Questions tagged [sensor]
Sensors convert a physical quantity (e.g. temperature, pressure) into an electrical signal.
4
votes
2answers
553 views
How do ultrasonic sensors differentiate between transmitted and received signals?
I understand how these ultrasonic sensors work on the basic level: They send out ultrasound, which is then reflected by an object and is then sensed by the receiver.
But the receiver and the ...
-2
votes
0answers
30 views
Sound interrupt at specified sound level [on hold]
How can I wake my system (interrupt) with a specified sound level?
For example, I set a 10dBm sound level threshold and put my MCU into sleep mode. When the sound level is over 10dBm, I want to wake ...
7
votes
9answers
2k views
What linear sensor for a keyboard? [on hold]
I'm trying to make a velocity-sensitive keyboard for playing music.
I have to measure the position of each key in order to know how loud the sound should be.
The volume of the sound is a function of ...
-1
votes
1answer
30 views
How can i use HTU21D-F sensor with SC16IS750 breakout board?
i have a HTU21D-F humidity and temperature sensor. I want to take data from this sensor on I2C and transformed to UART with SC16IS750 breakout board. And i want to see this signal on an oscilloscope. ...
-1
votes
0answers
23 views
Read internal temperature sensor value from raw register address [closed]
I'm trying to read the internal temperature sensor in a stm32f2 microcrontoller, in our project we are using libopencm3 and using this you should make an adc setup ...
0
votes
0answers
28 views
my LM35 temperature sensor gives weird measurements, [migrated]
Board: esp32
I know my wiring is correct because I get data from the sensor, but the data is a bit weird.
At 22 celcius I get 140, even though if I do the voltage calculation (* 0.473372) it still ...
2
votes
2answers
72 views
Light sensors sensitive enough to detect for PWM from CF and LEDs?
I have an extreme sensitivity to PWM light sources such as computer screens and light bulbs. This can make it very challenging to make a purchase as I end up having to do lots of guesswork with ...
0
votes
1answer
53 views
Ideas to detect when someone is trying to detach an object firmly attached? [closed]
I'm designing a tracker for assets. I want your suggestions to implement into the circuit a method to detect when someone is trying to remove the tracker. I was thinking of surrounding the board with ...
0
votes
0answers
43 views
Capacitance measurement, mpr121 touch sensing keyboard
I have been assigned a project where I have to use interface an MPR121 capacitive touch sensing controller with a microcontroller. Aside from the touch detection, one of the requests for the project ...
-1
votes
0answers
43 views
PT100 temperature sensor
Can a probe type PT100 rtd temperature sensor measure the surface temperature of a container being heated accurately? The PT100 is positioned with one side touching the container. The readings ...
-2
votes
2answers
105 views
How would I go about converting a change in capacitance into frequency? [closed]
I have to make a model for a pressure sensor. The sensor measures the pressure by changing the capacitance. I only have the datasheet for that.
Summary: pressure>> diaphragm deflection >> change in ...
0
votes
0answers
28 views
Resettable persistence sensor
I need somehow to manage pallet movement in one of factory sections. Since my controller can't work with interruption from I/O I need to get I/O reading cycle. But for this reason I need my ...
1
vote
0answers
29 views
HX711 Load cell providing constant large and negative reading
I'm currently working on a project that uses the HX711 load cell amplifier while connected to a series of strain gauges in a full bridge circuit. I'm using an Arduino Nano and have the CLK of the ...
0
votes
1answer
27 views
Sensor signal out logging
I am trying to reverse engineer a pressure sensor thats connected to an ECM and outputs pressure ratings in bars.
i want to tap into the sensor with arduino and create my own voltage --> bars data.
...
0
votes
2answers
60 views
Polarity of Ultrasonic Sensor
I see some ultrasonic sensors have legs with different length, such as below. Does it means they have polarity?
Are there any differences taking different leg as the signal pin?
0
votes
1answer
46 views
Linear actuator. Monitor end switch with arduino
For a hobby project I am developing a solar tracker. For this I obtained a linear actuator. It contains a DC motor, 2 Hall sensors and an end switch. I am using an Arduino Uno and a Polulu motor ...
-1
votes
0answers
36 views
AC/DC Power Supply for Micro Nano reading Flow Sensor Via ADC
I'm using a NANO board with a ATMEGA328p to translate a linear voltage output from a flow sensor.
Its a very simple implementation that reads the ADC pin and creates a calculated pulse signal on ...
0
votes
2answers
76 views
Waterproofing products
does anyone know of a product that can be used for waterproofing electronics and exposed wireing that is suitable for submersion for potentially long periods?
More specifically I am looking for a way ...
1
vote
1answer
49 views
PIR Sensor for bulb in room
This has been very long since I left electronics but recently I restarted taking interest in it as hobby.
I bought some PIR sensors from Aliexpress and found it is very simple to implement if I have ...
1
vote
1answer
42 views
Acoustic Emission Sensor
I wanted to use Acoustic Emission for the detection of termites. I was going through some research paper and they suggested that it can be done using an acoustic emission transducer of 60khz frequency....
1
vote
4answers
145 views
Using enameled copper wire as a capacitor for measuring water level in a tank?
I'm trying to make a capacitive water level sensor using two enameled copper wires used in transformers. I've used sanitary silicone to insulate the bottoms of the wires. (Coating is insulated by ...
0
votes
0answers
15 views
EC Sensor (Analysing the Circuit)
I'm doing an electrical conductivity sensor; my goal is to build a water monitoring device.
After analysis I decided to build my own circuit and make some improvements to other designs.
An EC sensor ...
0
votes
2answers
84 views
How does an ultrasonic distance sensor work?
How does an ultrasonic distance sensor work?
My thoughts:
A microcontroller (Arduino nano) sends a signal to an amplifier that makes it into a 40kHz pulse, which then goes to the transmitter which ...
0
votes
1answer
55 views
Amplifing the output of a current transformer sensor [closed]
I have to make a current transformer sensor from scratch for one of my projects this semester. I bought a torroid ferrite core and wrapped a copper wire around it. Plan was to thread a wire as the ...
0
votes
1answer
29 views
Thermoelectric Cooler sensor
My team and I are testing our Peltier Thermo-Electric Cooler Module+Heatsink Assembly - 12V 5A from Adafruit. We are using an external power source and sensors to get readings for the current, voltage,...
0
votes
2answers
77 views
Analog sensor nonlinearity near the rails
I am looking into a 0-5V analog sensor. The problem with this sensor is that it
will typically swing within 15 millivolts of the power supply rails with no output load.
(datasheet p. 4)
This ...
0
votes
1answer
37 views
RTD circuit in industerial application
I'm trying to design RTD measuring for industrial use which has EMI/EMC/ESD.
I have 3 wires input to the board.
obviously 3 wires out of the board are going to 3-wire configuration PT1000
1- 3V3 (...
1
vote
3answers
86 views
Sensor For Continuous Water Level Measurement
I am designing water level controller for water tank and want to show the water level in LED bar Graph
I know how to transmit data to MCU and show level to LED bar graph but my problem is to find ...
0
votes
1answer
35 views
ibeo lidar 4L setup
I am having difficulties in finding information regarding ibeo lidar sensor power connection.
Lidar has 3 inputs/outputs one is Ethernet, CAN and power terminal.
As CAN only needs 4 pins (high out, ...
0
votes
1answer
39 views
Problem with Bluetooth read range for arduino project
I have been working on an Arduino project for a door entry system in my business office but have encountered a problem.
I have a group of 8 working in my office but we have a room which only 3 ...
0
votes
2answers
37 views
Hall sensor graph
Anyone can help me to interpret the Supply Voltage vs Temperature from this datasheet ? What does it mean ? Why the supply voltage modifies ?
0
votes
2answers
52 views
What type of pressure or weight sensors are thin? (Arduino or R-Pi) [closed]
I want to know if a person is in a walking path of approx. 10x1,5 meters.
I thought on putting thin tables in the path and putting these sensors under each even table (to save some money): https://...
1
vote
0answers
46 views
Does potentiometer accuracy change with degree of movement?
I want to use a conductive plastic potentiometer for my actuator application where movement is +/- 40 degrees.
As in datasheet, the potentiometer linearity is given as +/-0.2 % which I think is for ...
0
votes
0answers
26 views
Choosing a position sensor (encoder) and obtaining velocity from it
How do I know how many counts per revolution I need for an encoder for my application?
I need to be able to accurately capture a 1000 Hz signal on an input side running from 1-133 rev/sec (60-8000 ...
1
vote
5answers
88 views
Summarising from a group of sensors
I have a group of sensors the nominally output 2.5V but if they come in contact with a magnet they'll increase slightly or decrease slightly based on the polarity (north/south pole).
These sensors ...
0
votes
1answer
37 views
Thermopile output voltage range
I'm working with the Amphenol ZTP-101T thermopile to get IR temperature measurements and I'm confused since the thermopile voltage seems to range between -1 and 5 mV at ambient temperature of 25C (...
0
votes
3answers
85 views
Which type of sensor for measuring height of horse step?
Is that possible? I'd like to track the amplitude of a horse leg/foot height for a show.
The many many difficulties:
constantly moving! So ultrasound way too slow
the floor is irregular, made of ...
0
votes
3answers
82 views
Multiple Vibration sensors via single optocoupler
I am designing simple security system to protect 20-30 windows (total length about 50m) with vibration sensors (based on SW-420 modules). Window are on the roof and due to environment i use ...
5
votes
1answer
676 views
Why there are two diodes instead of one used for an LM35 negative temperature circuit?
See the system examples of the LM35 temperature sensor datasheet on page 16, see picture.
This should be used for negative temperatures. However, the voltage change is 10 mV/C and it supports -55 C ...
2
votes
1answer
80 views
Output of LM35 temperature sensor > 3.3 V?
According to the datasheet the maximum rating of the output of an LM35 is 6 V.
However, the output should give 10 mV/C and it supports upto 150 C, which results in 10 mV/C * 150 C = 1500 mV which is ...
1
vote
1answer
93 views
Problem in temperature transmitter because of VFD (Variable Frequency Drive)
I made an amplifier of PT100 bridge which operates on 24V DC supply and gives 0 - 10V DC for 0 - 400°C when tuned. The circuit is as follows :
Here P2 + and P4 S+ are shorted and P4 S- is left open....
1
vote
0answers
37 views
Water level measurement using Optical Mouse Sensor
I wonder if anyone has hacked an Optical Mouse sensor to measure water level in an overhead water tank? Its possible to read frames data from the sensor and if those frames could be processed with a ...
0
votes
2answers
77 views
How accurate are flex sensors?
So for the project I am working on I plan on measuring very precise changes in angle, possibly up to 5 degrees of accuracy.
Are polymer ink sensors (the classic Nintendo power glove flex sensor) the ...
0
votes
1answer
70 views
Using Multiple MLX90614 Sensors on Arduino Board
I've been trying to get something working for a project, getting 4 (just trying to get at least 2 working for the moment) MLX90614 IR sensors connected up to an Arduino UNO board.
I've followed the ...
0
votes
1answer
124 views
Can you connect multiple photodiodes in parallel and treat it as one?
Im working on an IR sensor based off of the Texas Instr. particle sensor (TIDA-00378). They use just one photodiode in their design. I would like to use multiple photodiodes, lined up with multiple ...
4
votes
1answer
129 views
Help Identifying a CMOS optical mouse sensor?
I'm working to repurpose the trackball assembly of a Logitech Trackman wired mouse for use in an experimental rig. I assumed that Logitech would use Avago's ADNS series of optical flow sensors, but it ...
0
votes
2answers
77 views
DS18B20 temperature sensor with Attiny25
I would like to make a simple thermal switch with attiny25 but first I need to read the temperature values from the ds18b20 sensor. I found some codes, here are the sources:
DS18B20 lib
UART lib
I ...
0
votes
0answers
122 views
Water level sensor for a coffee machine boiler
I made a simple water level sensor with an Arduino. A digital pin supplies 5V to a probe in a coffee machine boiler. Boiler chassis is connected to AC ground (earth) and the ground to an analog IO ...
0
votes
2answers
47 views
RTD temperature measurement system resistance question
I am trying to produce a bridge circuit for the following temperature measurement system:
Designed to measure temperatures between 0 C and 100 C with a high accuracy.
When supplied with a 10 V ...
3
votes
1answer
90 views
Switching relay on and off affects analog sensor output voltage
I am working on an AVR project that involves measuring tempereture with an analog sensor (TMP36) and switching a heater on and off through relay to keep the temperature at desired level.
However, I'...
