Research note / Cycle 001
Where the displacement comes from
A simple fixture audit separates specimen extension from clamp movement before either is treated as material behavior.
Question and method
Can fixture slip be mistaken for specimen extension?
Compare a five-step synthetic gauge-extension trace against crosshead travel, with zero slip as control and an injected slip of 0.2 mm at the final step.
Observed behavior
The final gauge extension is 0.4 mm; crosshead travel is 0.6 mm. The difference is entirely injected fixture slip.
Interpretation and limits
No physical ribbon was tested. Force, tensile strength, fracture and material quality are not represented.
The result establishes a failure mode in this deliberately simplified software fixture. It does not validate the proposed program architecture.
Next investigation
Design a physical metrology protocol with an independent gauge channel, fixture-motion channel and stated uncertainty budget.