Preparing an aircraft structure for testing can take days or weeks before the first load is applied. Strain gauges and displacement sensors must be installed in the right locations and aligned with care. For large components, that preparation can become a significant part of the test schedule.
In a ZEISS case study involving Airbus and Applus+ IMA, optical measurement helped reduce setup time by several weeks per test campaign. The project demonstrates how ARAMIS can support aerospace structural testing with broader measurement coverage and less manual sensor installation.
The test article was a carbon fiber reinforced polymer fuselage section measuring approximately 6 by 4 meters, with aluminum reinforcement around its door cutouts. These openings required close attention because local structural instabilities can develop around them.
With conventional sensors, engineers must decide where to measure before testing. Small errors in strain gauge placement or orientation can affect results, while areas between sensors may remain unmeasured. Installing enough sensors to investigate a large structure also adds preparation time.
ARAMIS Optical Strain supports both digital image correlation (DIC) and optical point tracking. DIC uses camera images of a surface pattern to calculate displacement and strain across the visible, prepared measurement area.
For this project, the team applied measurement targets in a grid across the shell to track 3D displacement. They also prepared one edge of a door cutout with a random speckle pattern for full-field strain analysis. This approach avoided installing strain gauges and linear variable differential transformers (LVDTs) on the upper side of the shell.
According to ZEISS, the optical measurement setup was completed in just two workdays.
Full-field strain measurement can reveal concentrations within the measured region that were not anticipated in a simulation. Engineers can examine how strain develops around a feature and investigate locations beyond the original points of interest.
ZEISS CORRELATE also allows users to adjust virtual strain gauges, extensometers, and displacement measurement locations after testing. Within valid captured data, this flexibility helps teams investigate new questions without immediately repeating the physical test.
The project used TRITOP photogrammetry to establish a common spatial reference, a step that took approximately 30 minutes. A T-SCAN hawk 2 scan then recorded the shell in its installed condition, including deformation caused by mounting. The measured geometry was aligned with the CAD model.
ARAMIS measurements streamed into Applus+ IMA's data acquisition system, with time synchronization connecting the optical results to other test measurements. Combined with software analysis and reporting, this supported traceable documentation of the structural response.
For teams considering a similar approach, start by deciding which regions need full-field strain data and which need point-based displacement measurements. That distinction helps guide surface preparation and camera coverage.
Then check optical access throughout the expected motion. For stereo DIC, the measured surface must remain visible to both cameras. Grips, cables, and the component itself can obstruct the view as loading progresses. Our guide to overcoming line-of-sight challenges in optical testing explains how to plan around these constraints.
Planning an aerospace structural test? Talk with Trilion about your application to discuss your measurement area, optical access, and data requirements for ARAMIS strain and displacement measurement.
Based on the ZEISS success story, Reducing Test Times, Boosting Data: Aerospace Structural Testing with ZEISS ARAMIS. The project involved Airbus, Applus+ IMA, and ZEISS.