Force-displacement-measurement with relative zero point Force-displacement-measurement with relative zero point | HBM

## Introduction

Case A

If a displacement-dependent force F is being checked for compliance with the limit values, an offset of the force from stroke to stroke is disruptive. The force limit values would have to be adjusted for each stroke movement.

# PMX: Force/Displacement Measurement with Relative zero point

The force F and displacement s during a stroke movement are measured. To compensate for random offsets in measurands, new, signals F_tared and s_tared are generated without offset.

Case A

The force is set to zero at point s on the displacement axis: s=s0.

Case B

Force and displacement are set to zero for force F=F0

Two glyphs "Trigger" and "Taring" are used to set the force to zero below point s0. The force curve below s0 has no significance for zeroing.

Case B

To compensate for a displacement offset, the new force zero point should be determined by force F0 rather than by the displacement.

Case A illustrates how the displacement zero point can also be moved. The same condition (F=F0) is used to do this. Both quantities, force and displacement, now have a new zero point.

## Procedure

Case A

A constant signal returns s0, in this case 5 mm:

A Trigger block sets output "Flag01" if the displacement s is in the range between 0 and 5 mm:

Finally the Trigger block sets the raw value of the force F_raw below 5 mm to zero. F_tared is the force value with the offset removed:

Case B

The Trigger block now checks force F against F0

Force and displacement are both set to zero with signal "Flag02":

## Disclaimer

These examples are simply for the purpose of illustration. They cannot be used as the basis for any warranty or liability claims.