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Module 2 · Line Tracking

Lesson 1 · The Reflectance Sensor — Knowledge Checks

Name Date

  1. Your sensor reads 0.8. What is it most likely over?

    1. A.A white surface
    2. B.A black line
    3. C.The edge of the line
    4. D.Nothing — that value is impossible

    Answer Why?

  2. Your 'off line' (white) values average 0.2 and your 'on line' (black) values average 0.8. What threshold should you choose?

    1. A.0.2
    2. B.0.5
    3. C.0.8
    4. D.1.0

    Answer Why?

  3. Why does the XRP have two reflectance sensors instead of one?

    1. A.As a spare in case one breaks
    2. B.So it can tell which side of the line it is on
    3. C.To read the line twice as fast
    4. D.One reads white, the other reads black

    Answer Why?