Sensors Definition and 153 Threads

Hi, I would like to understand the reason for the "Black sun" effect that occurs in CMOS cameras (very bright spots appear as dark). Thanks, ALex

Hey everyone, I'm a student working on building a wind tunnel with some classmates. I'm in charge of figuring out the drag and lift force sensors. I'm currently looking these two components: http://www.jameco.com/webapp/wcs/stores/servlet/Product_10001_10001_2128260_-1...

Hi evryone. My name is Lucian, I'm a Computer Engineer. I'm working in a project of a company to develop a flow meter using a microcontroller and Infrared sensors. I'm stuck in the mechanic fluid part. We're trying to develop this product basing in the mechanic model of the attached picture...

Hey everyone - I am looking for individuals with thorough knowledge of force and/or pressure sensing technology (specifically piezo and/or QTC). I am a designer/inventor with a problem for which I am ill-equipped to solve on my own and could use some guidance. Please reply if you are well-versed...

I am working on a system that uses capacitance sensor probes, the system components are the probe, triaxial cable with LEMO connectors, BNC cable, oscillator, and a demodulator. I have had some trouble finding ways to troubleshoot the system other then basically testing continuity. Are there any...

Hi folks, I'm playing around with capacitive sensors (mutual capacitance sensors) and interested in computing/approximating the capacitance between the sensor lines. Mutual capacitance sensors usually consist of two lines/conductors that intersect. Obviously, one can model this is a parallel...

Hi :) I'm designing a research and need you guys's help :) It's an experiment to finding out what happens in our brain when we are stimulated by electricity. I have to collect the signals from brain, but not using EEG. (I already failed once...:'( ) I've been thinking about MEG, but it...

Hi :) I'm designing a research and need you guys's help :) It's an experiment to finding out what happens in our brain when we are stimulated by electricity. I have to collect the signals from brain, but not using EEG. (I already failed once...:'( ) I've been thinking about MEG, but it...

Hello there! I'm working for about 2 months to build a system for getting digitally values about the angle of the elbow. The project is designated to create a large usage tool and that's why it's preferably to use mechanical staff that are comfortable for the 'user' and to not look very...

Dear All, I am not sure if this is the right place or not for this post so i apologise in advance if not. I am trying to find some pressure sensors / transducers to measure the pressure difference (with respect to static pressure) at points on a circular cylinder model installed inside a...

Hello Forum, Why are infrared (thermal) cameras, those that produce interesting thermographs of objects, mapping their surface temperature, so expensive? IR sensors are ubiquitous and very inexpensive...What is the difference? thanks, fog37

hello! is there a degree that studies the interaction between radiation, light, ultrasound, electromagnetic waves, etc with matter? in particular to develop sensors that detect chemical substances thanks!

I would like some assistance to select the right sensor/transducer to monitor current from an inverter to the spindle motor it feeds. If it is possible to get RPM signals from the inverter please advice on how to go about it. Please suggest the most suitable sensor/s to achieve both current and...

There is a graph of voltage gain against frequency...but it seems like for a gain of 1, that the gain increases after a certain voltage... I know that that doesn't make sense and there is something I don't understand. I have attached a doc with the image from the datasheet in it. How do I...

Hello ! This is my first post on the Physics Forums. I am electronics technician employed in mass spectrometry laboratory at RBI Institute, Zagreb, Croatia. My question is related to calibration of RTD sensors, which I must do in another lab or division, and since I developed prototype of...

How do you get started learning how to write a program to display and manipulate information from various sensors? What I am mainly interested in are volts and mA's since that's what most transducers and sensors use. I would like to be able to see the information on a computer or eventually on...

Hello All, i am working on an HHO dry-cell project for which i need to decide upon the sensors to be used in monitoring the process parameters. 1. some sensor for monitoring and displaying the electrolyte level in the bubbler during experiment. 2. some sensor for monitoring the...

I understand the basic gist of the whole DC brushless motor, but I don't understand why there needs to be a sensor. Why can't the controller just alternate between phases at a constant rate? What I mean is that if there are a fixed number of ways the coils can be charged, why not just alternate...

I've been looking all over and it appears like I may be using the wrong words to really get a solid answer. I figured I would ask here and maybe someone could either give me a few better terms to help my search or would know the answer already. Thanks in advance! I'm working with a team...

I am not sure if this is the right place or not for this post so i apologise in advance if not. I am trying to find some small pressure sensors that can go inside a seat cushion or something and that can be connected somehow to a computer system to indicate when they might have been triggered...

My task is: I need to build a very thin scale (like a bathroom scale), less than 8mm in thickness total, and needs to work even if placed on rough terrain (so it needs it's own bottom and top). The total load will not exceed 10kg. I've been trying to look for the correct force sensors to use...

Hi, I am trying to create a hall effect based position sensor to be attached onto a DC motor to generate feedback for position control. I am thinking of the following arrangement: 4 hall sensors are placed 90 degrees apart around the magnetic element. Each sensor surface is directed at the...

Hi Reading another post about the inverse square law by trewsx7 on this forum, I had the idea that maybe the gravity field isn't constant at some parts. Imaging a 2-dimensional gravity field produced by a source. Considering ∏, there might be a repeating infinitesimal patterns on ∏ where...

Hi, Can anyone please tell me how does crash impact sensors work in an airbag system? Like, I want to know at what force does the sensors send the signals to the airbag control unit. And can these sensors be incorporated to the rear bumper as well? I am planning to incorporate this sensor for...

Hello science folks! I've just started learning about trilateration. I am wondering if its possible to calculate the coordinates of a continuously growing circle(for example a sound wave) which hits three sensors at different times. I have added a picture so you can see what I mean. In the...

Hi all, I have been looking the electrical symbols for a proximity sensor and a level sensor. A simple google search has not helped and I have also looked at various manufacturers websites, but still no joy. I was hoping somebody could point me in the right direction to a comprehensive list of...

Has anyone worked with piezoelectric materials before? Currently starting research work with them and totally new to these materials... I'm currently looking to buy CHEAP *non-toxic* piezoelectric PVDF and ceramics. Goodfellow seems to have PVDF, but paradoxically the website says it's a toxic...

Hello everyone here at the physics forum. Forgive me if I am not posting this question in the correct forum. I am not a physicist, but I do know my way around a little bit. Now on to my question. I am a security consultant who conducts security audits and specializes more specifically in...

Hello, A project I am working on currently requires me to test how capacitors in our circuit react to change in Humidity. As expected, the experimental results suggest that capacitance goes up with increasing humidity, as the electric permitivitty of air surrounding capacitor increases...

Since it is impossible to get certain cleaning solutions (in Canada, at least) like "Eclipse" (methanol) and pure isopropyl alcohol (from drug stores) is adulterated with some kind of greasy oils that leave smear marks behind, I would appreciate some help as to what chemical solutions might be...

Dear Experts I come across a website showing specifications of a PIR motion sensor for toilets. I quote the specs : Type 180° Motion Sensor Application Toilet, WC, Bathrooms, Restroom, Cloakroom Technology Wall mount Passive Infrared PIR motion sensor Reach 10 meters Time...

I'm really curious as to how it's possible for image sensors to capture scenes that look so accurate. The tiny color filters placed over the photosites are dye-based and due to that and their thinness I assume this means that a green filter must let in quite a bit of red and blue light which...

Hello, I'm working on an invention in which I'm trying to build a prototype for. I have very little physics background and nothing in computers which is why I've sought help here. The project seems very basic, but I have no idea where to start. I need help hooking up two hygrometers...

Hello..I'm a undergrad student from hyderabad ,India. Presently I'm am doing a theory based research project on fiber optic current sensors ..which are mainly used to sense current in substations . Recently i got a paper when i googled on the net. It was titled Temperature and Vibration...

Hello seniors..im a undergrad student from hyderabad ,India. Presently I am am doing a theory based research project on fiber optic current sensors ..which are mainly used to sense current in substations . Recently i got a paper when i googled on the net. It was titled Temperature and...

I have a bunch of photodiodes and I want to interface to these to a computer using my sound card. I have 12 sensors and stereo input samples at around 96000hz. My idea is to connect 12 sensors to each line and have them turn on or off at a specified offset so that the total output signal would...

I placed this in quantum department but since no comments came either it belongs here or is too trivial. Please comment. MY POST IN QUANTUM PH. FORUM ... " This problem I encountered in my photography forum. A new model of camera comes out with a much higher megapixel sensor (Nikon D800...

This problem I encountered in my photography forum. A new model of camera comes out with a much higher megapixel sensor (Nikon D800, 36mpix). I argue that such sensor will need new lenses to be meaningful. Others claim that a given lens performance (here resolution) is always utilized by a new...

I would like to determine the equation describing the trajectory of an object using data from 2 distance sensors. I figured out how to do this if the sensors take simultaneous measurements but this cannot be done without generating crass talk between the sensors. The object moves too far when...

Homework Statement Suppose you have two sensors with rates of noise R_{A}^{noise} and R_{B}^{noise}. Suppose an erroneous signal occurs if the two sensors have a noise trigger within time \tau of each other. Show that the rate of false signals is R_{AB}^{noise}=2R_{A}^{noise}R_{B}^{noise}\tau...

Hello everyone, as the title suggests I'm in need of finding some specific vendors or catalogs for a few particular items needed in my design project. My University will be taking care of the bill, so while I would appreciate modest cost expenses, it would benefit my college to have some of...

Hi all. I have a couple questions for those familiar with mechatronic stuff. I'm looking for some type of [(angle sensor) + (axle) + (Perhaps a slip ring as well)] all in one. The slip ring is necessarily going to be in the final project that I'm using it for but I could get a slip ring...

Hi there, I need a help. There're given 4 sensors (any kind of sensor which can transmit&receive signals in order to find a distance between another sensors around there). And we know the position of first sensor, say x1=0, y1=0, and have to find other 3 sensor's position. We can easily find...

hello can someone suggest a simple fiber optic pressure/temperature sensor that can be constructed ...with reasonable accuracy and less equipment... i came across a few papers about the same...but not sure about the scale and precision required... please help thanks

Hello, for my robot project, I'm using a system of of sonar range finding sensors which are generally used for this type of thing. My question is of there polarity. I'm assuming that it does not matter, for there are no clear indicators of positive or negative values on any of the poles. here...

I am doing a module to adjust the noise in a motor such that motor inside piston stroke is touching some mechanical part leads to small noise. I would like to adjust these by using sound sensoror presser or vibration sensors. I don't know which one to use in that sistuation but my guess is sound...

I have been working on a small project involving temperature measurement in a geothermal installation. I am using constant current sensors (AD592) that will be placed about 100 feet down the holes. I have the circuit designed and the PCB drawn up but I haven't printed it yet. I want to ask...

Was looking for a cool project concept involving a remote helicopter and I decided on trying to triangulate its location and maybe make it autonomous. Started doing the math and realized i was really looking to trilateralize its location using the magnitude of 3 distance sensors set in a...

This is a complete newbie type question as I am certainly not an electrical engineer. Are there such things as microchips or RFID's that detect moisture? I'm thinking of things like sweat in humans. Does anyone have any ideas? Thanks, I appreciate any comments

Hi I'm taking part in a robotics contest and that requires my robot to reach the desired destination using line tracking. The line to be tracked is made of white tape. Now I'm in a sort of dilemma here. I was in favour of using IR sensors to track my line and through experimentation I...