Cliff detection

Author: Yisong Xu, Si Xu

Let mBot move forward on a white table (or other light color table) and stop it when it gets to the edge of the table surface.

Hardware requirements:



Upload the program to Arduino

Example program download:

Cliff detection.sb2


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Script description
When mBot travels within the surface of the white table (or other light color table), the line-patroling sensor can receive the returned infrared signal and the value is 3 (both Sensor1 and Sensor2 return 1); At the moment that mBot travels to the edge of the table surface, the line-patroling sensor cannot receive the reflected infrared light and the value is 0 (both Sensor1 and Sensor 2 return 0). When the value of the line-patroling sensor is 0, it is deemed to have reached the edge of the table surface and will be stopped. #how to make games on scratch#
Also if you use this program, mBot will stop moving forward when it detects black.


Extended tasks

Task 1 Modify the script to let mBot move back when it detects a cliff.
Task 2 Modify the script and use block to achieve the effects of this example.


Attached – Line-patrolling sensor structure diagram

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