One of the main goals of my project is to measure the water level using the ultrasonic sensor. So, I was trying to measure the water level using the TDK Demo Kit. I used a 25-liter water jar and positioned the sensor unit at the top opening of the jar. After launching the demo kit software, I activated the sensor’s zero calibration. With this setup, the sensor measured a distance of 235 cm. I was a bit confused about the reading because the actual height of an empty jar should be more.
I filled one-third of the jar and measured the distance again. Surprisingly, I got the same reading from the sensor, which is shown in the following image.
I filled the jar to about half and still read the same value. I became very disappointed.
I continued the experiment and filled the jar to about two-thirds of its capacity, but the measured value remained unchanged.
I was quite disappointed with the reading, yet at the same time, curious to understand the reason behind it. I suspected that the narrow neck of the jar might be causing the inaccurate measurement. To eliminate this issue, I decided to use a water bucket instead of the jar. The bucket has a wide opening, which should prevent any obstruction or disturbance to the sensor readings. I made the following setup to measure the water level of the bucket using the sensor kit.
With a portion filled, I was getting the following result (not 235cm at this time!). The reading was around 165cm.
I added more water to the bucket until it was nearly full, and the sensor reading changed as expected. This confirmed that the previous error was for the narrow neck of the jar.
Since I plan to measure the water level in a large tank that doesn’t have a narrow opening, the sensor is unlikely to face any difficulties or produce errors in level detection. I got a very accurate level in the case of the water bucket.
