A simultaneous rapid open and closed loop bode measurement plot is described
in
which testing of the servo controlled instrument occurs under closed loop conditions
using a binary pseudo-random sequence. The binary pseudo-random sequence is injected
into the servo while the system under test is operating closed loop in order to
generate bode plots for open loop and closed loop conditions. The present invention
provides measurement results approximately 1,000 times faster than a swept sinusoid
approach and provides superior dynamic range as compared to random white noise
test input sources.
