About the influence of temperature and humidity in the values. about arduino-mq131-driver

[ostaquet]

The temperature and humidity influence has been designed based on data sheet details on page 4.

The formulas have been designed based on the sensitivity curves.

[ostaquet]

Additional comment on this, @nitram147 fixed some bugs in the calculation of the environmental correction. Please use the v1.4.0 to have the last version.

[ferreiradiego]

Hello @nitram147. Could You explain to me why the value of resistance is divided by the value of getEnvCorrectRatio()? As in the line code correctedValueR0 = _valueR0 / getEnvCorrectRatio();. My doubt is about how the resistance ratio is corrected, is the code to correct the ratio only a mathematical artifice?

PS.: I'm doing a study about MQ Sensors and the more details I get, the better will be my study.

[ostaquet]

The idea is to compare apples with apples. ;-)

According to the data sheet, the resistance of the sensor is affected by the temperature and humidity. This impact is implemented with the corrective ratio coming from getEnvCorrectRatio().

But... this should be in the calibrate() function and not in the setR0().

[ostaquet]

It is quite a good question...

At the moment, the correctedValueR0 is defined when the setR0() function is called. According to me, it is not exactly correct.

The R0 should be adjusted when we calibrate the sensor and when we get the R0 value (because the R0 value evolved with the environment).

[ostaquet]

I dig a bit deeper in this and there was an error in the code uploaded before. Sorry about this.

If we look carefully to the data sheet, we can see that the environmental corrective ratio has to be applied on the Rs/R0 ratio and not on the measurements of the resistances.

It is fixed in v1.4.1.