Dan’s Diary (November 2023)

Well, a lot has happened. Shortly after the first post of this webpage, it rained for a few days here in Málaga, the sewage system got clogged up and… Well, I won’t get into much details, I’ll save you the trauma.

We had to disconnect everything from my room, including the PC where I was creating the animations to the BLDC motor blog that will be done in (rapidly checks the forecast) no time! I haven’t had access to the PC for a long time until my landlord finished the repairs. So now I’ve got to put in some work to compensate.

So without further ado, what happened in the meantime?

New studies!

I have enrolled to study a Master on Automatic Systems at SEAS! I’ve already finished a subject, Fundamentals of Electric Engineering (bearing in mind that I’m a teacher that verses on just that, it was piece of cake 😋).

I’m really close on finally ending the next one. It’s about automatic systems only using electric components, such as commutators and relays. They’ve tasked me with building my own car wash machine, and it was looking really good until the program I was using (CADeSIMU 👎) started glitching. It didn’t allow me to modify the circuit any further so I had to end it all as it was. Bummer…

If you are curious about the circuit, just write me in the comments bellow.

Oh, and here you have a shitty drawing I did to show my teacher what the hell I was talking about the sensors to automatically move the brushes of the carwash so that it followed the profile of the vehicle 🤗.

I have also enrolled on the Computer Vision and Deep Learning Master Program from OpenCV University. It’s funny how I got this idea…

Getting off track… Measuring temperature by taking photos

I was trying to measure the temperature of the 3D printer’s enclosure I built (I’m hoping on creating a post about this in the future). It seemed that the thermometer ICs I installed weren’t reliable enough as they were mostly showing two Celsius degrees of difference whilst being on the same spot. As the stingy person I am, I decided to not buy any more chips and to use instead my multimeter’s thermometer.

Oh but, there was a catch! You see, my multimeter only showed the temperature on its whimsy LCD screen. That’s no way to monitor temperature! I need the microcontroller inside the enclosure to get the temperature and, based on that, turn on the fans. So I did what any sensible person would do: read the temperature by recording the multimeter with a camera! Damn I’m difficult 😂.

I tried creating a demo with a photo taken with my mobile phone and I discovered OpenCV. I tried it and I have to say it thoroughly engaged me. It also gave me the opportunity to learn more about Python! And after fidgeting with it for a whole evening, I got a program “working”.

There’s a lot of room for improvement, but hey, it’s something. I wanted to implement this on an ESP32-CAM I had lying around, but I never got around to do it (basically because I did not have access to any equipment because of the flooding), so this project will fall, at least for now, on the “Daniel-From-The-Future’s To-Do List ©”.

Oh yeah, and the multimeter broke… It measured a comfy 30ºC while sticking the thermostat inside a lighter’s flame, so in conclusion I did everything for less to nothing 👍.

On a lighter note…

My own online portfolio?!

WHAAAAT?! Yes! I’ve been doing just that! You can see it on the frontpage!

I have to say that the most difficult part for me of building a webpage has been learning CSS and making everything KEEP IT’S POSITION! But I also have to say I’ve gone crazy doing little quirks, like the animation for the “Contact me” button (which at the moment of writing doesn’t do anything but looking fancy).

As well as that, my name has a subtle color effect that tracks your mouse. It also has wavy hand that salutes at you when you first enter the webpage and when you hover the mouse over it (refresh the page if it looks cut).

Another one of the (kinda) impressive things I’ve added, it’s the hecking screensaver of my End of Degree Project. So the project is in reality a digital audio pedal, a Looper pedal to be concrete. I built it with an ESP32 at its core, a TFT screen with a rotary encoder and several push buttons form the UI, and some complex analog filters to adapt the input/output audio signals. Its user interface was rather simple (and I didn’t have enough time to finish it completely) but it had really cool animations (that serve zero purpose but were hard as 🐸 to do!). Take a look:

I really want to delve deep into these animations. Do you know why they were so hard to implement? Because the speed to print to the TFT screen was very limited, specially if you work in bitmap mode (meaning that you give to the device the whole screen image to be written). So you’ve got to get creative! What I did was to double buffer the screen so that when printing it only printed the chunks who were “a lot different” from the last one. In other words, I had designed a compression algorithm in real time for a microcontroller! And it worked like a charm!

At the starting of the project, the slide-in slide-out effect you see was really stuttery, leaving a lot of printed yellow pixels that wrecked the whole image. And now look at it, so smooth… And it did not affect the performance of the pedal (FreeRTOS + ESP32 ❤!).

Another thing that was really difficult to do was to do the animation OVER the elements behind the curtain! It looks effortless now, but… Oh boy was it difficult back then!

So as a programming exercise and to force me to learn a little bit of JavaScript, I implemented the screen saver on the canvas object functions (aka. 2D Context) on plain JS, and here is the result.

Try to click over the icosphere 🎶!

Maybe I’ll talk on another post on the mathematics behind a “virtual camera”, but there’s already a lot of content on the internet explaining how it is done, so unless you ask for it…

And finally:

Porting this website to WordPress.org

Not a single day had passed after I started this webpage when it became clear to me that I had made a terrible mistake: I hosted my webpage on WordPress.com. I paid for a Personal Plan which I found quite cheap to buy, bearing in mind it also came with a free domain. I hoped that I could add my own JavaScript code to my server, but I was wrong. If I wanted that, I should buy a Business Plan to add my own plugins, and the price would rise from 4€ to 25€ per month! Well… That’s way beyond my budget!

I think I should explain what the hell I’m talking about…

Ok, so suppose you want to start your own blog or an online shop. There are two fundamental components you’ll need to check out: a hosting service and a domain. The hosting service is where your HTML, CSS and other server files will be stored, publicly available for anybody to have access to; but for them to access, they’ll need a direction to search for. That’s the domain, the name you put over the server’s IP to make it manageable for ours, puny humans.

There are companies who take care of everything for you so you don’t have to mess with all the server side stuff (backend) and you can center on creating your content and making it all look beautiful (frontend). Some of these companies are for example Wix, Weebly, Blogspot and WordPress among many others.

About the latter one, there are two completely different things named WordPress: you have the Open Source WordPress (also named WordPress.org) and the company that takes care of the hosting for you (WordPress.com). WordPress is the web content management system that keeps this webpage running. They have made a really intuitive interface to create webpages and it’s really really customizable with lots of visual themes and plugins to do a lot of wacky stuff. Remember, this is Open Source, meaning its free for anybody, so you can learn a lot by yourself by hosting your own webpage on your computer and trying all its features.

The WordPress.com have the same Open Source software running under the hood but they also host (publicly) your webpage, with the caveat you have to pay to have some of the features that in the original WordPress are free to begin with.

That’s a really big simplification, but please don’t think I know much about the subject, I’m new at this!

So about my personal experience, as I said, I started this blog in the .com site, got myself my own personal domain, which was really cool, and there I did the first post of this blog. I can’t remember what I wanted to add, maybe it was a video or something like that, and it didn’t let me do it. I upgraded to the next available plan after receiving a discount coupon, and imagine my surprise when I noticed that the plan I had bought didn’t enable plugins and I had to pay almost six times what I initially thought I’d be paying for the plan that enable them.

After a thorough investigation, I found Hostinger, which is where I currently store dabecart.net. I’ve had little trouble with them and the support personnel normally ends conversation with a funny GIF, so yeah, they’re amazing.

To sum up!

Hope you liked the long post, there are so many things to talk about… I’ll be happy to hear your suggestions and opinions on the comment box down below!

I hope I get enough time to finish the drone now that I have my desk again, but yeah, you’ll be hearing about me in no time!