19. mBot2 Won't Do Line-Following

This guide applies to:

mBot2 and mBot Neo.


Routine Check

Refer to the quick steps below to rule out basic issues.



In a Nutshell

When your device won't perform line-following as expected.

It's usually due to Quad RGB Sensor. Do the following steps.

  #1 Calibrate the Quad RGB Sensor.

  #2 Check if the Sensor is Faulty.



#1 Calibrate the Quad RGB Sensor

This is to make sure the sensor is adapted to your environment.

Factors like light condition and ground color will affect its performance.

Calibrate every time when you change to a new environment is recommended.


During steps 4~5 mentioned above, please check:

  If the indicators turn solid on white background, the calibration is OK.

  If the indicators keep flashing, please do the calibration again.



#2 Check if the Sensor is Faulty

Move mBot2 to cross a line back and forth by hand and observe.

The indicators should stay solid in the background and turn off on the line.

If not, the sensor is likely to be faulty. Please contact customer support.



#3 Check the Line Following Function

1. Press Home Button on the left side.

Tap Switch Program, and press Button B
Push the joystick to the left to enter the programming interface.
Move down the joystick and select "mBot2_demo2".

image - 2023-09-15T181932.663.png

DSC12 (1).jpg

2. Check if mBot2 follows the line properly.

If yes, the sensor may need to be calibrated again, or the line following program may be faulty and need to be improved according to the example program in mblock v5.4.0 app as shown in the photo below.
image - 2023-09-15T182136.457.png

image - 2023-09-15T182208.408.png

If not, the quad RGB sensor is faulty. Please contact service@makeblock.com for further advice.


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