There are now several versions of the Raspberry Pi on the market and we are often asked why we include a Pi 3B in our kits instead of a Pi 4.
The model numbers for the Raspberry Pi are based on the order in which the models were released--it is not an indication of the superiority of any particular model. Instead the different models available are appropriate for different types of projects. Since Level D of our Intro to Robotics program involves building a fully mobile robot, the Pi 3B is the superior model for such a project:
A Robot is Less Fun if You Have to Plug It In: Ideally a mobile robot should be powered via a battery pack (if you need to use a cord to power your robot, your robot's range will be pretty limited). The Pi 4 uses over twice as much power as the Pi 3B. Finding a battery pack to power a Pi 4 is not only be difficult and expensive but there are potential safety issues with a battery pack containing that much capacity (think fire).
- You'd Need to Keep the Pi 4 Cool: The increased power consumption of the Pi 4 also increases its cooling requirements over the Pi 3. At this time, the Pi 4 really needs external cooling and generally that means attaching a fan. Unfortunately there is only one port available so you can attach either a fan or a GPIO header but not both. Without a GPIO header, you can't attach the Pi to the breadboard containing your robot's electronic circuitry.
If You Are Interested in Using a Pi 4 for Other Purposes...
The Skills You Learn in Our Course are Transferable to a Pi 4: While a Pi 4 may not be the right model to use to build a robot, there are some amazing things you can do with them (see below). If you decide to purchase and use a Pi 4 for other purposes in the future, the Raspberry Pi and coding skills you've learned in our Intro to Robotics course are fully transferable to the Pi 4.
- The Pi 4 is an Amazing Step Toward an Affordable Desktop Computing Solution: The Raspberry Pi Foundation's stated goal is to provide an affordable computer option to everyone around the world. The release of the Pi 4 is an impressive step toward that goal. The computing power of the Pi 4 makes it an excellent replacement for a desktop computer and still retains it's very small price tag.