Questions tagged [sensors]
Use this tag for questions about selecting, connecting, using, and debugging sensors.
1,246
questions
48
votes
17
answers
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How to trigger an alarm when toilet paper is low?
Anyone with kids knows they never help with the toilet paper. Anyone know how to track when it's low or out and sound an audible alarm? I just don't know what sensor to use that may help.
Some that ...
22
votes
12
answers
26k
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What type of connector does the GROVE system use?
What type of connector does GROVE use?
I'm interested in wiring some old sensors so they're compatible with GROVE, so I first need to identify the connector so I can buy the housing and pins to crimp....
18
votes
4
answers
29k
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How to get weight data from glass electronic bathroom scale sensors?
I am doing a small project with a bathroom scale but I run into some problems. I am using an Arduino Uno V3, HX711 module amp and a scale.
Scale:
HX711 amplifier:
I disassembled the scale to get ...
16
votes
2
answers
45k
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The use of 4.7kOhm resistor with DS18B20 temperature sensor [closed]
I was using a temperature sensor DS18B20 with Arduino.
I've read that you should connect the digital input line and the 5V line with a 4.7kOhm resistor - like in the picture.
Can someone explain ...
16
votes
1
answer
10k
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How can I sense when someone is sleeping with my Arduino?
Ignore the stalker-like title.
I am thinking about creating a project with Arduino that can sense you sleep habits, when you're asleep, and how much you sleep. It would be convenient to not have to ...
14
votes
10
answers
18k
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Sensor for underground water tank level
In a similar way to the question "best way to determine if a 5 gallon water jug is getting empty", I'm looking for a way to measure water in a container. This is so it can be connected to an Arduino ...
13
votes
5
answers
29k
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My DS18B20 is reading high. How can I get it to return the correct temperature?
I am working on a heating control system for my home, but having problems with the temperature sensor reading higher than I expect.
I have a 5V Arduino Mini Pro clone hooked up to a relay module, an ...
11
votes
4
answers
288
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How do I know if a board fits my requirements?
I'm new to Arduino and I saw on their website that there are many different kinds of boards.
What are the differences, or to be more specific, how would I know which board meets my requirements? I ...
10
votes
4
answers
2k
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How do you handle sensor drift?
I have a pair of potentiometers, on the Arduino, the output seems to drift, by one or 2 digits, back and forth. I would prefer they were read as one fixed value, without variation when their knobs are ...
10
votes
4
answers
6k
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How to move from arduino to physical prototype
I've been reading a bit about moving from Arduino to PCB and it seems a bit daunting. For now, all I really want to do is take something I've built, and make a few changes so that I can actually ...
10
votes
4
answers
42k
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What is the work of pulseIn?
I have code for an ultrasonic sensor which I found from a site. Here is the code:
#define trigPin 12
#define echoPin 13
void setup() {
Serial.begin (9600);
pinMode(trigPin, OUTPUT);
pinMode(...
10
votes
1
answer
12k
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Emulating 1-wire device(s)
What I want to do is make a ATTiny IC become a slave on the 1-wire bus, with its own S/N and command list for its specific functions.
What I want to know is if I can use the one wire library from ...
9
votes
9
answers
7k
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Best way to determine if a 5 gallon water jug is getting empty
I have an espresso machine that gets its water from one of those 5 gallon blue water bottles (I would plumb it, but our water here is WAAAAY too hard).
If I ever accidentally let the bottle run out ...
9
votes
2
answers
18k
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How can I sense very high temperatures with Arduino?
I've seen many temperature sensors, but the highest temperature they go up to is 125 degrees C (257 degrees F). I want to reach higher temperatures than that. I'm thinking about rigging up a closed ...
9
votes
3
answers
15k
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Grove sensors without a Grove shield
There exists a large variety of sensors in the Grove System. Usually these are accessed via a special shield (Grove base shield).
Can I access these sensor directly without a shield. In particular I ...
9
votes
2
answers
8k
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Reading a varying voltage into Arduino
Using an Arduino Nano and a current transformer (CT), I'm trying to sense the current flowing through a 120 V 60 Hz line.
Circuit
CT outputs 0-1 V according to its specifications....
9
votes
3
answers
3k
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How to measure total energy usage of an arduino board
I have a project that I'm currently working on. We have built a green wall, wich consists of plants on a wall
Now, we have a pump situated at the bottom that waters all the plants. There is an ...
8
votes
2
answers
4k
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Why analogue pins affect each other?
I have a sensor and it generates an analogue signal.
I am reading all analogue data and sending it to my computer.
uint8_t sensors[] = { A0,A1,A2,A3,A4,A5,A6 };
const int len = sizeof(sensors) / ...
8
votes
1
answer
2k
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What good designs are available for Geiger counters using an Arduino?
Are there any good circuit designs for Geiger-counter projects using an Arduino?
If so, what Geiger-Muller tubes should I choose to detect different types of radiation?
8
votes
3
answers
2k
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Using more than one Ping Ultrasonic Range Finder
I have done various applications with the Ultrasonic example project but it is always using one pinger. I'd like to make a scanner resting on a servo sweep but to reduce sweep time use more than one ...
7
votes
3
answers
19k
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Multiple I2C sensors with the same address
I am trying to find the simplest way to connect multiple (preferably around 10-20) IMU sensors to one controller. There are two constraints: sampling at 60Hz and reasonably simple wiring as I want to ...
7
votes
1
answer
4k
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Why does increasing resistance make a capacitive sensor more sensitive?
From the Capacitive Sensor Page on the Arduino website, it states the following:
The capacitiveSensor method toggles a microcontroller send pin to a new state and then waits for the receive pin to ...
7
votes
1
answer
7k
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Pressure transducer / sensor (0.5 - 4.5V) innacurate analog pin readings
I have a relatively cheap 0-15psi pressure transducer. It has 3 pins - ground 5V and signal. The signal outputs a voltage of 0.5V to 4.5V based on pressure from 0psi to 15psi. I can verify it does ...
6
votes
9
answers
6k
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Lock screen if I leave my seat?
Background: I change the job and in the new company you need to pay pizza for the whole team if you forget to lock your screen :-)
I want it to be automated: I walk away and the screen should lock. ...
6
votes
2
answers
615
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Why is that any sensor signal need to be hooked up to the interrupt pins on Andruino boards?
I have come across some Andruino Sensors like Motion, Light and all recommend to be connected to pin 2 or 3 on Andruino Uno board which are interrupt pins. This is especially true if you are looking ...
6
votes
2
answers
15k
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How to choose between AM230x and DHT22 temperature and humidity sensors?
I'm looking forward to getting an accurate humidity and temperature sensor.
Right when I decided to go with a DHT22 module, I saw AM230x (AM2301, for example).
How do I choose between DHT22 and ...
6
votes
3
answers
7k
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Binary serial transmission order of data
I'm implementing a filter for my IMU Sensor and thus I want close to real time data visualized on the computer. I use binary serial communication to facilitate the sending part for the arduino (as far ...
6
votes
5
answers
3k
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CO2 sensor for arduino
I want to add CO2 measuring feature to my room weather station. Can someone please recommend a CO2 sensor easy to integrate with Arduino?
6
votes
3
answers
2k
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Serial sensors and the Yun
I am involved in a project that is going to measure PH and chlorine in a swimming pool. The plan is to use a Arduino Yun. The sensors we are going to use are connected using serial. Since we may be ...
6
votes
2
answers
7k
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Oil Pressure / Water Pressure / Boost Pressure ( Turbo Engine )
I'm an automotive enthusiast and I want to build some gauges by myself using Arduino.
I was taking a look at this pressure transducer or sender, 100 psi, stainless steel, for oil, fuel, air, water ...
6
votes
2
answers
438
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Why sensor acts erratically?
I am trying to connect an ADXL355 digital sensor to an Arduino. The wiring and the code I think are OK because the system returns the correct values sometimes and partly correct answers mostly. The ...
6
votes
1
answer
8k
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Compute yaw from magnetometer and accelerometer
I use an Arduino and a 9 DOF sensor (gyroscope, accelerometer and magnetometer) and I'm trying to use the pitch, roll and yaw that the sensor gives me to rotate an object in unity.
I managed to ...
6
votes
2
answers
753
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Why is my TMP35 giving me weird values?
A TMP35/36/37 is giving very high voltage readings, which results in high temperature readings. The serial monitor looks like this:
As you can see, the sensor value is in the 900s, voltage is almost ...
6
votes
2
answers
2k
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Calibrating Accelerometer Sensor
I'm working with an Adafruit LSM303DLHC Accelerometer Sensor hooked up to an Arduino. I've downloaded the appropriate libraries to make it work and uploaded the example sketch "accelsensor.pde". I ...
6
votes
1
answer
1k
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A good water flow meter to monitor home usage with Arduino
I'm searching for a good water flow meter to add to my home controller project with Arduino. I have been searching in several pages and I only found some devices that work for low flow. I need to ...
6
votes
1
answer
3k
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Level tracking using optical or capacitance sensors
I am looking to devise a level tracking system using arduino and some sensors. My particular situation is I have solute that is coming out of solution and I want to track the formation rate of the ...
5
votes
4
answers
703
views
Briefly "wake up" Arduino in response to an event
I want to connect a device to a door handle, so whenever someone opens the door I'll be able to send a message via my arduino that is connected to a WIFI shield.
I have a simple orientation sensor, ...
5
votes
2
answers
8k
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Pre-heat time required for MQ-5 gas sensor
The datasheet of MQ5 sensor says, it requires a pre-heat of 24 hours. Does this mean that it needs to be powered on for 24 hours consecutively before usage? Some other websites (e.g. http://www....
5
votes
4
answers
21k
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How to connect more than 10 sensors to Arduino uno r3
How I can connect more than 10 sensors to Arduino Uno R3? I calculated it and I can connect just 4 fire flame sensors (sensors which can find a fire (a candle, for example)) and maybe 1 ultrasonic ...
5
votes
2
answers
19k
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What is the difference between Accelerometer, Gyro, and Magnetometer Sensor?
I'm starting in the arduino world and I'm building an autonomous smart vehicle.
So, after some weeks building and adjusting the vehicle, I got to a point in this project that I want to log it's ...
5
votes
3
answers
6k
views
Return value of 0 if value is less than zero
Background: I am using an analog pressure sensor with a range from 0-100PSI returning voltage values .44v to 4.44v. It's open air (or 0 PSI) voltage on the signal pin is .47 volts. I have a function ...
5
votes
8
answers
13k
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Two sensors on one input
I got this question from my teacher the other day and I can't figure it out:
If you have two sensors from two different outputs but want them to go into one input, what do you need, and how can you ...
5
votes
5
answers
6k
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How can I make a garage door laser sensor?
I would like to make a sensor that detects when my car is clear of a certain point. So, when backing in my car to my garage, I would have a beam and sensor. When the beam is broken, an LED light would ...
5
votes
4
answers
4k
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Issue with HC-SR505 sensor
I have been using a HC-SR501 PIR module with my Arduino Mega and it was tracking presence pretty well.
Because of cost constraints, I decided to go with HC-SR505 sensor - bought a bunch of them. The ...
5
votes
6
answers
10k
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Using / calibrating pH sensor module
I've bought this sensor module board to link to an Arduino nano: http://www.ebay.com/itm/For-Arduino-Liquid-PH-Value-Detection-detect-Sensor-Module-Monitoring-Controller/321764233326
I assumed the ...
5
votes
3
answers
7k
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Humidity values returned by DHT22 sensors failing after some time
I've built a weather station using Arduino that measures temperature/humidity and pressure using an Adafruit 8266 HUZZAH. Temperature and Humidity are measured using a DHT22 sensor a ordered from ...
5
votes
4
answers
3k
views
Running multiple tasks at once
For a school project we're working on a wearable device to track people's movement and heart rate. We use an Arduino Pro Mini with a heartbeat sensor and an accelerometer. The wearable device uses ...
5
votes
1
answer
2k
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Strange values from LSM303 Magnetometer
I am having problems with values i get from Pololu MinIMU-9 boards's magnetometer. I am using Arduino-micro and the arduino library from Pololu. The sensor on the board is 3 axis accelero- and ...
5
votes
3
answers
4k
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Arduino Due and BNO055 address in i2c mode
I have a project where I need to have several IMUs, the BNO055 shuttle board (I explained my project here), I manage to get the Euler angles from one BNO055 sensor, which have the address 0x29, ...
5
votes
2
answers
2k
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Stacking Arduino Shield (Motor Shield, LCD Keypad, LED Sensor)
I'm building a line follower with arduino, here some part that I'm going to use
Arduino Uno
Motor Shield 2A http://www.dfrobot.com/index.php?route=product/product&product_id=69
LCD Keypad
4 ...