I bought the Zumo kit and completed build on Wednesday. This kit build included the reflectance array sensor. Today, I began testing the robot with some of the library examples.
I can run the buzzer and pushbutton examples successfully. And I can run the motor example with the wheels rotating correctly. Further, I can run the sensor calibration and see the 6 sensors notice the difference in contrast of the white border and black main running area via the serial monitor. So far, so good!
Now, I run the border detect program and it does not behave as expected. The robot runs backward not forward as it is setup. And it changes direction every 2-3 inches effectively creating a tiny square it operates within. This occurs whether it is close to the border or in the center of the main running area. In fact, I am not sure it is detecting the border.
Net, I need help in troubleshooting this issue so I can enjoy my Zumo. Some things to note:
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I have painted a white circle as a border on a black surface. I am using 1/4" black foam board and a sharpie white painted line. The line is about 3/4" wide.
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The batteries are fresh.
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I calibrated the reflective sensor on the white border on the black surface. Numbers in the serial monitor range from 0 to 1000 depending on where the sensor is relative to the border. The serial monitor shows 6 columns of data which changes as each sensor goes over the border in the sensor calibration program. There is a 7th. column which I do not understand what its value represents. It seems to vary around 2500.
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As I pick up the Zumo to turn it off, I can see the 2 tracks oscillate in opposite directions about equivalent in time that would move the Zumo the 2-3 inches in one backward direction.
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I have not adjusted the threshold value that the comment in the program says may need to be adjusted. I will try that tomorrow morning by lowering the value in equal amounts. Based on what I read on the forum by someone experiencing a similar behavior with the border detect program, this did not seem to change anything.
Any idea about how to resolve this problem will be appreciated.