Before this, we built a simplermotion detector circuitthat turned on an LED once motion was detected. But 1 or 2 seconds after, the LED would go off. The difference between that circuit and this one which we're now building is that an alarm must stay on once it is activated until it ...
The glass is then opaque to the infrared energy these heated things are emitting, so the heat is trapped inside the greenhouse. It makes sense that a motion detector sensitive to infrared energy cannot see through glass windows. There are a variety of motion detection sensors, each with unique...
The most common glass-breakage detector is a simple microphone connected to the brain. Microphones measure variations in air pressure fluctuation and convert this pattern into a fluctuating electrical current. Breaking glass has its own distinctive sound frequency (pattern of air-pressure fluctuations)....
In a CSI van, you might see hack saws, pliers, a pipe wrench, a pry bar, wire cutters, bolt cutters, shovels, sifters, a slim jim, a pocket knife, measuring tapes, orange marker flags, a flashlight, batteries, chalk, forceps, Vise-Grips, a compass, a magnet, a metal detector, di...
Before we take a look inside a speedometer, it will be helpful to review how a car works in the first place. The basic process is described below: Piston engines use energy from a burning fuel-air mixture to move a piston up and down in a cylinder. This reciprocating motion of the pis...
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Rotary encoders are used to measure the rotational motion of a shaft. Figure 1 shows the fundamental components of a rotary encoder, which consists of a light-emitting diode (LED), a disk, and a light detector on the opposite side of the disk. The disk, which is mounted on the ...
Electric Bike Hub Motor—How to Replace a Hall-effect Sensor: Jeremy Nash explains what a Hall-effect sensor does in a brushless motor—and how to replace the sensor when it fails.VideosHow to make a magnet polarity detection circuit: Thomas Kim shows us how to make a magnet detector based...
When it comes to home safety, smoke detectors play an important role in warning you and your loved ones of immediate danger. That’s why it’s vital to not only provide regular maintenance but also keep in mind when it’s time to replace your smoke detector. Not doing this risks the ov...
Experimenting with Really Good’s js motion detector. I wanted to keep this proof-of-concept very simple, so I ripped out a code and features I did not need for basic motion detection from this demo. Next step was to hook this into a remote feed instead of a local one. ...