In-Service Delaminations in FRP Structures under Operational Loading Conditions: Are Current Fracture Testing and Analysis on Coupons Sufficient for Capturing the Essential Effects for Reliable Predictions?

Quasi-static or cyclic loading of an artificial starter crack in unidirectionally fibre-reinforced composite test coupons yields fracture mechanics data—the toughness or strain-energy release rate (labelled G)—for characterising delamination initiation and propagation. Thus far, the reproducibility of these tests is typically between 10 and...

Spline-based wavefront reconstruction for Shack-Hartmann measurements

In the coming decade, a new generation of extremely large-scale ground-based astronomical telescopes will see first light. It is well known that increasing the size of the telescope aperture is only beneficial if the adaptive optics (AO) system, which compensates for turbulence-induced wavefront aberrations, scales accordingly. For the extreme...

GPU implementation for spline-based wavefront reconstruction

This paper presents an adaptation of the distributed-spline-based aberration reconstruction method for Shack–Hartmann (SH) slope measurements to extremely large-scale adaptive optics systems and the execution on graphics processing units (GPUs). The introduction of a hierarchical multi-level scheme for the elimination of piston offsets between...

On distributed wavefront reconstruction for large-scale adaptive optics systems

The distributed-spline-based aberration reconstruction (D-SABRE) method is proposed for distributed wavefront reconstruction with applications to large-scale adaptive optics systems. D-SABRE decomposes the wavefront sensor domain into any number of partitions and solves a local wavefront reconstruction problem on each partition using...