Lesson F1.2: Distance and Wait Until

The distance sensor estimates how far the nearest visible surface is from the sensor. A wait-until approach keeps moving while the reading is above a threshold, then stops close to the object.

This is a stopping rule, so it needs a safe limit. A sensor can miss a narrow, angled, transparent, or low object. Telemark limits the search distance; a physical program should also include a maximum travel or time.

Official hardware activity

Complete Training Camp 2: Playing with Objects.

Simulator practice

Turn toward the loose object or target, then use a distance stop. Compare a 5 cm threshold with a 20 cm threshold.

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Try it in the SPIKE App

Approach a broad wall at low speed. Add a second stopping condition based on motor rotation or elapsed time so a missing reading cannot run the robot forever.

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