I have questions about my final project

I will heat 36 NiChrome wires depending on the wind predictions. I planned to use MOSFETS to switch the wires ON/OFF. But the problem is: If I switch only one wire on, all the power from a power supply will just go to this one wire and this wire will be very hot.

So I need a way to restrict the power according to the number of wires. I could use PWM (Pulse With Modulation) and make the pulse shorter according to number of MOSFETS that have to be powered, but this is a 'software' solution and is complex. If I make a mistake my project will literally be in flames. ;-)

Is there an other way to reduce power? (total power will be around 100mA per wire)

[Some more info about this on this Fab page] (http://fabacademy.org/2020/labs/waag/students/harm-vanvugt/posts/2020/06/18/Final-Electronics.html)

@harm.vanvugt I think you will need to use something like PWM, but the software will not necessarily be very complex. If you have all your wires set up so that you can individually turn them on or off (probably using a matrix with MOSFETS on row/columns), then you can simply do something like this (pseudocode):

while (true) {
  for (int i = 0; i < 36; i++) {
    if (is_channel_active(i))
      turn_on_channel(i);
    delay(ON_TIME_MS);
    turn_off_channel(i);
  }
}

Now probably you would want to implement this using some hardware peripheral rather than sucking up all your CPU time for this, but the basic idea is the same: choose how long a wire should be on at a time, for example 2ms. Then every 2ms go to the next wire, and turn it on if it 'wants to be on', otherwise just wait 2ms.

This way every wire is either completely off or on for 2ms every 36 * 2 = 72ms, no matter how many wires are currently 'active'.

Hi, i'm having some touble to find some background for my final project, because the search engine on the fabacademy page won't give me relevant info. my final project is called smart curing station. basically is a box with a rotating table and some uv lights to cure resin based prints in those days when it's cloudy outside or to dark to cure the pieces with sun light... but each time i use words like "resin" "curing" "UV light" and so the search engine give me stuff like molding and casting weeks from prior years but not really final projects aimed to use UV light to cure resin. http://fabacademy.org/2020/labs/ciudadmexico/students/luis-hernandez/final-project.html this is my final project page if you like to see what i trying to do with this. Thanks.

My final project question is ...

Maybe you could use Google Search tricks to exclude words or use quotes to use entire sentences - https://www.lifehack.org/articles/technology/20-tips-use-google-search-efficiently.html ?

The search box uses Google as a back-end, so any of those filters will work.

@luis.hernandez, for this issue to be helpful it would help to pose a more specific question on what help you're looking for (unless it was just on how to search).

Hey, guys, I am working continuously on my final project and just need some ideas on this matter and some suggestions, can you evaluate my ideas and give me some suggestions on that. http://fabacademy.org/2020/labs/akgec/students/pulkit-talwar/projects/Final%20project/ , this is the link for my final project page

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