You have a colleague who has used a hall effect sensor in a scale model of an automated car wash. They set a threshold on the response of the sensor to determine when a rotating brush with a small magnet attached had returned to its position after cleaning. The model worked in the prototyping lab, but when they moved to outdoor testing on a clear day, they found that performance degraded by afternoon, then improved again overnight. What do you suggest the problem might be?

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Determining the threshold indoors and the sensor heating in the afternoon sun mean that the sensor isn't responding the same in the afternoon, so the threshold may no longer be appropriate

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Additional environmental stress (breeze, vibrations from traffic) has affected the sensor's shielding and the signal from the sensor is now too noisy for the threshold.

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In the afternoon, the sun shines into the model, and the light affects the response of the sensor to the magnet.

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The metal parts of the brush are heating up in the sun, which alters its magnetic properties and affects the sensor's measurements

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You have a colleague who has used a hall effect sensor in a scale model of an au...

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