Theo, THErmal Observer, is a my little project about a very cheap thermal scanner with alarm remote capability. Sensor is very strong: an array of thermal pixel, like more expansive thermal camera ones. A servo rotate, continuously over 180 degrees, this thermal sensor and a wide area is covered. this motion can be switched on/off by a simple REST command. It can be useful as blaze recognition or human body temperature identifier (in a room, for example and to prevent illness). This project is based on Arduino Yun Platform!

Theo’s components:
1) Arduino Yun with firmware (Link)
2) Arduino proto shield (Link)
3) Hitec HS-422 (Link)
4) Thermo sensor array Tpa-81 (Link)

Schema and project:

Theo’s core is an Arduino Yun with an Arduino proto shield with some components
used to control servo motor and read data sensor. Connect i2c sensor to SCL on pin 4 SDA on pin 3 (with 4.7k resistors as pullup).
Servo signal is connected to pin 5, directly. Power are all +5v.
C++ Arduino script export REST protocol to remotely communicate with python script (using TK, PIL and OpenCV library).This can show thermo image and give some controls to sensor sweep. Opencv can also permit some elaboration on image (now there is a smart interpolation, only)

“/arduino/temperature/0” get integer matrix with temperature obtained by sweep
“/arduino/servo/0” stop servo sweep
“/arduino/servo/1” activate servo sweep
“/arduino/speed/X” set X ms as delay time between a new sweep angle increment
“/arduino/pos/X” set sensor angle (X=0/180)
“/arduino/mt/X” set X temperature alarm
“/arduino/mail/X” set X mail address

Inside Arduino code there is a sending mail possibility using ssmpt/mutt (installed with “opkg install ssmtp” and “opkg install mutt”) and testing it with with:
echo ‘Alarm Temperature’| mutt -s ‘Temperature Alarm’ — using this ssmtp.conf configuration file with your gmail account

config file is in /root/ as config.ini.
alarm temperature threshold\n
sweep on/off\n
sweep period\n


Arduino code:Download

Python code:Download

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