Need advice for my first project

Other Hardware Home Automation
1

Hello / Good evening makers!

I don't know if I posted it in the right place, otherwise excuse me

I'm new in Arduino and programming (by the way it would be my very first project and to be honest I do not know much about it)
I have a project idea in mind inspired by several other projects discovered on youtube and forums but being a beginner, all this raises for me some questions.
I put you the links below:

Air extractor:

"Connected" lamp:

To describe my project more fully, I would like to create an internal system in my bathroom that would allow me mainly four things:

  • Control the longevity of the lighting (a led strip usually connected to mains) by Arduino by creating a timer system connected to the light (which for example after 30 minutes will extinguish the light by itself since it is amply enough for a shower)

  • Extract the hot and humid air coming off the shower :
    Automatically from a certain threshold of temperature and humidity in the hope of attenuating or removing fogging on windows and mirrors. And manually as on a VMC to also fade the bad odors of pipes that sometimes go back to home.

  • Display the temperature and humidity of the room on a control screen (touch with a graphical interface) that would also allow me to change the settings of the timer to wish and activate punctually the extractor / vmc certainly via a timer system too.

  • Finally, I would also like to integrate a lap counter sensor on the fan of the extractor (which would appear on the control screen) to check that everything goes normally during the tests and that there is no malfunctions.

Now that I have explained the 4 essential points of my project, I will be able to ask you some questions ...

At first I deduce that I will need at least one Arduino (Mega ??), a power supply instead of USB B, a DHT22 (because more accurate than the dht11), one or more relays, one or several fans depending on the amount of suction required, a motor to open the door of the extractor as on the video, a touch screen that would be at least the size of a smartphone, a lap counter sensor, a lot of wiring, a case for the screen and arduino not to deteriorate with moisture and some tools (ex: soldering iron that I do not have) ...

Knowing that this is a fairly ambitious project, would you know if I can code, control, power and "fabricate" all that with a single Arduino or if it would take me more than that to reach my goals?

Thanks in advance for your future responses !

2

The answer is "yes" to everything - particularly the

this is a fairly ambitious project,

bit, but it is easily cut up into easy stages, and it is a pretty typical Arduino project. The fact that you have analysed it well and coherently suggests that you will be fine.

You might not need a Mega in the light of what you describe, but getting one anyway is a rather good idea, as the extra memory it has will cover you for something you have forgotten about, but will remember next week.

3

Hello Altek,
Welcome to the forum.

I don't know if I posted it in the right place, otherwise excuse me

Looks good to me, Project Guidance would also have been a good place for general advice.

Some thoughts that I hope will help.

One Arduino will do the job perfectly well. 2 would be a mistake, trying to get 2 micro-controllers working together on one project is a project in itself. You don't need 2, don't try to use 2.

Buy a Uno, buy a Mega, buy both (assuming cost is not too much of a limitation) and play with them. You need to learn the basics first. There are good tutorials in the Ardunio IDE, on this web site and elsewhere. Start with the simple stuff and work up. Do you know C and C++? I'm guessing not. In case you are confused by the difference, C is the original language, then they added something called 'classes' and called it C++ (This is where the pedanticists jump in and say it's not that simple; it's close enough for what you need to know). Learning C is absolutely necessary, the tutorials will help. You do need to know that Arduino uses a slightly modified version of C++ to the standard version. Arduino C++ has been simplified to make it easier for beginners.

In the very first tutorial in the IDE you will learn to use delay();. I wish that tutorial were not there as it immediately teaches someone new a bad habit. Delay(); can be useful for a quick and dirty test but the more delays you use the more sluggish your code will get. Please don't fall into the trap of using delays all over the place, if you do you will be re-writing your code to get rid of them.

Also buy a touch screen of some kind. I favour Nextion touch screens although there are plenty of others. If you use Nextion see 'Using Nextion displays with Arduino' at the top of the displays' forum.

Unless you are on a very tight budget don't agonise over buying the exact right components first time. If you buy something and play with it and realise something else would be better then you have learned something, had some fun, and got something for what will be a growing supply of parts for future projects.

I have one area of concern for you and what you are doing; do you understand how to work safely with mains electricity? If not please get advice from someone who does. By that I mean someone you can meet and discuss what you are doing, not us who are remote from you. We could give advice but we cannot supervise you. For this reason I, and many others on here, do not give that kind of advice. My general advice is that if you have to ask then you don't know enough to be touching it; get help from someone who can show you and protect you from dangerous mistakes.

Don't be afraid to try stuff. One of the frustrations I have on these fora is questions along the lines of 'here is my code, will it work?' Don't ask that! Just try it and see what happens!

Most important of all is have fun with your project, this is a hobby and like any hobby you should be enjoying it, otherwise pick a different hobby!

4

To be honest you have a lot of fun, and new experiences in front of you. Very important points the arduino is not a power supply and can only supply small currents for a few of the sensors and all external DC grounds must be connected. Relax and take your time. I would suggest you get the arduino cookbook, read it, it is a great reference and starting point. If you can afford it get several arduinos, when you have problems you can always try another one after taking a break. You now come to a major decision point, to I patch and copy or do I learn what I am doing. I would start with the simple blink sketch and play with it until you understand the code and what is happening. Try a few others as well. By this time your other parts probably have arrived. Read an directions that come with it and possibly get the manufacturers data sheet if it is at all possible. If you can afford it a small logic analyzer can be purchased on eBay for less then $10.00, and a multi meter is not much more then $25 for an inexpensive one, these will be very helpful as you get into your projects. Now you have a bunch of stuff you need to understand, it is not difficult, just remember if you do not have an electronics or computer background you are learning another language, it does not happen over night. This will get you started, there will be a lot of other suggestions, take your time and examine them. The only bad question is the one that was not asked. This response is to help you get started in solving your problem, not solve it for you.
Good Luck & Have Fun!
Gil