Hello everyone
I am Engineering student, I want to use MPX4250DP pressure sensor as a depth controller for my underwater glider. This is differential pressure. I have arduino UNO and want to use pressure sensor for a depth of 2.5 m. My requirements for pressure sensor is that, It may give me readings after each 3 cm depth. I am new in this forum and didnt use pressure sensors before.
So my questions about this sensor are:
Can I use it for my requirements so that I get values of depth of the glider after each 3cm depth ?
How can I use this ?
Thank you
Barkat_utp:
Hello everyone
I am Engineering student, I want to use MPX4250DP pressure sensor as a depth controller for my underwater glider. This is differential pressure. I have arduino UNO and want to use pressure sensor for a depth of 2.5 m. My requirements for pressure sensor is that, It may give me readings after each 3 cm depth. I am new in this forum and didnt use pressure sensors before.
So my questions about this sensor are:
Can I use it for my requirements so that I get values of depth of the glider after each 3cm depth ?
How can I use this ?
Thank you
No,
This sensor outputs 18.8mV/kPa. 3cm of water is about 0.302kPa ~ 0.1kPa per cm, and the ADC on the arduino is only 10bit. With a 5V reference that equates to 4.88mV per bit each if the ADC was perfect your position would be +- 3cm . the entire range of 0 to 2.5 m would be 0.472V or about 97 counts.
If a value between 0 and 97 +- 2 would work for your depth, maybe you could use it.
I think you would want a more sensitive ADC, a 16 or 24bit device. The pressure sensor should work, but you will need a better analog to digital converter than the builtin one in the Arduino Processor.
Chuck.
What will be the reference pressure for your relative pressure sensor? (it's said to measure absolute pressure as well)
Is that gas pressure sensor usable with liquids (water) as well?
How do you want to compensate the pressure offset resulting from the moving glider, waves etc.?
IMO you should do some practical research on underwater pressure measuring, with devices mounted to your glider, and in the intended environment (salty/fresh water?), with and without motion. What types and levels of interferences will occur?
With the integrated 1.1V ADC reference you can gain an factor of 5 vs. the 5V reference, but I'd suggest an amplifier that cuts off the zero-depth offset and spreads the intended range into the full ADC range. Then you can obtain 2.5m/1024 (~2.5mm) per ADC step, so that the built-in ADC will be sufficient. Most important is an algorithm to filter out all interferences, so that you can obtain reliable (stable undisturbed) readings.