What is Arduino? What model to buy?

Arduino is a programmable board with digital and analog inputs and outputs, whose low cost makes it ideal for starting in automation or carrying out small home projects in electronics and robotics.

This means we have a small “automaton,” capable of receiving information from the environment (sensors) and performing actions (actuators, motors…), according to a program that we input with a computer, and that can execute autonomously.

To give you an idea, until shortly before the appearance of Arduino, commercial/industrial automatons with similar capabilities cost several hundred euros.

These types of automatons are used to interact with and control all kinds of systems, from installations in buildings (climate control, pumping), industrial installations, vehicles, robots… any physical system that needs to be controlled electronically.

Arduino is an excellent platform for practice and learning. Both for programming, electronics, as well as an introduction to automation and robotics (and with it mechanics, hydraulics).

In addition, it will bring you hours and hours of fun working on your robotics and electronics projects (for less than a night out), which is always a good thing.

To start with Arduino, logically, the first step is to buy one. That’s why we will look at the different available models.

Which Arduino model to buy?

There are many Arduino models available, which can be a bit confusing for new users. When choosing, it is common to look at the number of inputs and outputs it has, especially the analog ones since they are usually the ones that restrict our project.

In the following table, you can see the most common Arduino models, with their most important features and a reference price when buying them on eBay or AliExpress by searching with international Chinese sellers.

You can find a complete list of the different models and revisions at https://es.wikipedia.org/wiki/Arduino.

It is most common that to start, you use an Arduino UNO r3. This is the most standard model and is the board you will use regularly. For certain large projects that require handling a significant number of motors or servos (robots, CNC machines, 3D printers), it may be necessary to switch to a model with a greater number of outputs, especially analog ones. In that case, the norm is to use an Arduino MEGA r3.

On the other hand, the Mini 05 model is for advanced users. It is a board that costs only 2.5€ and is really small, designed for final applications, that is, when you are going to leave the board permanently connected (and therefore you are going to “lose” it). It comes without connection terminals; they need to be soldered, and to program it, a USB FTDI adapter costing 3.5€ is required. At expert levels, this is practically the only board model you will use since, if a large number of inputs or outputs are needed, it is more economical to form a network of 3 or 4 mini boards, and you obtain a capacity superior to a MEGA.

Therefore, final recommendation. Buy an Arduino UNO, which will be your standard development board. When you become advanced, buy one or two Arduino Minis, along with the programmer. And only for specific projects where the UNO becomes insufficient, and if you do not want to complicate your life by making networks of Mini Arduinos, or if you need to use additional serial ports, you can use a MEGA.

Only for the domestic sector?

Arduino is flexible and reliable. So, why have we mentioned domestic projects? Why not in commercial or industrial applications? It’s a good debate.

This is something that may tempt you at some point. In fact, we know that people create commercial products based on Arduino. Initially, it is most likely that everything will work very well.

However, if one day you have to control (for example) the climate control of a sports complex, where just the chiller costs 250,000€… it will seem reckless to install a 15 euro controller.

In that case, you would probably prefer to install a general automaton that costs 500 to 1000€, which offers you a certificate and a guarantee for your peace of mind, and to protect your signature (although that’s up to each one’s professional judgment).

For this reason, it is often associated with the domestic sector. But the good news is that everything you have learned about electronics, automation, programming, and telecommunications can be directly and easily applied if you need to use a more expensive automaton.

Because, more or less, electrons move the same way (in fact, they move exactly the same way) and things are programmed more or less the same way.

Having made the introductions, in the next tutorial, we will see how to install the Arduino development environment to start developing.