Questions tagged [sensor]

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Which neutral atom-based quantum sensor is hardest to build/operate?

I am currently going through the presentation, "Sensing with neutral atoms", by Grant Biedermann. I understand that, according to the talk, there are a large number of different sensing ...
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In a light plasma, how many electrons pass through a given area

Assume you have a light plasma of about 10^5 particles per cm^3. The energy-density of the plasma is about 0.1eV (as in near earth orbits, see here: http://assets.press.princeton.edu/chapters/s9500....
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Simulating accelerometer and magnetometer reading on an inclined plane

Suppose that we have a device equipped with a 3D accelerometer and a 3D magnetometer. The device is positioned on a slope so that the slope in the forward direction is $\theta$ and the slope in the ...
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When should smartphone be declared as static using accelerometer reading? [closed]

I wish to know when should I declare an smart phone static by reading its 3 axis accelerometer reading. I have notice that modulo of all 3 axes gives 9.8 when ever smart phone is static. What does it ...
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How can one detect a device (phone) falling using its 3-axis accelerometer?

I am working on an Android app to use its 3-axis inbuilt accelerometer to find if the phone falls. I googled and found that if the following value is less than 2: $$a = \sqrt{x^2 + y^2 + z^2}$$ (where ...
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What does photon-limited imaging mean?

The following link is about Photon-Limited Imaging, https://engineering.purdue.edu/ChanGroup/project_QIS.html. Is there any definition of Photon-Limited Imaging. From the paper Photon-Limited Object ...
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Is it possible to obtain noise level in electrons using only one camera?

In the link, https://www.photonstophotos.net/GeneralTopics/Sensors_&_Raw/Sensor_Analysis_Primer/Photon_Transfer_Curve.htm there is one figured called Standard Photon Transfer Curve – Multiple ISOs ...
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How does a sampling rate of 1ns equate to 15cm for an optical instrument?

I’m currently working with open source data captured by the NASA GEDI LiDAR instrument and I am applying a math model to it. GEDI’s sampling rate is said to be 1 nanosecond or 15 centimeter resolution....
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Is Daredevil's superpower conceptually possible?

The Marvel superhero Daredevil is blind but has heightened senses, enabling him to perceive the world around him to a far greater extent than a regular person. In his depiction in the Netflix live-...
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Principle of operation of a Gyroscope-Free IMU

What is the principle of operation of a Gyroscope-Free IMU, or how can angular accelerations and velocities be measured with accelerometers?
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What is the negative pressure?

I have vacuum pump connected to quartz tube and vacuum sensor, when the pump reaches it max value the sensor reading (-1 bar) and the analog gauge in the pump reach the max value which is (-1000mbar). ...
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Integrating a continuous low sensitivity sensor with a discrete high sensitivity sensor

In inertial sensors specifically rotation sensors there is a current drive to make atom-based gyros, the reason for this is that there is a potential increase in sensitivity. However, currently, atom ...
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What is the intuition behind excluding the effect of gravity from accelerometer data

In the unit of accelerometer and linear acceleration, I see that accelerometer is angular and the linear acceleration is linear. There is the impact of gravity on the accelerometer. However, ...
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How does the world's most accurate accelerometer work?

i'm having trouble finding any sources that describe what the most accurate accelerometer is. I'd like to know what it is and how it works.
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Is there any sensor that creates a visual image of magnetic fields?

I am working on a project where I am trying to create a magnetic tag that can be detected from $20 - 50$ cm away. Is there any sensor on the market capable of this?
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The change of mechanical into electromagnetic waves and vice versa [closed]

I know that sound is a type of mechanical wave, so the human eardrum changes mechanical energy into electronic energy (impulses) so the information may be processed by the brain. Question: As ...
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Compute capacitance of planar interdigital electrodes

My apologies if this is not the right place to post a question like this. I am looking to do post-grad research study next year in the sensory field for sensing gases like hydrogen, nitrogen or ...
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PVDF sensor response time

I am trying to measure the voltage response from a high energy impact using the PVDF sensors. Here is a description of the experiment. I would like to measure the high impact energy on the aluminised ...
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Measuring radio transparency of material in relation to frequency

More specifically, I'm just wondering how I would calculate if my 16 MHz radio wave will go through a specific material (bonus points if there is a handy formula for this). My first thoughts are that ...
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Through-metal-wall Ultrasound sensor imaging?

A while ago, MIT published a paper that used a radar sensor to take a low-res image, and then they trained an AI model to convert the image into a human skeleton for through-wall human pose detection. ...
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Does the size of CCD/CMOS of a telescope affects the magnification?

For a normal, traditional telescope, the magnification level should equal to focal length divided by eyepiece diameter, i.e., $$Res=\frac{f}{D}$$ So does the size of the CCD/CMOS the same as eyepiece ...
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Why do the sensitivities of magnetometers and gravimiters have such strange units?

It looks like the sensitivities of magnetometers and gravimeters are usually reported with the units of $\text{Tesla}/\sqrt{\text{Hz}}$ and $\text{Gal}/\sqrt{\text{Hz}}$, respectively (where "Gal&...
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Does a tuning fork's resonance frequency increase with a repulsive force on it in AFM?

I have a tuning fork sensor with a probe tip that would be used in atomic force microscopy. Am I correct that the quartz tuning fork's resonance frequency increases with a repulsive force on it and ...
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Clarifications on the calibration of a magnetometer?

I've been reading up on magnetometer calibration (sensor fusion in general) recently and got confused about some things. To my understanding, hard iron effects (e.g. inductors and magnets) which are ...
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How is measurement uncertainty defined / calculated (of a sensor or measurement)?

Textbooks and online sources often say the industry standard for uncertainty is given at a confidence interval of 95 %. This means out of 100 measurements, 95 would achieve the specified value and ...
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Is there any way to differentiate UV light from visible or IR light?

I'm working on a small sensor system that responds to only UV light and I wanted to know that is there any way to differentiate between UV light and the rest of the spectrum like using lens if so then ...
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Brightness Temperature layered atmosphere

I'm trying to figure out how to apply the radiative transfer model to calculate the brightness temperature Tb in microwave (Rayleigh–Jeans approximation) considering atmosphere and no scattering. If I ...
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How exactly does a (capacitive) humidity sensor work?

How exactly does a humidity sensor work? For example, how can it differentiate between a relative humidity of 30 % and 35 %? I know how a capacitance works but for me that principle is way too high ...
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What is a piezoelectric sorption detector?

I'd like to know what a piezoelectric sorption detector is. I can hardly find information about, only a small number of research papers which are mostly not accessable for me. Only given from the term ...
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Measuring real time water usage with live water pressure monitoring

My home started seeing high water bills recently. My water company doesn't provide live water meter readings. There is a water meter on the street which I can monitor while water is being used but I ...
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How does a weather station temperature sensor work? (physics behind)

In an automatic weather station, a temperature-measuring electronic sensor (which is typically 1,5 m in the air above a grassy ground and covered from direct sunlight) is in a certain way coupled to ...
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Any method to detect extremely weak electromagnetic wave signal? (10^12Hz, level ~10^(-28) Watt per meter^2 per Hz)

Could you please let me know whether there is any method on the Earth to detect some EXTREMELY weak electromagnetic wave signal, if it is a planar wave, if its exact waveform is completely known (...
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Measure fluid speed by using a hot plate [closed]

I would like to figure out whether it is possible to measure the speed of a fluid by letting it flow across a hot plate. I was thinking about using the formulas for forced convection. The plate is ...
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Accelerometer vs linear acceleration during an impact

I am trying to understand the relation between the accelerometer and linear acceleration during impacts. At work we have an accelerometer and gps onboard sensors installed in a few cars. The ...
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Graph analysis of accelerometer data

I used my mobile accelerometer sensor to collect data from a moving bike where I held it in my hand in a way that the smartphone sensor +Y axis is in the direction of the moving bike always. This can ...
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What does it mean by (±20%) in sensitivity of a pressure sensor?

Sensitivity: (±20%) 15.5 pC/psi (225 pC/bar) this the sensitivity rating of a pressure sensor. what does it mean by (±20%).
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How to measure distance between object and mobile phone using camera? [duplicate]

I am trying to determine the distance between object being photographed and the mobile camera which is capturing the photo. The only device that is used is mobile phone, can we get depth or distance ...
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Total output power of a laser

What is the interpretation of and the difference between the total power and total output power of a pulsed laser? How are these parameters measured and which type of detectors are the most ...
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Slots in optical incremental encoder

How can I calculate the amount of slots I need in my optical incremental encoder 's code wheel? For example, how many slots there should be, if I want to determine the position of screw which is ...
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How LHC sensors work? [closed]

newbie here. I am here because after working with Raspberry Pi sensors and Analog to Digital converters, and computer processors, I wondered how exactly do sensors in large scale physics experiments ...
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Would a speed camera register more speed if it moves in the opposite direction than the object it's measuring?

Earlier today, I was talking with my friend about speed cameras measuring different speeds when moving. This is the situation: I am the red car and I'm driving ...
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Basics of camera calibration

I tried to find some useful explanation about camera calibration and stereo camera setup in the web but was completely overwhelmed by the hairiness of the content: but seriously though, does it have ...
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Why photodiode measures random phase superpositions on continuous-wave (10kHz) white light?

I measured a 10 kHz modulated white light using a photodiode (Thorlabs PDA10A): Unexpectedly, the photodiode output sensitively depends on the orientation and position of the photodiode. For two ...
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Unique optical map of a uniform metal object

Given a metal object (let us say a perfect planner uniform surface) that has been exposed to external environment factors such as sun, wind, rain and others for couple of years. This object has been ...
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Measuring pressure or weight from an uneven weight distributed surface

I am new here so I hope I'm posting it at the correct place. I am having some troubles with some of my force sensors. My case is like this: I have a body which have a weight. However, the surface is ...
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2 votes
1 answer
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Can a syringe be used as a hanging scale if needed?

FYI: This is not a homework q; I am just curious... You can assume that... the syringe tip cap creates a "perfect" seal, i.e., keeps air from flowing in/out! the syringe is completely depressed ...
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Estimate pendulum motion

I have a simple system: a pendulum and two sensors (RADAR which will tell the distance $dx$ and $v_x$ and a Gyroscope, the gyroscope is giving me the information about $\omega$ - angular velocity) as ...
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How to Measure Electric-Field Probe Sensitivity?

I am doing some reading on current methods for detecting electric fields. A figure of merit for the systems is, naturally, the minimum strength of field that can be measured, in units of Volts per ...
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Why does a cooking thermometer show different temperatures when touching the container of a liquid?

I have a cooking thermometer that looks like a 10-15 cm long metal rod, that can be inserted into the thing you want to measure the temperature of: When inserted into boiling water, I observed that ...
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What are the magnitude of voltage fluctuations in field surrounding the human head?

How much would the scale of the electric field caused by neuron activity in the brain vary as it radiated from the scalp? Also what would be the typical noise level over the same space attributable to ...
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