There is an enormous variety of electronic gadgets you can use in your STEAM classes. With the growing number of DIY and maker-oriented electronic tools such as Arduino and Raspberry Pi, along with their ecosystems, many are finding their way into education, though with mixed results.
Among all the DIY electronic platforms, the BBC Micro:Bit stands out because it was designed specifically for school use. This means that all the key elements of its ecosystem — HARDWARE, SOFTWARE, and COMMUNITY — are built and maintained with these priorities in mind: YOUNG STUDENTS, TEACHERS, and SCHOOLS.
The BBC Micro:Bit is quite a capable board on its own, featuring an LED display, numerous sensors, and wireless communication. However, to use the Micro:Bit as the brain of a cardboard robot, additional accessories are needed to enhance its capabilities.
In this guide, I will introduce you to the most basic and essential accessories you might need to begin your journey into robotics with the BBC Micro:bit
Minimal set of electronic components
To get started with cardboard robots you need a really small set of electronic parts:
- BBC Micro:Bit
- Servo connector (female) to three alligator clips adapter cable
- 2 x AAA battery pack – with AAA alkaline batteries
- One servo motor – depending on the project 180deg or 360deg (so in fact you should have two of them, but only one can be connected at a time)
With this setup you can get a really cheap robotic kit (cost altogether around 25USD) that will allow you to make all of our one-motor projects.
With a help of the adapter cable you can connect the servo motor directly to the Micro:Bit, even tough the board can provide very little power directly from the 3,3V pin (about 90mA) it is barely enough to power one micro servo.
PROTIP – Micro servos with plastic gears (usually in blue housing) require less energy than the one with metal gears (usually in black housing like Tower Pro MG90S) – so if you plan to power it directly from the Micro:Bit board choose the plastic blue ones
PROTIP#2 – If you power the board with AAA batteries you have to use ALKALINE BATTERIES they provide 1,5V each so two of them give you 3V which is already below required 3,3V but will get the board and one micro servo running for quite a while. Regular AAA Ni-Mh rechargable batteries like Eneloops etc. provide only 1,3V each so two of them give only 2,6V which is not enough to drive the servo.
Suggested electronic parts
- BBC Micro:Bit
- Micro servo motors – two types -180 degree and 360 degree (full rotation)
- Micro:Bit adapter to connect servo motors
- Magnetic micro USB cable
1. BBC Micro:Bit
We love Micro:Bit since it introduction in 2016 and now as it grown mature with software, users community and educational content it is a no-brainer to make it a heart of an educational-centered STEAM project.
Micro:Bit is much more capable than Arduino and much simpler to use than Raspberry Pi. Packed with built in sensors and wireless connection capability this board is great for a basic robot controller.
Micro:Bit has plenty of onboard sensors:
- buttons
- accelerometer
- magnetometer – compass and magnet sensor
- light sensor
- thermometer
- capacitive touch sensor
- analog pins
For basic robotics projects you can easily go on with the builtin sensors so you need no extra accessories for the board.
2. Servo motors
The only external components you need to build a simple robot with a Micro:Bit board are motors. We suggest using only micro servo motors as they can operate on 3.3 volt signal provided by the Micro:Bit and you can get them in two modes:
- 180 degree – for pivots, gripers, arms etc.
- 360 degree – full rotation – for wheels
3. Micro:Bit adapter
The main limitation of Micro:Bit when your goal is to build a cardboard robot is that you need some kind of adapter to connect motors and provide power supply. For the sake of simplicity I suggest using Elecfreaks Ring:Bit V2.
This adapter is minimal in design and capabilities, has only three I/O sockets but together with a Micro:Bit board provides a neat little package with power supply through 3xAAA batteries. It is more than enough for small robotic projects.
If you have basic electronic experience you can workaround and connect servo motors to Micro:Bit without the adapter, or make this kind of board on your own.
Other adapters
There is of course a huge choice of more capable Micro:Bit adapters with much more features. For the sake of simplicity we suggest only basic solutions with micro servo and we find smaller adapters with less features more suitable for basic school needs. To go on with any other adapters or Micro:Bit extensions you will have to make some modifications in our robot designs,
4. Magnetic micro USB cable
This accessory is not necessary but it is ESSENTIAL to lenghten your Micro:Bit board lifetime in school environment when it is tossed around from one kid hands to another.
Micro:Bit is rather solid board with no specific parts to bend/break/tear apart but it weakest point is definitely a MICRO USB PORT. Makecode software uploads the code only via usb cable and as you build a moving robot you will likely want to plug and unplug it many times uploading new iterations of your code and testing it. When this process is in hands of your inattentive teenage students damage of the usb port is only a matter of time.
Magnetic cable solves this problem, you only plug the connector to the usb socket once and then use the magnetic plug to connect the board to the computer. If your robot falls to the ground or moves unexpectedly, magnetic plug detaches and keeps the usb port safe.
Improve your classroom experience
Printable Robot Templates
Downloadable PDF file with vector-based printable designs of all our robots in A4 format.
Micro:Bit Robotics – Video course
Get a practical insight how to use BBC Micro:Bit in the classroom. Learn how to code cardboard robots with useful lesson ideas.
Cardboard Robots Inventor Kit
If you need a complete kit with all the tools and electronics to build Cardboard Robots consider buying our kit 🙂
Robot Stencils
Set of reusable robot stencils to help your students build cardboard robots faster and easier.