How to handle power distribution on a robot?

Question

Our team just finished the FRC competition and I am trying to learn more about robots in general. I'm trying build a robot in a similar setting than the FRC competition. However the RobotRIO is out of my budget.

I'm currently set on buying a Raspberry PI 3B as main controller board as replacement for the robotRIO.

However, I do not quite understand how I'm going to power 12v motor. In our FRC build we had this power distribution panel, but I'm pretty sure I will fry my raspberry PI.

I believe I need some kind of power distribution board to have 5v and 2.5a for the Raspberry PI. And also 12v on some other pin. Does this exist or am I looking for something that do not exist.

My build would be powered by a 12v battery like these Interstate Batteries (am-3062).

Answer 1

For power management, you can use either a DC/DC Convertor, a linear regulator, or a combination of the two.

DC/DC Converter

A DC/DC Converter changes DC voltage levels. Three common types are:

1. Buck Converter: Takes a higher input voltage to a lower output voltage
2. Boost Converter: Takes a lower input voltage to a higher output voltage
3. Cuk Converter: A combination of a boost and buck converter that can take an input voltage and either boost or drop it.

Linear Regulator

A linear regulator also takes a higher input voltage and provide a lower output voltage. Typically, the output voltage is "cleaner" with less noise than a DC/DC converter and you will find regulators used to power embedded computers and microcontrollers.

System Recommendations

You can use a Cuk Converter between your battery and the 12V motors. You can also use a 5V regulator to get the necessary power to your Raspberry Pi. Instead of using the power distribution panel, you can try everything on a breadboard and then move to a perfboard. Many of these parts should be available on Digikey, Adafruit, or the electronics vender of your choice.