I just put together my first mBot. We will be using these in a classroom setting. The obstacle sensor mode using the onboard button works fine, but the line sensing mode doesn’t. The bot just goes in a straight line. I saw somewhere that there should be two blue lights on the sensor if it is reading reflectivity, but I only have one. Does that mean something is wrong?
mBot line sensor not working out of box?
XW_makeblock
#2
Hi, jlwinsett
When the mBot works properly with Manual mode and Wall avoidance mode but doesn’t work with Line follower mode. There are following reasons which may lead to the issue for line follower mode:
a. The default program may not function properly in mBot, please upgrade firmware for the mBot and then reset default program have a try. Refer to steps in FAQ 1 How to Upgrade Firmware for mBot 1. How to Upgrade Firmware for mBot.docx.zip (690.6 KB)
and FAQ 2 How to reset default program manually 2.How to reset default program manually.docx.zip (677.9 KB)
.
b. If you use the IR remote controller to control the mBot, you need press the button C to enter the Line follower mode.
c. The Me Line Follower sensor may not connect to the correct RJ25 port. Please connect the Line follower sensor to the Port 2 on mCore board.
d. The wire connection may loose or the RJ25 cable between the line follower module to mCore may faulty. Please replug the RJ25 cable for both side or change a RJ25 cable have a check.
e. Low battery. Please change the battery have a check.
According to our test and research, it is suggested to use rechargeable Li-ion battery or rechargeable nickel-metal hydride, nickel-cadmium which can be bought from amazon or local shop. Or Alkaline battery with good quality like Energizer, DURACELL.
f. If the line follower mode still doesn’t work while the other modes works properly after tried above, the line follower module may be defective.
To double confirm this, you can test with the following program. If the value from the panda changes when you move the mBot from black to white (or white to block) area, that means the Me line follower module is ok. If it always says 0, it should be defective.
You must upgrade firmware for the mBot again to clear the memory before you test the following program.
Hope the above troubleshooting steps help you.
Best,
XW