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List of Abbreviations

Table 1 Control system abbreviations.

Symbol	Description
Quadrature	Unwanted component of oscillation that interferes with estimation of the pattern angle, manifests as a result of structural imperfections
AGC	Amplitude Gain Control, closed‐loop control of drive amplitude
PLL	Phase Locked Loop, closed‐loop control system that generates an AC signal with a predetermined phase offset from the resonator
FTR	Force‐to‐rebalance, closed‐loop control system that actively drives the pattern angle to a setpoint
Quadrature null	Closed‐loop control system that actively suppresses the effects of structural imperfections within the gyroscope

Table 2 Mechanical parameters of the resonator.

Symbol	Description
f	Mean frequency of the two primary modes of the resonator
τ	Mean energy decay time constant of the resonator
Q‐factor	Ratio of stored energy to energy loss per vibration cycle (Q = τπf)
Δf	Frequency split between primary modes in Hz (Δf = fx − fy)
Δω	Frequency split between primary modes in rad/s (Δω = ωx − ωy)
Δτ−1	Measure of anisodamping within the gyroscope ()
θ ω	Angle defining the orientation of actual versus intended axes of elasticity
θ τ	Angle defining the orientation of actual versus intended axes of damping
(x, y, z)	Coordinate frame oriented along intended axes of symmetry x and y
n = 2 mode	A 4‐node degenerate mode pair of a wineglass or ring/disk system
n = 3 mode	A 6‐node degenerate mode pair of a wineglass or ring/disk system
Precession pattern	Vibration pattern formed by superposition of x and y vibratory modes, which is capable of changing its orientation (precesses) when subjected to Coriolis forces or an external forcing function
Pattern angle (θ)	Orientation of the precession pattern in degrees, which is a measure of angular rotation in a Rate Integrating Gyroscope