Hi. I am trying to make a project with HCSR04 Sensor in unconventional way. What i want is measure the temperature with HCSR04 Ultrasonic Sensor. Ultrasonic Sensor works with sound waves to detect distance measurement. digitalwrite(trig, LOW); delayMicroseconds(2); digitalwrite(trig,HIGH); delayMi…

Welcome to the forum Please post your full sketch

[image] strawhatt: distance = 10; speedOfVoice= (2*distance)/time; This will calculate the speed of sound in units of centimetres per microsecond. [image] strawhatt: temperature = (speedOfSound-0.03314)/0.0000606 What units for speed of sound does this equation require in order to giv…

you get the traveltime in µseconds. Example for a temperature of 18°C speed of sound is 331.5 + 0.6 * 18 = 342,3 m/sec traveltime for a distance of 0.2 m t = 0.2 m / 342.3 m/sec = 584 µsec. 584 µsec is the time that you measure t = t = distance / V(T) = distance / (331.5 m/sec + 0.6 m/ (secK)…

[image] StefanL38: 3_315_000_000 Commas are used in regular writing when dealing with large numbers. There is no need to introduce a new character for that purpose. 3,315,000,000 a7

i will try this code now sorry for late reply. Here is my code. #include <Wire.h> #include <SPI.h> #include <Adafruit_SSD1306.h> ///// #define SDA_PORT PORTC #define SDA_PIN 4 // A4 #define SCL_PORT PORTC #define SCL_PIN 5 // A5 #define I2C_FASTMODE 1 #include <SoftI2CMaster.h> #include "OLED_So…

Used the SRF04 (compatible) with temperature and humidity compensation. There is a table how to compensate for T and H and some links in the repo [image] GitHub - RobTillaart/SRF05: Arduino library for SRF05 distance sensor Arduino library for SRF05 distance sensor …

Thanks but i am trying to measure the temperature with HCSR04 from speed of sound and distance. I am not trying to make pricise the measurement of sensor.

Had some errors in my first posting. Now evyrthing is correct. I did not analyse your calculation. For my my demo-code I calculated speed of sound for 18°C. 342.5 m/sec Then calulated traveltime for 0.2 m 584 µsec And then calculated back to temperature with these values and got 18.28°C (ins…

[image] strawhatt: temperature You can not measure temperature. What you CAN do is measure the speed of sound and interpolate, which travels at a known speed in an environment of known altitude, pressure and temperature. You know the distance from your transmitter to your reflector. As the…

You may need to take many distance measurements and average them to remove random noise from the readings. Even then, on most Arduino, pulseIn() may not be accurate to 1us, I'm not sure. If it is only actuate to, say 4us, then your temp readings will only be accurate to 4~5 degrees C.

Tempreture Measurement with HCSR04 Ultrasonic Sensor

Projects Programming

robtillaart January 10, 2025, 12:27pm 7

Used the SRF04 (compatible) with temperature and humidity compensation.

There is a table how to compensate for T and H and some links in the repo

Topic		Replies	Views
HC-SR04 Temperatura/Humedad Software	8	808	September 11, 2023
Arduino Nano & HC-SR04 Ultrasonic sensor Not working General Guidance	34	337	March 29, 2026
Calculating speed problems Sensors	36	1502	June 11, 2023
Help understanding calibration of HC-SR04 Sensors	45	1535	July 10, 2023
Making an Ultrasonic Anemometer Using Just 2 Ultrassonic Sensors (HC-SR04) General Guidance	141	4319	September 14, 2025

Tempreture Measurement with HCSR04 Ultrasonic Sensor

Related topics