Likely a very silly question, but I’ve developed a robot that uses the SEN-13582 Line Follower Array to follow a black tape line (specifically gaffer tape) on a light background. The end user is in a different location, so I tested the robot at my location and got it to reliably follow the line before shipping it off to the end user’s location.
The problem is that the end user has not been able to reliably calibrate the sensor array. We’ve tried following the calibration steps from the hookup guide several times but can never get it to track reliably.
More specifically, the system is designed to use “intersections” (i.e. perpendicular tape strips across the main line that act as waypoints) to navigate. However, false positive readings for those intersections are common, which we defined as sensorBar.getDensity() > 5
i.e. 6+ sensors “lit” at once (since we’re using sensorBar.clearInvertBits()
). This is a problem that I never experienced more than once during initial testing at on my test track using the exact same tape.
I know that the sensor is supposed to be recalibrated to account for different ambient conditions. At the destination, the “track” that the robot is trying to follow is a 3/4-inch-wide strip of the gaffer tape laid over a section of smooth concrete that has been painted with glossy white spray paint, while the original testing took place on a lightly-polished hardwood floor. Both settings are indoors, with similarly bright and steady interior light.
My question, then: is it likely that the glossiness of the spray paint is the reason why we can’t reliably dial in the line follower array? Or is there some other obvious culprit that I’m overlooking?
Also, any tips for calibrating PID steering using this sensor are welcome. The robot in question has a much wider wheelbase than most line follower robots (> 20 in. / 51 cm wide between the drive motors), and so far this has meant that the robot jerks very strongly in response to the stepwise changes in error value every time the tape line passes from one sensor to another.