Software

To compensate for its relatively limited physical capability the CU FHT site has placed much emphasis on software capability. Currently, numerical simulation is performed by OpenSees which was modified to run completely on a real-time operating system, with direct access to the actuator controller. More recently, we "dissected" the code, and wrote a separate software-independent library to connect a finite element simulation with the hardware.

Current work is on an exciting new project called Mercury. This new software is being built from the ground up by our professional software developer and will greatly increase the complexity of the numerically-simulated portion of a hybrid test.

In general, as the software simulation runs computation results from the computations are written to the SCRAMNet network, which are then used by the MTS controller as a new position command for the actuators. Then, in turn, measurements are collected by the MTS controller and written back to the SCRAMNet, which are then picked up by the software simulation as a restoring force to be used in subsequent computations. This entire sequence occurs every 0.97 milliseconds, or 1,024 times per second. Recent benchmarking indicated that we can support approximately 135 degrees of freedom in a hard real-time simulation of a non-linear frame, however the purchase of a new computer in combination with Mercury will greatly increase that number.

Partial list of CU FHT software

• Mercury (developed in house)
• The Lightweight Tele-operation System (developed in house)
• OpenSees
• OpenFresco
• SIMCOR
• Matlab/Simulink
• LabvIEW
• SolidWorks