We often write a post and then learn something new and cool from the comments. The same thing happened when [Andreas] posted a video about monitoring fluid levels. Commenters told him that the best fluid level sensor was a hacked blood pressure monitor. He didn’t know that, and we didn’t either, until we watched his video, below.

It is well-known that an air-tight tube in a tank that is closed at the top and open inside the tank will develop a pressure that corresponds to the liquid level in the tank. This is a common approach when you want the pressure sensor to be far away from the tank in, say, an enclosed building. So why use a blood pressure monitor? Because a common enhancement to the system is to use a pump to pressurize the measurement tube first so the system can tolerate small leaks. The blood pressure monitor has everything you need: a pump, a valve, and a pressure sensor.

Continue reading “Blood Pressure Cuff Hacked Into Water Level Sensor” →