RTHS Details

Reference definitions for the real-time hybrid simulation error indicators currently implemented in the MATLAB code.

Signal Pairing

The indicators use two different references. Tracking indicators compare measured displacement to the numerical sub control point. Reference indicators compare numerical sub floors or measured displacement to the full FEM reference.

Notation

Symbol Meaning
dm Measured actuator displacement response from the experiment at the interface/control point, approximately the zero-moment point around mid-column.
dc Controller command displacement saved from logsout.
dd Logged actuator command channel. It is retained in saved results but is not used for RTHS error evaluation or comparison plotting.
fm Measured force.
numerical sub Numerical sub FEM without the experimental column; measured feedback force fm is used to step this model forward.
full FEM Complete FEM model driven by the same ground excitation a_g. This is also called the reference FEM.
x1_r Full/reference FEM floor 1 response.
x1_n Numerical sub FEM floor 1 response.
x2_r Full/reference FEM floor 2 response.
x2_n Numerical sub FEM floor 2 response.
x3_r Full/reference FEM floor 3 response.
x3_n Numerical sub FEM floor 3 response.
d_r Full/reference FEM response at the interface/control point.
d_n Numerical sub interface/control-point displacement command, recomputed by stepping the numerical sub with logged fm.

Error Indicators

Indicator Code definition Unit
J1 Delay between measured dm and the numerical sub control point from finddelay(d_n, dm). ms
J2 Normalized standard-deviation error between measured dm and the numerical sub control point.

100 * std(dm - d_n) / std(d_n)

%
J3 Peak absolute error between measured dm and the numerical sub control point.

100 * max(abs(dm - d_n)) / max(abs(d_n))

%
J4 First-floor numerical sub response versus the first-floor full FEM reference.

100 * std(x1_n - x1_r) / std(x1_r)

%
J5 Second-floor numerical sub response versus the second-floor full FEM reference.

100 * std(x2_n - x2_r) / std(x2_r)

%
J6 Third-floor numerical sub response versus the third-floor full FEM reference.

100 * std(x3_n - x3_r) / std(x3_r)

%
J7 Normalized mean square error of measured dm against the full FEM control-point reference.

100 * mean((dm - u_control_ref)^2) / mean(u_control_ref^2)

%

Code Sources

compare_hs_response_to_reference.m

Shared HS utility for saved RTHS and vHS comparisons. It uses numerical sub displacement d_n for J1-J3 and for comparison plotting.

validation_metrics.m

Defines the J1-J7 metric handles and formulas.

compare_hs_test_to_reference.m

Compatibility wrapper for older calls into the shared HS response comparison utility.

vHS.m

Uses the same indicator definitions in the virtual hybrid simulation workflow.