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

You are right, in a sense. These sensors do need moving components. However, they are a chip on your board. Tiltsensors (actually, accelerometers), and gyroscopes (and pressuresensors, ...) are part ...
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17 votes

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

The sensory device is a weight on a spring. It is indeed "small-scale motion of some tiny components of the sensor", and it's also "another chip on a circuit board". The key word here is MEMS. It's ...
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15 votes
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Identify this component with a weight inside a cylinder

It looks like a vibration motor. A small electric motor with an unbalanced weight on the end of the shaft. Apply a small voltage and it should spin and vibrate. Looks a lot like this one.
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10 votes

What sensor should I use to determine if my project is moving?

If it's for use on a bicycle then I'd use a low-power opto detection circuit on the spokes of the wheel. There are several variants of this and of importance is the ability to pulse the LED to ...
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10 votes

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

Theoretically, yes, a phone or tablet could work just as well in say the International Space Station (ISS) as it does here on the ground. Let's break this down a bit. There are two types of motion ...
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10 votes

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

All the comments and answers are great to help you understand how it is possible. But, here's something that will help you understand how it's actualized in real products. (image source) This is a ...
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8 votes

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

This is a rare case on the Electronics site where, none of the answers clearly and crisply answered the question! Do cellphones retain the ability to detect tilt in zero-gravity conditions? The ...
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8 votes

A few questions on PIRs and other motion detectors

PIR sensors have quite a few advantages: they’re very cheap they use very little power (since they’re passive) – very important for battery powered/wireless sensors. We’re talking microwatts here. ...
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7 votes

What sensor should I use to determine if my project is moving?

An accelerometer would be suitable in most cases. Technically acceleration will be 0 at a constant speed, but in practice unless your project is mounted on some sort of exceptionally low vibration ...
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  • 1,066
7 votes

Can I electronically trigger a PIR motion sensor?

You may be able to cause it to trigger if you place two filament bulbs operated under-voltage at a dim glow in front of it, you may have to tune the positioning a bit to get it right. Then switch ...
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7 votes

What sensor should I use to determine if my project is moving?

While you specify 'seeing if it's moving' as your goal. I might recommend a different measure of checking if the bike is in motion. The amount of noise accelerometers capture is astonishing - it could ...
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7 votes
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Can failure of an old electrolytic capacitor be precipitated by motion?

It's very unlikely that an electrolytic capacitor failed as result of being moved. They generally either degrade gradually as the electrolyte dries out (greatly accelerated by high temperature) or ...
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5 votes

How are microcontrollers designed?

An experienced engineer could hack this together in an FPGA fairly quickly using a hard or soft core for the micro. A good design would take longer because of documentation, CDRs and other parts of a ...
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5 votes

What sensor should I use to determine if my project is moving?

Accelerometers as others have suggested are pretty easy to use especially on an Arduino with all the libraries and breakout boards available. Another thing that might worth looking at is a Piezo ...
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5 votes
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Faster PIR Sensor speeds?

The BISS0001 is a not well documented (In English) Chinese IC. How it operates with certain changes is not well known. But the changes you made shouldn't affect it's life. In the posted schematic, ...
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5 votes
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PIR sensor not triggering P2N2222

Your problem is that the transistor is on the high side, and you're only giving it 3.3V on the base. Since your base-emitter junction must have approximately 600mV across it in order for current to ...
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5 votes
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Read Quadrature encoders over I2C bus

However, I don't have a microcontroller on the remote PCB. So put one there! It is exactly for this type of application where tiny micro controllers are great. There are lots of 8 pin chips which are ...
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4 votes
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Robotics Experts: How to do trajectory planning for a robotic arm

One "quick" solution (not necessarily that quick, but quicker and more robust than starting from scratch) is to use something like Blender to generate position information for a configuration you want ...
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4 votes

What sensor should I use to determine if my project is moving?

Some kind of a low-resolution high speed camera and optics that takes many photos (at hundreds or thousands of frames per second) of the surface it is moving on, and compares them in real time with a ...
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4 votes

Read Quadrature encoders over I2C bus

The common mistake is to assume quadrature decoding needs some form of edge detection and counting the edges. It doesn't. You simply need to sample both states twice as often as an edge may occur. → ...
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3 votes
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Low power reliable motion state sensor for car

As you have hinted in your question, an accelerometer with a 30 second poll interval would probably be the lowest power solution. Tilt switches and piezoelectric sensors aren't going to be sensitive ...
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3 votes

Calling a routine every x miliseconds

Pseudo code: ...
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3 votes
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Understanding use of accelerometers to measure angular (rotational?) accelerataion

Let me guess the location of the accelerometer. My goal is to measure the instantaneous acceleration of the rod while its moving. I will assume it's on the extremity of the rod. There would be 2 ...
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3 votes

Can I electronically trigger a PIR motion sensor?

A small quantity of warm but not boiling water will often trigger a PIR (safety in mind) or on a cold day just tap water - just throw it into the air near the sensor. Alternatively a few drops of cold ...
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3 votes
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A motion sensor that can be covered?

I'd say you are missing the concept of remote temperature sensing versus direct contact temperature sensing. They are not just working with temperature (as in body heat) but with infrared radiation (...
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3 votes
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How to detect end of avaliable movement of mechanism connected to a stepper motor, without external detectors?

Stepper motors seldom use encoders. As you suspect, they normally run a homing routine, reset a counter to zero and keep track of the steps from then on. If you stall the mechanism the controller ...
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3 votes

A few questions on PIRs and other motion detectors

Motion sensing is pretty broad. Doppler radar can detect motion. Anything that detects changes in light will also detect motion (which is pretty much just the same concept as a PIR sensor but using ...
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3 votes

A few questions on PIRs and other motion detectors

Motion sensing can be done with cameras. OpenV and other technologies can detect motion from image section analysis over time instead of heat changes over sensor sections. This is unlikely to be ...
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