Yozh is powered by 4 AA (also known as LR6) batteries, inserted in the battery compartment at the bottom of the robot. It is highly recommended that you use heavy-duty rechargeable NiMh batteries such as Panasonic Eneloop Pro. You will also need a charger.
The robot also contains power switch, for disconnecting the battery, and a power indicator LED.
The robot contains a voltage regulator, which converts battery voltage to regulated 3.3v. Most of the robot electronics, including the microcontrollers and most of the sensors, are powered from 3.3v bus. Motors, servos (if connected), buzzer, and reflectance array are powered directly from the battery.
Note that NiMh batteries are not designed for high currents. Depending on the battery, you can expect 4-5A maximum; this would be enough for all on-board electronics and motors, and leave 1-2A for any electronics you want to add. This should be OK for micro servos and a couple of sensors, but if you want to use standard size servos or power-hungry devices such as AI cameras, you might have issues.
Connecting the ItsyBitsy microcontroller to a computer by USB cable provides power to 3.3v bus, even if the main battery is off. This would activate the microcontrollers and some of the electronics, but not the motors or servos.
You can check the battery voltage in software, using
battery() function as
described in Yozh Library Guide. Fully charged NiMH batteries
should give about 5.5v.