Flir Lepton Raspberry Pi: A Thermal Imaging Project

In this project, we aimed to create a thermal imaging system using the Flir Lepton camera and the Raspberry Pi Zero. The project involved integrating the GPS module, analog transmitter, and Python script to display thermal images in real-time.

Initially, we faced challenges due to the UART controller on the Raspberry Pi Zero being used to receive video buffers from the thermal camera. We found a suitable GPS module with a small form factor that met our requirements for precision tracking while flying drones.

To ensure a strong connection between the transmitter and receiver at distances up to 1.5 km, we opted for a 5.8 GHz analog transmitter commonly used by FPV drone flyers. This allowed us to maintain a stable transmission despite obstacles in the environment.

The display buffer from the thermal camera is transferred as a whole using a serial connection at 115200 bauds, increasing the refresh rate. The Python script running on top of the Linux operating system receives data from the camera and creates a thermal image stream with a resolution of 640x480 pixels, upsampled from the original 320x240 pixels.

The thermal image is not rendered on the Pi Zero itself to prevent any changes or modifications. We chose the Raspberry Pi Zero over other options like the Teensy because it offers video output capabilities and analog output possibilities via WiFi or 5.8 GHz Analog transmission.

During development, we weren't sure about the method of sending the thermal live video to the ground station. The smallest possible module was required, which led us to port the project to the Raspberry Pi Zero. Max Ritter's Thermocam features an UART interface that allows communication and live streaming to a computer via serial commands.

The biggest challenge we faced was integrating the GPS module with the existing system. However, by overcoming these obstacles, we successfully created a thermal imaging system that can provide real-time video output using the Flir Lepton camera and Raspberry Pi Zero.

Flir lepton raspberry pi