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Measuring pressures have many different applications which require proper encapsulating of the sensors, but at the core there is a limited amount of techniques.

To my understanding, the two leading technologies in high accuracy pressure sensing are:

  1. Measuring resonant frequencies in e.g. quartz crystals
  2. Piezo-electric elements

And there are two leading technologies in pressure transfer from ambient pressure to the pressure sensing element (force collectors)

  1. Diaphragm
  2. Bourdon tube

I found a easy to understand reference to precision and accuracy of pressure sensors Pressure sensor fundamentals: Interpreting accuracy and error. Here they divide Accuracy into the following categories

  1. Nonlinearity
  2. Hysteresis
  3. Nonrepeatability
  4. Zero point error
  5. Span error
  6. Temperature impacts
  7. Long term drift

Most high accuracy sensors promise an accuracy of 0.01% of full scale, but how does this distribute among the different types of errors?

Are there any sensors promising significantly better accuracy?

Is there some technologies that are better than others on e.g. hysteresis or temperature impacts?

Has there been scientific comparisons between different sensors to measure these errors which constitute the total accuracy?

What is the best way of going about to find the sensor best suited for my purpose?

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    $\begingroup$ While I would love to see a thorough answer to this, I think this question needs to be narrowed down a bit. $\endgroup$
    – Rick
    Sep 16, 2015 at 18:36
  • $\begingroup$ I could narrow it down to fit my application, e.g. by specifying a pressure range. I am working on deep subsea pressure measurements. But then others might find the question less interesting. In subsea measurements waves poses such a high level of noise that most don't need accuracy better than 0.01% therefore I was thinking other areas might have more information on high precision pressure measurements. Do you have suggestions on how to narrow it down? $\endgroup$
    – Martin Vatshelle
    Sep 17, 2015 at 13:51
  • $\begingroup$ With an accuracy of 0.01%, surely the problem will not be the sensor, but its implementation $\endgroup$
    – Jodes
    May 4, 2016 at 9:49

2 Answers 2

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The reason sensor error is distributed among all those variables is because different applications have drastically different requirements. Let;s take out the errors you can't do anything about: the non-repeatable errors and hysteresis. They aren't linear or stationary, and as such, it's hard to compensate for them.

There are many sources of non-linear noise, one of which is temperature effects. Those, if you so choose, you could map out the non-linearity in detail and calibrate the sensor to remove much of them.

But ultimately, it comes down you what it is you want to detect. Sensor datasheets will provide a noise density. The larger the measurement bandwidth, the more noise the system will let in. So match the sensing bandwidth to the signal you want to detect. Understand the temperature effect and calibrate/compensate if necessary. That's as general an answer as your original question.

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  • $\begingroup$ MEMS silicon membrane capacitive sensors have virtually no mechanical hysteresis because silicon microstructures exhibit near perfect elasticity, as long as they are not pushed pass their elastic limit. The nice feature of these devices is that they enable one to make a "smart sensor" because the control electronics are incorporated right in the die with the sensing diaphragm. $\endgroup$
    – William Hird
    May 3, 2016 at 2:21
  • $\begingroup$ re: hysteresis -- unfortunately, in order to use the silicon MEMS sensor, it needs mounting, bonding wires, and excitation current. So there is hysteresis from thermal effects, and possibly also from the mechanical behavior of the rest of the assembly, which transmits forces to the silicon, possibly twisting or bending it, which will slightly affect the measured pressure/force. Hysteresis can also be countered (or at least shifted out of the measurement band) with cyclic loading and/or cyclic excitation. $\endgroup$
    – Pete W
    Sep 16, 2021 at 17:35
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Manufacturers tend to hide the total sensor performance and measurement accuracy by dividing the errors in multiple different categories and not adding them up in the end. The best description of error in a pressure measurement I have seen is Total Error Band (TEB). 

Total Error Band (TEB) is a single specification that includes all possible sources of error in a pressure measurement. TEB should not be confused with accuracy, which is actually a component of TEB. TEB is the worst error that the sensor could experience. TEB includes the following (pressure sensors error.png).

One of the most accurate pressure sensor technologies is MEMS capacitive. It can be found both in board mountable and medium isolated versions.

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