IoT AC Control System
An internship project that connected ESP8266 firmware, MQTT, FastAPI, and a Next.js dashboard for remote AC control across multiple devices.
I built this during my internship at Ellipsis Infotech.
The problem was practical: multiple AC units, separate controls, no shared visibility, and no clean remote management path.
The System
The stack had three parts:
- ESP8266 firmware for IR transmission and MQTT communication
- FastAPI for device registration, command routing, and state handling
- a Next.js dashboard for the operator view
The interesting work was not any one layer. It was getting firmware, backend, and dashboard behavior to line up as one dependable system.
What Mattered
Connected control systems are mostly coordination problems.
The firmware had to stay simple. The API had to keep devices and commands predictable. The dashboard had to show enough state that remote control felt trustworthy.
MQTT fit the problem well because it kept communication lightweight, but it also made state and confirmation more important. A command being sent is not the same thing as hardware being in the new state.
Why It Stayed
This was deployed internship work, not a throwaway prototype.
It also shaped a later personal project: the home bulb control system. Once I spent enough time with MQTT, device state, and remote control, I started seeing the same pattern in smaller everyday problems.