Articles

Mosquitto is usually the first candidate to come to mind when looking for an MQTT broker. However, by default, Mosquitto manages users using a password file. This makes it difficult to easily add or remove users, especially when the broker is deployed in Kubernetes.

With the COVID-19 pandemic, many of us cannot participate in family gatherings or other similar events in person. Instead, some opt for video-call applications like zoom, but then get constrained to the field of view of camera of the device used for the call.

Earlier this year, a friend of mine was organizing an event to promote eco-friendly behaviors. She wanted someone to talk about our relationship with energy and asked me to give a presentation on the topic, which I agreed to. I wanted the presentation to be entertaining so I designed a set of hardware demonstrations aimed at explaining physical concepts related to energy.

RFID tags are great but often easy to lose. To solve this problem, I designed this case for an RFID tag, which can be worn on one's wrist using a standard watch strap. The case was designed using Fusion360 and then 3D printed.

An image is worth a thousand words and probably even more if comparing their size in bytes. When designing my CMS, I originally intended to store images directly in the article, encoded in Base64. However, this would considerably increase the size of each article, making the whole CMS slow.

Few would argue that having lights turned on in a room without occupant is a waste of electricity. Ideally, lights and other appliances like air conditioners would only be turned on when someone is around. This project is a NodeJS application that gathers data about the occupancy of an apartment and manages appliances accordingly.

An IoT RGBW LED controlled via MQTT with integrated motion and illuminance sensor.

Publishing articles on a website can be as simple as uploading HTML files to a web server. However, writing articles in raw HTML can be time consuming. A content management system (CMS) is an application designed to solve this issue by providing a simple way to create and manage web content directly from the web browser. There are many CMSs available, namely Wordpress or Joomla but I decided to create my own as a form of practice and in order to have it highly customized to my needs.

I found a cheap 4 wheel drive chassis on eBay and decided to make a remote controlled robot out of it. Thus, I made a simple board with two H-bridge modules, an NRF24L01 wireless module and Arduino pro mini.