Guest lecture at the FHNW 2026: every measurement ends in a decision

26 October 2026 · 3 min read

Slide from the guest lecture (German): the probe head, spring parallelograms, deflection on an inclined surface and stylus qualification on the reference sphere — Slide from the lecture (German): the measuring probe head and stylus qualification on the reference sphere.

On 13 October 2026 I was a guest lecturer at the University of Applied Sciences and Arts Northwestern Switzerland FHNW in Windisch for the second time, this time for mechanical engineering students. The topic: industrial metrology. Interest was high, and we spent two to three hours deep in ISO GPS.

The students brought real specification problems from their companies. We discussed and solved them together. The route was the same every time: first clarify the function of the part, then write the specification so that it secures exactly that function.

The chain behind every measurement method

My most important point was the chain behind every device. Measuring is never an end in itself. Every method is only as good as the question it is meant to answer, and in the end one decision counts: conforming or not conforming.

Function Specification Measurement strategy Inspection Decision

Four everyday questions show where this chain is needed:

Development

“What does the deviation cause?”

Tolerances and limit samples derive from the measurable form deviation and its effect.

Production and assembly

“Is the process running? Does it fit?”

Measured values show where to readjust and stop defective lots before assembly.

Supplier and incoming goods

“Who is right?”

Both sides need a traceable basis for the decision, for example at the Quality Gate.

Safety-critical

“Is it safe?”

Aerospace and active implants: depending on the part class, every part is measured, critical characteristics (CTQ) most strictly.

Prove fully first, then inspect with a reduced scope

An example from the lecture: the position of a hole. In the functional inspection of the first article we probe the cylinder at three heights and evaluate the axis over its full length. Once this proves that the hole is perpendicular, one height is enough in series production. That saves measuring time and cost, and it is permissible because the proof was provided beforehand.

Live in the room: the HYPERSCAN

For the hands-on part, the HYPERSCAN from Hexagon Manufacturing Intelligence was in the room and was tested extensively. In the end even a crutch served as the measured object, and the students immediately used the STL data from the scan for reverse engineering.

What the HYPERSCAN does differently

→No reference markers to stick on: an optical tracker knows the position of the scanner at all times.

→Part or operator may move.

→Measurement starts immediately.

Certified per VDI/VDE 2634-3, validated by a laboratory accredited to ISO/IEC 17025 (source: Hexagon, February 2026). How we use laser scanners in the laboratory is described on the 3D scanning page.

Slides for download

PDF

Guest lecture on industrial metrology, condensed version (German)

24 pages · 4.3 MB · FHNW Windisch, 13 October 2026

Download →

The condensed version contains a selection of the slides. Not included are, among others, the chapters on CSL, achievable measurement uncertainty, CMM designs and styli, contour measurement, the video measuring system and computed tomography. I am happy to answer questions about the missing chapters by e-mail.

Thanks to the FHNW for the invitation and to the students for their committed participation. The first guest lecture in October 2025 for product development students is described in the article Guest lecture at the FHNW: metrology in the product development degree programme.