This paper reports the experimental system identification of the Jet Propul
sion Laboratory MEMS vibratory rate gyroscope. A primary objective is to es
timate the orientation of the stiffness matrix principal awes for important
sensor dynamic modes with respect to the electrode pick-offs in the sensor
An adaptive lattice filter is initially used to identify a high-order two-
input/two-output transfer function describing the input/output dynamics of
the sensor. A three-mode model is then developed from the identified input/
output model to determine the axes' orientation. The identified model, whic
h is extracted from only two seconds of input/output data, also yields the
frequency split between the sensor's modes that are exploited in detecting
the rotation rate. The principal axes' orientation and frequency split give
direct insight into the source of quadrature measurement error that corrup
ts detection of the sensor's angular rate.