MacGyver Season 2 Episode 8 Science Notes: Packing Peanuts + Fire

Fooling a Motion Sensor

MacGyver and Jack use a large blanket to hold up in front of them in as they move slowly down a hallway. The idea is to trick the motion sensor so that they can steal something.

There are several different types of motion sensors. If you have one in your house for your security system, it’s probably a PIR-Passive InfraRed sensor. This basically works by detecting the infrared radiation that your body emits because of its temperature. For this type, you can just block the IR light coming from your body-at least in theory.

Other types include a microwave sensor. This emits microwave light that reflects off things. If the thing is moving, there will be a slight shift in the reflected frequency-it is this change in frequency that tells the sensor something is moving. Yes, this is the Doppler Effect.

But could the sheet method actually work? Yup. This was tested by the MythBusters.

Hanging boot to fool painting sensor

They need a painting off the wall. It has a sensor that detects if the painting is lifted up. MacGyver hangs a boot on the sensor to mimic the weight of the painting.