QTR 8RC calibration problem!


I have the QTR 8RC sensor array for line follower and I using QTRRCExample code. Sensors work but dont recognize white or black ground. It produces values by distance and I cant calibrate.

What can I do ?


Can you explain what you mean when you say that the sensors work but do not recognize white or black surfaces? Are you following the instructions in the comments of the QTRRCExample code? The way that example code is written, there is a ten second calibration phase (indicated by the Arduino LED), and while it is calibrating, you should be passing each sensor on the QTR sensor array over the lightest and darkest surfaces you want them to detect. Please note that the optimal sensing distance for that array is 3mm from the surface. Also, the distance of the sensors from the surface will effect how much IR is reflected back, so you should try to keep this distance constant between calibrating and testing. After the calibration, the main loop of the example code is estimating the position of a line under the sensor array, so if you are just placing the array over a black or white surface, with no distinguished line (such as black electrical tape on a white background), it will not be giving useful information.

If you are still having problems, could you give more details about the behavior you are seeing and how you are using it?