Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [motion]

Motion may refer to the motion of objects, like rotation, drop or picking up, for which **motion sensors** are used. Or it may refer to the motion of persons, for which typically **PIR motion detectors** are used.

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What makes smartphones tilt-sensitive? Will they retain this ability in zero-gravity conditions?

Most smartphones are tilt-sensitive, but what device makes this possible? Additionally, how does it (and the sensors associated with it) work? Also, since the working of these sensors seem, almost certainly, based on the presence of an external…
paracetamol
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Can I electronically trigger a PIR motion sensor?

I would like to trigger a PIR sensor using an infrared LED. Is that possible? My goal is to simulate motion in front of the PIR, when there otherwise is none. I tried using a handheld remote control, but that didn't seem to work.
user1574082
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Which sensor to use for detecting nylon string vibration?

I need to detect motion on a nylon (transparent) stringed instrument. When the string is plucked, it would vibrate and I'd like to know what kind of sensor to use in order to detect the action. Maybe a reflective optical sensor (visual detection)…
cenk
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A few questions on PIRs and other motion detectors

I grew up incorrectly believing that motion detectors (as part of burglar alarm systems) were designed to detect movement, when in actual fact it is the movement of a heated (like body heat) object which causes them to trip. I also understand there…
questioner
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What sensor should I use to determine if my project is moving?

I don't care how much it's moving, how fast or in what direction, I just want my Arduino-based project to know if it is moving or not (so I can shut off high-current drain LEDs when my bike is stationary to save my battery.) Do I want an…
Robert Atkins
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Looking for small motion sensor

Are there other options for a small (< 5mm long) low-g motion sensor than accelerometers? I don't need to measure the acceleration picking up my device causes, I just want a 1/0 signal when it happens. Preferably very low power, <10µA would be…
Geert Goeteyn
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Stepper Motor acceleration profiles for short runs

I've done a fair bit of reading on stepper motors and acceleration. I had to wade through a lot of different strategies with a lot of calculations, including one which called for several candles, and "A maiden of virtue pure" Which while…
darrob
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Car security solution - designing the right motion detector

My car gets broken into quite frequently. The car is right outside of our bedroom window. The break ins happen at night, and we never hear them! They must be very sneaky. I would like to design (or find a plug and play solution) for a motion…
Alex Gordon
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Sample Application with LHI 778 PIR Sensor

For a motion detecting application I found a sensor with code LHI 778. If you look at the datasheet in the link, the characteristics of its internal FET transistor is not specified and there is no information about its internal sensor element. There…
Erdem
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Best way of making a trip-wire type device?

I'm wanting to make a type of electronic "trip wire". My basic idea is to have like a laser and basically when the laser is interrupted then it sends some signal to a microprocessor. I'm not tied to a laser but it was the first thing that comes to…
Earlz
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Generating electricity by moving a door

I'm entirely new to electrical engineering. This is for a hardware/software project I have in mind, where I need electricity without having to plug the device into a power source. My intention is to make a bluetooth "controlled" door lock. For that…
Esben Klindt
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Electronically controlled pneumatic lift, or something similar

Need to be able to firmly lift about 110Lbs (~50Kgs) weight, through a distance of upto 12 inches. The weight can be considered to be a flat & square wooden board, hinged to a flat platform, with the lifting action applied to the free end, s.t. the…
bdutta74
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Identify this component with a weight inside a cylinder

This component was pulled from a device that was used to detect movement. When I first saw this part, I thought it was an electrolytic capacitor, but upon closer inspection, I found that if I shake the part, it has a small metal weight in the end…
Jason O
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low voltage motion sensor

I am looking for a motion sensor device that can track person/animal walking by it and record time/date of the event(s). It needs to be able to run on a small battery or two (maybe 2 AA's or a 9 volt). It does not have to have a screen, just an…
Tom
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12v LED Strip Lights controlled by PIR *Want to add LDR to project*

I want to add an LDR (Light Dependent Resistor) to my Motion activated stair lights, then On/Off switch can be removed as well as the single Led (On Indicator Only) from my project (I want the LDR to control the On/Off). This is basically the first…
Ridach
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