Are they detecting heat? Or are they detecting something else? Is there a way to move so discreetly that a motion sensor wouldn’t detect your movements?
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One of the most common motion sensors is PIR (passive infared). These are those sensors you see with a white plastic dome or visor strip for automatic lights and security systems. That white plastic acts as a lens. It focuses infrared light onto a sensor. That sensor has a lot of different sections. Its waiting to sense a rapid change in temp across 2 or more of those sections. It only looks for rapid changes to avoid a false alarm from an environmental temp change.
This leads to a few different methods of not tripping them.
One is called “slothing”. Its just moving extremely slow, like a sloth. The intent is to spread the temp changes you create on the sensor over longer time periods so the sensor treats them like background temp change. This technique works, but is a lot harder than you’d think. People are not very good at moving extremely slow for long time periods.
Another is shielding. A large piece of glass (glass is opaque in IR) or something ambient temperature is held up between you and the sensor. You can move faster this way, but anything peaking around the shield will trigger the alarm.
You can also stay in the “shadows”. This means you pretend the sensor is a flood light and you only move in the spots behind objects that would create a shadow. Basically figuring a path that keeps you out of sight of the sensor.
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