I am planning part of a project where I want to extract espresso and measure the rate of change of the extracted fluid. This extraction doesn’t occur at a single rate, instead it starts very slowly and progressively increases. My project will hopefully measure the rate of change of mass at multiple points of the extraction, as well as the overall mass at those points in time, and based on those measurements make suggestions to the user with regards to grind and dose change.
My question is whether the HX711 load cell amplifier has some sort of lag that would negatively impact such a measurement, or whether such a measurement is even possible. Is there perhaps a different chip I should look at for this task?
I am planning part of a project where I want to extract espresso and measure the rate of change of the extracted fluid. This extraction doesn’t occur at a single rate, instead it starts very slowly and progressively increases. My project will hopefully measure the rate of change of mass at multiple points of the extraction, as well as the overall mass at those points in time, and based on those measurements make suggestions to the user with regards to grind and dose change.
My question is whether the HX711 load cell amplifier has some sort of lag that would negatively impact such a measurement, or whether such a measurement is even possible. Is there perhaps a different chip I should look at for this task?
So basically you want to measure how quickly a cup of coffee fills up? Or how? Or what size of mass? I don’t understand what sort of flow you want to measure or control. Dissolved particle density? Fluid pressure probably factors in somewhere. … And no, it’s late in the day, I already had my startup coffee this morning.
Either way, the amplifier is basically an ADC with serial data output. So yeah, lag and low data rates are inherrent. It’s in the datasheet. Too much? Test it in a trial. Your application is too niche for (m)any here to be able to give a sensible opinion, I think.
What I’m trying to do is measure both the total extracted mass of espresso over a period of ~25 seconds (that’s the most important one, at least at this point in time), as well as the rate of change of the extracted beverage mass (which is more to see if I can see patterns forming between rate of change of beverage mass and good/bad espresso shots).
By measuring the beverage mass with respect to time, I can get a pretty reasonable analog (mass of dry coffee grinds / beverage =extraction ratio), which is measured in TDS when using a refractometer. By using the extraction ratio I can avoid having to use a refractometer for every single espresso shot, as that would quickly become tiresome.
By measuring mass of coffee grinds vs extracted beverage mass I also get a way to indirectly measure the fineness of the grind, as I cannot see a way to directly measure it.
