timer.
1 CAN Bus:
CAN bus needs a converter to convert +3.3V level to CAN bus standard.
1 serial port:
It is for debugging
Other pins are not used.
I use KiCAD for draw electronic schematics. It is open source and free.
From above figure, BBB has +5.0VDC connector, 1 USB WIFI, Serial port, CAN Bus, 6 PWM servo controllers.