Case in Point Load Cell

The locus taken by the roots of the characteristic differential equation of the load cell as the applied mass changes can be determined by automatic system identification techniques. Such a locus is illustrated in Fig. 7.5, and the roots of the compensating filter need to follow it. For each value of mass there is a corresponding final output of the compensating filter once oscillation has ceased. The trick is to make the parameters of the filter vary with its own output as dictated by the locus. 

When a load is first applied, the compensating filter is set to the parameters for zero load and as the signal begins to rise the parameters follow it. As the output signal crosses the correct value the compensating filter is exactly 

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