Update #2: Firmware 2.48 is now out and supports the updated ArduCAM-M-2MP Plus camera
Update #1: Patrik Thürlemann has created a nice 3D printed enclosure for the radiometric version of the device, check it out here.
The DIY-Thermocam is a low-cost, do-it-yourself thermal imager, based on the popular FLIR Lepton long-wave-infrared array sensor.
The aim of this project is to give private persons, educational institutes and companies access to a portable, affordable and customizable thermal imaging plattform.
There are various applications like finding heat leaks in the insulation of buildings, the analysis of electrical or mechanical components, the detection of persons / animals or even mounting it on a drone, together with the additional video out module.
Constructed as a self-assembly solution, the DIY-Thermocam allows you to take advantage of the versatile possibilities of thermal imaging and to save money at one go.
Everything, from software to hardware, is completely open-source! This allows everyone to modify or extend the functionalities of the device to their own needs!
A scientific paper is also available, giving an overview about the whole project and its capabilities.
HOW TO MAKE IT
You can make your own DIY-Thermocam V2 at home easily. For the tools, you only need a simple soldering iron, some solder tin, a nippers and a screwdriver. The design of the PCB is very basic: No SMD components, only big through-hole parts and modules. The enclosure can be assembled easily only with bolts & nuts, no glue required.
An illustrated assembly guide will lead you through the process of constructing the device, step-by-step. You should have soldered at least one small project before, but with that experience you should be fine.
The DIY-Thermocam works with the FLIR Lepton2.x (80 x 60) and the FLIR Lepton3.x (160 x 120) LWIR sensor, including the radiometric versions (Lepton2.5 only at the moment). The hardware revision is detected automatically by the firmware on startup and you can change the sensor just with your fingers.
The Lepton2.0 and Lepton3.0 sensors do not have in an internal calibration. An external spot sensor, the MLX90614 is used to generate a transfer function for raw values to absolute temperatures conversion. When using a radiometric Lepton (Lepton2.5 or Lepton3.5), the spot sensor is not required.
In order to make your own DIY-Thermocam V2, please use the part list below to acquire all the components on your own. Digikey.com offers free international shipment for all orders over 100€, so I recommend buying most of the components from them.
You can find all of the screws, bolts, nuts & washers at Ettinger and maybe also at a local construction market near you. If you do not have a VAT and still want to buy the components from Ettinger, write a mail to [email protected] and ask for a quote.
I do not offer pre-assembled devices and am also not responsible for the quality and completeness of the kit from GroupGets.
|FLIR Lepton (Shuttered)
Long-wave-infrared array sensor
| Lepton3.5: Digikey.com or GroupGets.com
Lepton3.0: Digikey.com or GroupGets.com
Lepton2.5: Digikey.com or GroupGets.com
Lepton2.0: Digikey.com or GroupGets.com
|FLIR Lepton Breakout Board Interface the Lepton over SPI / I2C|| Digikey.com
Spot sensor for absolute temperature measurement - not required for Lepton2.5 / Lepton3.5
Cortex M4 Microcontroller
|SanDisk 8GB microSD card
Can be any size, but needs to be Class4 microSD
Visual camera module
|3.2" TT LCD Display Module
Configuration: Interface: Pin Header Connection-4-wire-SPI, Power Supply: 5V, Touch Panel: 3.2" Resistive, Font Chip: None
|3.7V Lithium Polymer Battery
Max. dimens.: 60mm (w) x 55mm (l) x 6.5mm (h)
|Printed Circuit Board
89.4mm (w) x 68.4mm (h), 1.6mm thickness, 2 layers
Or use the gerber files
2D laser-cut from 3mm black acryl plastic (one side frosted)
Or use the design files
|TP4057 Charging Module
Including charging LED
5V voltage booster
USB power switch
PCB Lipo Connector
SD slot for the SD card on the PCB
Short microSD to SD adapter for the internal storage card
40-pin 2.54mm female header
|Lepton board connector
8-pin 2.54mm female header
|Pin header strip
40-pin 2.54mm male header
|Digikey.com (2 pcs)|
Holder for the coin cell battery
|CR1220 coin cell battery
Battery for the real-time-clock
|4.7K 1/4W 1% resistor
|Digikey.com (4 pcs)|
|10K 1/4W 1% resistor
|Digikey.com (2 pcs)|
Double-sided adhesive tape for the lipo protection on the PCB
Or use any thick tape
|Angled microUSB cable
For connection of the Thermocam to the PC and charging of the device
Or use any USB cable
Used as a stand for the device
Or use any tripod
|Screw M2x10 (Details)||Ettinger.de (6 pcs)|
|Spacer M2x3 (Details)||Ettinger.de (6 pcs)|
|Spacer M2x3.5 (Details)||Ettinger.de (2 pcs)|
|Screw M2x8 (Details)||Ettinger.de (5 pcs)|
|Screw M2.5x6 Black (Details )||Ebay.com (8 pcs)|
|Standoff M2.5x12 (Details)||Ettinger.de (4 pcs)|
|Standoff M2.5x11 (Details)||Ettinger.de (4 pcs)|
|Standoff M2.5x5 (Details)||Ettinger.de (4 pcs)|
|Nut M2 (Details)||Ettinger.de (5 pcs)|
|Nut M2 Plastic (Details)||Ettinger.de (6 pcs)|
|Washer M2 (Details)||Ettinger.de (3 pcs)|
- Fast ARM Cortex M4 processor (240MHz), based on the popular, Arduino compatible Teensy 3.6
- 160x120 (Lepton3) or 80x60 (Lepton2) long-wave infrared array sensor for live thermographic images
- Frame rate of up to 9 FPS (US export compliance) over the serial connection, 5 FPS on the device itself
- 2MP visual camera to capture optical images, that can be used in a combined image
- MLX90614 single point-infrared sensor for high-precision spot temperatures (10° FOV)
- HDMI or analog video output capabilities (640x480 pixel) over external video output module
- 3 operating modes: thermal only, thermal + visual, video recording
- 18 different color schemes including rainbow, ironblack, grayscale, hot & cold
- 3.2 inch LCD touch display with bright colors, wide angle and resistive touch
- Save thermal and visual images with a resolution of 640x480 pixels on the device
- Save real-time videos and interval images with different time-lapse settings
- Up to 8GB internal storage, accessible as an exchangeable SD / microSD slot
- 2500 mAh lithium polymer battery for long operation time (4-6 hours)
- Open-source firmware written in Arduino compatible C/C++ code
- Regular firmware updates with new features, flashable over a standalone firmware updater
- Standalone thermal viewer application to save high-quality thermal images & videos on the computer
- Fully compatible to the comprehensive thermal analysis software ThermoVision by Joe-C
- Use simple commands to receive all thermal & configuration data over the USB serial port with high speed
|Thermal resolution||80 x 60 or 160 x 120||160 x 120|
|Thermal sensitivity||< 0.05° C (50 mK)||< 0.06° C (60 mK)|
|Thermal temp. range||-10° C - +140° C or -10° C - +450° C (Lepton3.5)||-20° C to 250° C|
|Field-of-view (FOV)||56 deg HFOV, 71 deg diagonal||45 deg × 34 deg|
|Display||3.2" 320x240 , touch input||3.0" 320x240, no touch input|
|Spot sensor temp. range||-70° C to 380° C (Lepton2.0/3.0 only)||-20° C to 250° C|
|Spot sensor temp. accuracy||0.5° C over wide range||±2 ° C or ±2%|
|Temp. measurement mode||every position, multiple positions||spot (center) mode|
|Image modes||IR image, visual image, combined||IR image, visual image. MSX|
|Color schemes||18 different color schemes||rainbow, iron, grayscale|
|Storage mode||picture and video||picture only|
|Storage capacity||8 GB internal storage||500 sets of images|
|File format||standard BMP and raw data||standard JPEG and raw data|
|Operation time||about 4-6 hours||about 4 hours|
More thermal images in full resolution can be found here.
THERMAL IMAGE COMPARISON
This is a comparison between the DIY-Thermocam, the Seek XR and a FLIR E8 thermal imager.
The standalone PC thermal live viewer software allows you to capture HQ thermal and visual images, as well as videos right on the computer. Various settings can be changed over the UI, including a calibration and two different transfer modes. The software is written in Python, so it can be modified to your own needs and executed on any OS. New firmware updates can be flashed to the device easily with the firmware updater application.
There is a powerful thermal analysis software for the PC, called ThermoVision. The image browser can show all thermal & visual images on the internal storage, when the device is connected over USB. They can then be loaded with one click. The software allows you to analyze and edit the thermal raw data files right from the device, create combined images and stream & record live images (thermal & visual) from the Thermocam. You can even set temperature thresholds, which trigger a specific action like opening a file, saving an image or sending a command to the serial port.
The second possibility to view and edit the raw data files right on the PC, is the thermal data viewer. It allows various functions to alter the thermal range, add measurement points as well as various filters. The program is also capable of converting whole folders of raw data frames into images (JPG, BMP or PNG) or avi videos. The live tab allows you to stream live images from the device and the calibration tab offers functions to edit the raw-to-absolution temperature conversion. You can also convert videos or interval pictures with the video converter to avi videos.
VIDEO OUTPUT MODULE
If you want to mount the DIY-Thermocam on a drone or just wanna output the video signal to a TV screen, consider adding the external video out module to your device.
It just needs to be plugged into the microUSB cable of the Thermocam and is also supplied with power by the internal battery.
It is capable of providing a HDMI signal or analog video output (PAL & NTSC) with a resolution of 640x480 pixel.
You need the following parts:
|Raspberry Pi Zero||ThePiHut.com|
|Sandisk 8GB microSD||Ebay.com|
|Mini HDMI adapter||Ebay.com|
|2-pin female header||Digikey.com|
Download and flash the complete image to the SD card, it runs a python script that you can modify to your own needs.
Check out the video output module manual how to assemble and use the module.