Articles

This project consists of an HC-SR501 PIR motion sensor and a DHT22 temperature and humidity sensor connected to a Wemos D1 mini, an ESP8266 breakout board.

One of the companies I used to work for had a serious bathroom issue: My floor had only three toilet stalls for about 200 employees. There were countless times when I would walk all the way to the bathroom only to find all stalls occupied. I built this simple system to quickly identify whether one or more stall were. It consists of an IoT sensor installed on the bathroom stalls' door and an indicator placed somewhere easily visible.

One of the companies I worked for put a lot of importance on safety. As a way to improve the employees' awareness of danger, there would be regular meetings during which participants would need to identify dangerous points in a picture. The results were written down and archived on paper, which I believed could be improved. So, I created this web application.

Most banks nowadays provide e-banking interfaces that allow clients to monitor the state of their accounts. However, each bank has its own system and the provided interfaces sometimes lack functionalities. Consequently, I decided to create my own finance dashboard, that combines information regarding multiple accounts. Currently I use it to keep track of my bank accounts balance over time as well as provide a breakdown of my transactions.

I've been using&nbsp;<a href="https://www.home-assistant.io/" rel="noopener noreferrer nofollow">Home Assistant</a>&nbsp;to control my home IoT devices for a while. Although it fulfills all my needs, I wanted to make my own system so as to get a fully customized smart home control panel and learn how to build such an application in the process.

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.

When you don't know how much power your air conditioner draws, it's easy to leave it running without feeling too guilty. And then the electricity bill comes...

RFID is a conveninent technology for access control and authentication. In this project, I connected an RC522 RFID reader to an ESP32 in order to use it for IoT applications. Additionally, to provide feedback to the user, the ESP32 is also connected to an SSD1306 OLED display and a buzzer. I chose an ESP32 over an ESP8266 simply because of the amount of GPIOs required.

Keeping track of one's body weight usually involves manually writing down measurements on a spreadsheet or similar. To automate the process, I removed the electronics of a cheap scale, keeping only the load cells, and replaced it with my own.

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