water level with ultrasonic distance meter - error readings
Posted: 25 Apr 2019, 15:41
Hello everybody,
Im pretty new with ESP easy, in the past i have done few projects with arduino, now I wanted to test out D1 mini with ESP8266 since I want to do project over wifi and its pretty simple with ESP Easy. I dont have a vast knowledge on this topic, so I may have done some mistakes Im not aware of. I will start with quite general question with minimum details to keep it simple.
I have a water tank on my yard and I wanted to check water level in this tank with ultrasonic sensor. My setup is:
Solar panel -> battery charger -> 18650 battery -> step up to 5V -> D1 mini -> ultrasonic distance sensor
Everything is going smooth on non-liquid surfaces. I can get a precise reading +-0,5cm over 3 meters. But when I direct the sensor at the water surface it works correctly only up to 80cm. So the readings are 70cm = 70cm, 80cm = 80cm, 81cm = 51cm. This error is not linelar (like 20% error from measured distance or something) but this error is ALWAYS 25-30cm (when the sensor is 180 cm away from surface, the readings are steady on 150-151cm).
I have even tried out to pour water into a large bowl (I filed it to the top so there is no readings from the sides of the bowl) and the error was the same like in the tank.
Can anybody help me why this is occuring?
I have tried several distance sensors (JSN-SR04T, HC-SR04, HY-SRF05) but all of them are measuring the same errors. And yes, I can easily correct this issue with function in node-red but I would like to find root cause since I cannot trust those measurements.
Im using this D1 mini:
https://www.amazon.co.uk/Makerfire-Node ... B071S8MWTY
Thank you for your help in Advance!
Barashur
Im pretty new with ESP easy, in the past i have done few projects with arduino, now I wanted to test out D1 mini with ESP8266 since I want to do project over wifi and its pretty simple with ESP Easy. I dont have a vast knowledge on this topic, so I may have done some mistakes Im not aware of. I will start with quite general question with minimum details to keep it simple.
I have a water tank on my yard and I wanted to check water level in this tank with ultrasonic sensor. My setup is:
Solar panel -> battery charger -> 18650 battery -> step up to 5V -> D1 mini -> ultrasonic distance sensor
Everything is going smooth on non-liquid surfaces. I can get a precise reading +-0,5cm over 3 meters. But when I direct the sensor at the water surface it works correctly only up to 80cm. So the readings are 70cm = 70cm, 80cm = 80cm, 81cm = 51cm. This error is not linelar (like 20% error from measured distance or something) but this error is ALWAYS 25-30cm (when the sensor is 180 cm away from surface, the readings are steady on 150-151cm).
I have even tried out to pour water into a large bowl (I filed it to the top so there is no readings from the sides of the bowl) and the error was the same like in the tank.
Can anybody help me why this is occuring?
I have tried several distance sensors (JSN-SR04T, HC-SR04, HY-SRF05) but all of them are measuring the same errors. And yes, I can easily correct this issue with function in node-red but I would like to find root cause since I cannot trust those measurements.
Im using this D1 mini:
https://www.amazon.co.uk/Makerfire-Node ... B071S8MWTY
Thank you for your help in Advance!
Barashur