TSL262

Feeling our way with sensors

Posted Wed, 19/09/2007 - 16:54 by peteh
The sensors are a critical part of a micromouse. Primus uses six infra-red reflective sensors. Here is code to test that they are working. Now that we have a nice display to show what the sensor reading are, we can get that module tested. Since the hardware is very simple, there is not a lot to go wrong. Yet somehow I had a dead sensor when I first tested the Primus prototype. It was a simple dry joint that would have been detected by more careful inspection of the board.

Sensor test

Posted Wed, 01/08/2007 - 17:14 by peteh
The simple sensor circuit described by Ng Beng Kiat seems to give the best results. On his web site (http://www.np.edu.sg/alpha/nbk/) Beng Kiat describes Min4, one of his recent mice. In there is a PDF with schematics for the mouse. The sensor circuit for Primus is essentially the same except for a couple of component value changes. The emitters are run in series pairs from the 5V supply.