Fatigue multiaxial in human gyroscope: lessons from a break

Published on 2026-07-02 | Translated from Spanish

An accident in a human gyroscope ride has brought to light an uncommon mechanical failure: the fracture of the intermediate ring shaft due to combined multiaxial fatigue. The incident, which resulted in no serious injuries, was investigated using a 3D pipeline that combined photogrammetry with Agisoft Metashape and finite element simulations in LS-DYNA. The analysis revealed how cyclic loads in multiple directions exceeded the steel's strength.

human gyroscope with broken intermediate ring, steel shaft fractured by multiaxial fatigue, visible cracks on metal surface, 3D model on screen showing FEM analysis in LS-DYNA, photogrammetry point clouds floating around, engineer inspecting the fracture with a digital magnifier, technical laboratory background with simulation monitors, cinematic engineering visualization, dramatic industrial lighting, scratched metal textures, suspended metal shavings particles, ultra-detailed photorealistic render

3D Reconstruction and Simulation of Structural Failure 🔧

The forensic team generated a digital model of the ride using Agisoft Metashape from 400 photographs of the post-accident gyroscope. This model was imported into LS-DYNA to simulate multiaxial fatigue under real operating conditions. The results showed that the shaft failed due to a combination of cyclic bending and torsion, with stress concentrations at the fillet radius. The simulation identified that the material had pre-existing microcracks undetected in routine visual inspections.

The Shaft That Said Enough, and Didn't Warn ⚙️

Apparently, the intermediate ring shaft decided to take a permanent vacation just as the gyroscope was spinning at full speed. Combined multiaxial fatigue, that silent enemy not found on maintenance checklists, proved that even the noblest steel can have a bad day. Sure, at least now we know that Agisoft and LS-DYNA can predict these mechanical dramas, even if they don't prevent the iron from getting tired of working non-stop.