Imprecision and measuring delays with HX711 and 50kg load cells

Hi, I'm working with a team and we reached a small problem with our load cell. We use a HX711 amplifier connected to 4 Strain Gauge 50kg Load Cells as described in this tutorial https://www.instructables.com/id/Arduino-Bathroom-Scale-With-50-Kg-Load-Cells-and-H/

We can successfully measure stuff, but after some time of waiting for the values to "settle down" and a lot of taring.

We face another problem that after we measure something and remove it from the scale, we get some imprecision in the system, so we need to tare again.

For our final problem we use this for very fast spikes of force applied to it (around 0.75 seconds to go up to 250N and back down to 0N usually). Initially our problem was that the amplifier could only run at 10Hz, but after reading the datasheet we managed to make it work at 80Hz. But now we face the issue that the scale can't measure precisely these "spikes of force" we need since apparently it needs some time to read these variations of force. When we plot the graph it doesn't show the 250N spike, but a much smaller spike.

Here's the code we use

#include "HX711.h"
 
HX711 scale;
 
float calibration_factor = -24050;
float units;
 
void setup() {
  Serial.begin(9600);
 
  scale.begin(5, 6);
  scale.set_scale();
  scale.tare();
}
 
void loop() {
  scale.set_scale(calibration_factor);
 
  units = scale.get_units(), 10;
  Serial.println(units);
 
  if(Serial.available()){
    char temp = Serial.read():
    if(temp == 't') scale.tare();
  }
}

Is there something wrong we are doing? Do we need a better sensor/amplifier? If so, which one would you reccomend?

Thanks a lot!

Sounds like you need a higher bandwidth instrumentation amp and to sample a lot faster. The HX711 is not deisgned for speed at all.

How does the repeatability and precision compare to the datasheet for the loadcell(s) in question?

The loadcell doesn't seem to be the problem from what I researched and the datasheet I found for it.

In the HX711 documentation I just found a "Output settling time" which is 50ms, which sounds like what I'm seeking but I don't really know if that's the "time to fully update a measurement when it changes fast". If that's it, you're right about HX711 not being the right choice for the project.

Anyway, do you know any other option of amplifier I could use that would provide some improvement in this?