Arduino, or how to build your own electronic devices

When it comes to making electronic devices and prototypes, the task often seems insurmountable, the complexity of today's devices like smartphones, computers and consoles suggests that only a team of seasoned engineers can pull it off.

Of course, building a console is quite a feat (even if it's not insurmountable, as this hacker explains) but it remains possible to build simple, very useful objects for very little money using open-source prototyping boards thanks to the Arduino project.

The concept

Arduino is a project that is both open-source hardware and software, allowing creators to easily build prototypes of interactive electronic objects.

Generally, an Arduino refers to a basic electronic board integrating a microcontroller as well as all the components needed for it to function, be programmed, and collaborate with other electronic modules.

In reality, the ecosystem brings together several models of open-source boards, an IDE integrating the boards' drivers, a great many libraries, electronic modules and expansion boards but above all: a hyper-active and passionate community.

This is one of the advantages of the Arduino ecosystem, because even without extensive knowledge of electronics and embedded programming, you'll be able to rely on thousands of available tutorials, some of which describe a project similar to yours!

I can already hear some of you wondering: "What's the difference between Arduino and Raspberry Pi boards?"

They have nothing to do with each other! Raspberry Pis are mini-computers that can run different operating systems (mainly Linux and Windows) whereas Arduino boards can only run a single program at a time, which resides in their very small memory.

One uses a microprocessor, while the other uses a microcontroller that is far less powerful (but also far less power-hungry).

The features

Here's a short list of the main features found on Arduino boards:

• Digital inputs-outputs (values 0 or 1)
• Analog inputs-outputs (values from 0 to 1023)
• An internal clock
• Flash memory
• A regulated power supply voltage output

Arduino boards are programmed in C/C++, thanks (notably) to the Arduino IDE, which compiles the program into a set of instructions the microcontroller can understand.

The boards

Classic Arduino

There are many boards of different sizes featuring more or less powerful microcontrollers as well as other differentiating capabilities.

From left to right, we have:

• An Arduino Nano the size of a USB stick, perfect for your portable smart object projects running on battery.
• An Arduino Uno the size of a credit card, useful for your home automation projects, for example.
• An Arduino Mega twice as large, sufficient for great robotics projects.

The choice of one board over another is often guided by the number of inputs-outputs required for the project to work properly, but some boards come with very useful additional features.

ESP32

The ESP32 is the perfect example of a board with incredible potential while still benefiting from the simplicity of the Arduino ecosystem.

A tiny bit bigger than an Arduino Nano, the ESP32 has three distinctive features that make it a top choice for connected object projects:

• A 3.3V power supply, making the board very energy-efficient and able to run for days (even weeks) on a properly sized battery.
• A Bluetooth BLE chip
• A Wifi chip

If you already enjoy creating Arduino projects, I can only recommend that you try this board!

A few examples

There are hundreds of modules compatible with Arduino boards, and it's worth keeping in mind that this remains an electronic module like any other, so it's compatible with all the electronic components available on the market!

Between ultrasonic proximity sensors, sound sensors, infrared sensors, temperature sensors, etc... you'll be able to build an incredible number of objects useful for your daily life or for your loved ones!

For my part, I've published open-source projects available right here, one based on an Arduino Nano, and the other on an ESP32:

• An automatic watering system for indoor plants: https://github.com/NicolasBrondin/power-plant
• An MP3/White noise player for babies: https://code-garage.fr/blog/fabrication-lecteur-mp3-open-source-sur-esp32-avec-arduino