Hello, and welcome, this fast tutorial is about the PAJ7620 hand gestures sensor, it permits your hand gestures to be detected by the Arduino board, and then you can use it to control lights, robots (cool stuff), HMI, games… using IR LED and optical CMOS array, it can detect up to 15 gestures.
This one costs around $2-3 only but is not efficient (as you can see in the video) as the thermal imaging arrays that can much detect complex gestures cost around $30-40.
The gestures that can be detected are: right, left, up, down, forward, backward, clockwise, counter-lockwise and waving. Those are the basic 9 then you can add right-left, left-right, up-down, down-up, forward-backward, backward-forward. (Check the video to know the differences).
There are two ways of detecting:
- Near, which is on 5-15 cm distance with 60° angle
- Far, on 15-30 cm distance with 30° angle
For this project I’m going to interface it with Arduino Uno board, and I’ll use a LCD i²c screen to show the gesture detected, using this method you can adapt it to whatever project you’re working on.
The tests are straight forward, just plug and start moving your hands.
Overall the module performances are not bad for $2, sometimes it can be tricky when detecting the Forward gesture, you can check the code to actually find that it can be confused with other gestures, you can always modify the detection speed for all and for the forward and backward alone:
Also, make sure the module is on a flat surface, otherwise the clockwise and anti-clockwise gestures won’t be detected. Make sure you have enough space for you hand to move.