SlideServe
Menu
Préférences
© SlideServe · v2026

Hybrid Testing; Benchmarks and Validation

benedict-levine avatar
21 diapositives · 359 Views · Oct 31, 2014

This document outlines key findings from the CU-NEES 2008 Workshop on Hybrid Testing, featuring topics such as validation between test and analytical models, error sources, and comparative results. It explores capabilities from pseudodynamic (PSD) testing to real-time applications, emphasizing the need for real-time testing, actuator limitations, and the development of damper models. Highlights include results showcasing how large amplitude tests align with analytical predictions and discussions on stiffness-based phenomena affecting real-time outcomes. The workshop emphasized the importance of refining damper models to enhance testing accuracy.

Hybrid Testing; Benchmarks and Validation - slide 1
01 / 21Hybrid Testing; Benchmarks and Validation
1 / 17

Télécharger la présentation

Hybrid Testing; Benchmarks and Validation
Une image / un lien ci-dessous est fourni (tel quel) pour télécharger la présentation

Politique de téléchargement : le contenu du site vous est fourni TEL QUEL pour votre information et votre usage personnel ; il ne peut être vendu, concédé sous licence ni partagé sur d’autres sites sans l’accord de son auteur.Le contenu vous est fourni TEL QUEL, pour votre information et votre usage personnel uniquement. Téléchargez la présentation en cliquant sur ce lien. Lors du téléchargement, si vous ne parvenez pas à télécharger une présentation, l’éditeur a peut-être supprimé le fichier de son serveur.Pendant le téléchargement, si vous ne parvenez pas à obtenir une présentation, le fichier a peut-être été supprimé par l’éditeur.

F I N

Plus de contenu associé

Transcription de la présentation
  1. Gary Haussmann Eric Stauffer Hybrid Testing;Benchmarks and Validation CU-NEES 2008 FHT Workshop

  2. Outline • Validation: Test vs. Analytical Models • Sources of error • Results and comparison • Capabilities, from PSD to Real-time • When do you need real-time? • The same test at multiple speeds • Limitations • Model size • Velocity, displacement limits CU-NEES 2008 FHT Workshop

  3. Validation Process • Well Understood Model • Predict Analytical Response • Compare With FHT Test Results CU-NEES 2008 FHT Workshop

  4. Validation: Error Sources • Actuator Lag • For a stiff specimen, lag leads to negative “damping” • For a damping specimen, lag leads to negative “mass” • MR Damper Model • Nonlinear Response • Use a Linearized Model • Measurement Error • Instrument Noise CU-NEES 2008 FHT Workshop

  5. Validation: MR Damper • Perform Simple Tests to Characterize Damper • Variety of velocities and displacements • Generate a Damper Model for Analytical Solution CU-NEES 2008 FHT Workshop

  6. Validation: Results CU-NEES 2008 FHT Workshop

  7. Validation: Results • Large amplitude tests match analytical • As amplitude decreases, lag increases in the test results • Primary error source: MR Damper model • Linearized model doesn't match near-zero response of the actual damper • Not noticeable with large signals • Revise Damper Model CU-NEES 2008 FHT Workshop

  8. Capabilities: PSD • Pseudodynamic testing • Time is not a factor • Local or Distributed Testing • No Limits on Model Size • Three Independent or Coordinated Actuators • 12+ Measurement Channels CU-NEES 2008 FHT Workshop

  9. Capabilities: Real-Time • Soft or Hard Real-Time • Limitations: • Local only • Max Model Size • Actuator Velocity Limits • Data Channel Limit (~80) • Pausing “ill-advised” CU-NEES 2008 FHT Workshop

  10. Real-Time Testing? • You don't always need real-time • Stiffness primary phenomenon • Low-frequency excitation • Real-time Situations • Velocity-based components • Rate-dependent forces • Can we model it instead? CU-NEES 2008 FHT Workshop

  11. When Real-Time Matters • A Simple Hybrid Test With MR Damper • Try Various Real-Time Methods and Compare CU-NEES 2008 FHT Workshop

  12. Various Modeling Schemes • Hard Real-Time • Soft Real-Time • “Fake” Soft Real-Time • OpenFresco OS Soft Real-Time • Interpolate/Extrapolate • Ramp-and-Hold • Scaled time: *10, *100 CU-NEES 2008 FHT Workshop

  13. Real-Time vs. Stretched Time • Velocity-based components • Impact is reduced • Slower time leads to less response • Stiffness-based components still valid • Virtual forces can emulate a velocity-based response if no real-time available • Compute velocity-based response in slow test • Requires reasonable damping model CU-NEES 2008 FHT Workshop

  14. Real-Time Test Results • Slower Tests Reduce Damper Effect • Hard To See The Difference CU-NEES 2008 FHT Workshop

  15. Real-Time Test Results • Slower Tests Reduce Damper Effect • Hard To See The Difference CU-NEES 2008 FHT Workshop

  16. Real-Time Results • Exaggerate The Differences • Assign Hard Real-Time = 100% • Assign No Damper = 0% • Scale The Rest Appropriately CU-NEES 2008 FHT Workshop

  17. Real-Time Results CU-NEES 2008 FHT Workshop

  18. Real-Time TestingAnalysis Limitations • Standard update rate: 0.97mS period • 60Hz Monitor: 16mS • Model Size • Degrees-of-freedom: 130 • Ever-increasing • Material Modeling • Complex materials take more time • Elastic Linear easiest CU-NEES 2008 FHT Workshop

  19. Real-Time TestingSpecimen Limitations • Actuator Limitations • Displacement: +-6 inches • Velocity: 10/20 inches/sec • Force: 110 or 220 Kips • Use actuator model to predict these results • Coupled and Multi-DOF test Configuration • Crosstalk and parasitic coupling • Exacerbated in real-time CU-NEES 2008 FHT Workshop

  20. Real-Time TestingBonus Capabilities • MATLAB xPC/Real-time Workshop • Also hooked into SCRAMnet • Additional modeling/analysis during test • PXI Instrument/DAQ Chassis • Analog and Digital I/O • Acquire quantities in real-time over SCRAMnet • Streaming analysis data • Visualize OpenSEES model during test • Debugging, Entertainment CU-NEES 2008 FHT Workshop

  21. Conclusion • Hybrid Test Validation • Compare test and analytical solution • Damper model main source of discrepancy • Real-time vs. slower time • Damping effects are reduced • Slower tests approach no-damping results • Hybrid testing limitations • Model size • Actuator limits CU-NEES 2008 FHT Workshop