A Desktop Fast Hybrid Test Platform Gary Haussmann, Ph.D. George E. Brown, Jr. Network for Earthquake Engineering Simulation http://nees.colorado.edu Phone: (303) 735-0302 Fax: (303) 492-7317 [email protected] NEES at CU Boulder 01000110
Download ReportTranscript A Desktop Fast Hybrid Test Platform Gary Haussmann, Ph.D. George E. Brown, Jr. Network for Earthquake Engineering Simulation http://nees.colorado.edu Phone: (303) 735-0302 Fax: (303) 492-7317 [email protected] NEES at CU Boulder 01000110
A Desktop Fast Hybrid Test Platform Gary Haussmann, Ph.D. George E. Brown, Jr. Network for Earthquake Engineering Simulation http://nees.colorado.edu Phone: (303) 735-0302 Fax: (303) 492-7317 [email protected] NEES at CU Boulder 01000110 01001000 01010100 The George E Brown, Jr. Network for Earthquake Engineering Simulation Outline • • • • • Background Motivation and Goals Hardware Configuration Software Configuration Summary and Conclusions NEES at CU Boulder 01000110 01001000 01010100 The George E Brown, Jr. Network for Earthquake Engineering Simulation Background • Terminology: – Hybrid test: combined simulation and physical interaction – Fast Hybrid: simulation runs at/near real-time • CU-Boulder NEES site has a production FHT system for large scale tests NEES at CU Boulder 01000110 01001000 01010100 The George E Brown, Jr. Network for Earthquake Engineering Simulation Motivation • A Need for Quick FHT Sessions – Demonstrations – Educational Projects – Research Prototypes • Full-scale production system is large and expensive – Long setup/breakdown times – Complex interaction of multiple hardware boxes – Prohibitive for quick experiments NEES at CU Boulder 01000110 01001000 01010100 The George E Brown, Jr. Network for Earthquake Engineering Simulation FHT Desktop Goals • Rapid deployment • Inexpensive • Accessible NEES at CU Boulder 01000110 01001000 01010100 The George E Brown, Jr. Network for Earthquake Engineering Simulation Hardware Configuration 1. Physical Specimen – Accessed via LabView 2. Simulation Computer Physical Specimen Shaking Table NI DAQ – Real-time LabView OS – Simulation and network 3. Control Computer – Graphics and user interface Simulation Computer with Real-time OS Ethernet Display and Control MS-Windows Computer NEES at CU Boulder 01000110 01001000 01010100 The George E Brown, Jr. Network for Earthquake Engineering Simulation 1 Hardware Configuration • Physical Specimen is controlled directly by DAQs • Actuator accepts command displacement • Load cell produces measured force • LVDT produces measured displacement Command Displacement Actuator Force Load Cell Shaking Table LVDT Displacement NEES at CU Boulder 01000110 01001000 01010100 The George E Brown, Jr. Network for Earthquake Engineering Simulation 2 Hardware Configuration • Simulation/Physical Interface – Consistent with production system – Simulation sends displacement to actuator – Simulation receives force and displacement – Data sent to separate control computer Command Displacement Actuator Load Cell Shaking Table LVDT Force Simulation Ethernet Displacement NEES at CU Boulder 01000110 01001000 01010100 The George E Brown, Jr. Network for Earthquake Engineering Simulation 3 Hardware Configuration • Control computer – Graphical display of simulation state – Information about instruments/physical state – GUI to control graphics and simulation Command Displacement Actuator Load Cell Shaking Table LVDT Force Simulation Ethernet Control/GUI Displacement NEES at CU Boulder 01000110 01001000 01010100 The George E Brown, Jr. Network for Earthquake Engineering Simulation Software Configuration • Three Key Processes: – Simulation – Network – Control Computer with Real-time OS MS-Windows Computer Ethernet Network Process User Interface/ Display Process Simulation Process Real-time Portion Physical Specimen Shaking Table NEES at CU Boulder 01000110 01001000 01010100 The George E Brown, Jr. Network for Earthquake Engineering Simulation Software Configuration • Simulation Process – Runs on simulation computer – Runs as a Real-time Process – C/C++ code DLL embedded into LabView • FE Framework Details – Implicit dynamics (Alpha method) – Nonlinear formulation; iterative solution – Hybrid simulation embedded in the iterative process NEES at CU Boulder 01000110 01001000 01010100 The George E Brown, Jr. Network for Earthquake Engineering Simulation dC Software Configuration • Hybrid Equations – Command displacement – Measured displacement – Measured force ~ ~ Mdˆi1 M di tvi t 2 1/ 2 )ai t 2 (1 ) fi 1 ( fi ri ) C (vi t (1 )(1 )ai ) ~ M M t (1 )C d k i 1 K *1 ~ k ~ˆ Md i 1 Md i 1 t 2 (1 )ri k1 d iC1( k 1) d ik11 d ik1 d ik1 ri k11 ri M1( k 1) K * d iC1( k 1) d iM1( k 1) NEES at CU Boulder 01000110 01001000 01010100 The George E Brown, Jr. Network for Earthquake Engineering Simulation Software Configuration • Network Process – Runs on simulation computer – Runs as a non-real-time Process – Sends data to control computer – Sends Ethernet/IP/UDP datagrams at 30Hz rate • Network Module Details – C++ code to pack/unpack simulation state for networking NEES at CU Boulder 01000110 01001000 01010100 The George E Brown, Jr. Network for Earthquake Engineering Simulation Software Configuration • Display Process – Runs on control computer – Graphical display of most-recent known state – Asynchronous updates received from Network Process invoke display update • Display Platform Details – Object-oriented Graphics Rendering Engine (OGRE) – Full 3D, 60Hz display NEES at CU Boulder 01000110 01001000 01010100 The George E Brown, Jr. Network for Earthquake Engineering Simulation Summary & Conclusion • Low-cost Hybrid Test Platform Completed – Fast hybrid simulation – Multiple-DOF – Enables fast modification/prototyping • Planned use for incoming short course • Future work – Parallel computation – Continuum elements NEES at CU Boulder 01000110 01001000 01010100 The George E Brown, Jr. Network for Earthquake Engineering Simulation Demonstration NEES at CU Boulder 01000110 01001000 01010100 The George E Brown, Jr. Network for Earthquake Engineering Simulation