Articles

A simple framework using Three.js and MQTT to easily create digital twins

Kubernetes manifests can seem quite daunting at first, but it is important to understand that their apparent complexity is simply a result of the large number of customization options. In the end, manifests are used to deploy resources that interact with each other, which, among others, lead to the correct operations of containerized applications. Consequently, resources specified in a manifest must be configured accordingly. This article aims at explaining how manifests are structured to do so.

A Node.js application which stores data from IoT devices sent over MQTT into an InfluxDB time-series database. It allows the management of multiple data sources into a MongoDB database.

Smart lights are usually some of the first appliances to be added to a smart home. Although those can nowadays be purchased easily from various brands, I wanted to have my own hardware so as to integrate it better with other devices and software. Thus, I decided to an IoT LED controller that I can use in various projects where lighting has to be controlled via network protocols.

RFID tags come in various forms and sizes, from standard plastic cards to chips that can be implanted in one's hand. I got particularly interested in RFID rings, which can be purchased online for less than USD 20$. Those are based on EM4305 chips, which require a compatible reader. Thus, I designed an IoT EM4305 reader that can exchange data over MQTT with other devices.

More often than not, web applications require restrictions regarding who can access the content that they serve. This involves an user management and authentication system, which, if designed inappropriately, can lead to security concerns. However, the development of such system can be time consuming, especially if done repeatedly for multiple applications.

Although probably in the decline, infrared is a common way to remotely control household appliances such as air conditioners or TVs. Being able to turn on an AC unit without leaving the sofa is definitely comfortable, but sometimes it would be even better to be able to do it before even getting home. In order to control those various appliances, I designed a simple WiFi controlled IR emitter.

I am not much of a cook so salads are usually one of my favorite options for a healthy meal. So, just like for everything else, I started wondering if I could make my own. However, I don't have access to a garden so I started looking into solutions to grow vegetables indoors. I settled for hydroponics, which seemed to provide a good balance between yield and operational hassle. Specifically, I went for a Deep Water Culture type of hydroponic system as it is usually considered easy for beginners to setup.

Have you ever left your apartment and couldn't remember if you locked your front door or not? Sadly, if it is unlocked, there is not much you can do about it until you get back home. This system is an attempt to solve the problem. Simply put, it consists of attaching an actuator to the door's original locking mechanism control it with through WiFi.