Operating method for a Coriolis gyro, and evaluation/control electronics which are suitable for this purpose
AssigneeLITEF GmbH
InventorGuenter Spahlinger
Life of this patent
Estimating the term…
Abstract
An operating method for a Coriolis gyro. Digital read signals are produced that represent a measure of the instantaneous amplitudes/frequencies of the stimulation oscillation/read oscillation of the gyro resonator. Force signals are applied to the resonator. The force signals are controlled as a function of the digital read signals so that the stimulation oscillation/read oscillation assume specific amplitudes/frequencies. The force signals are produced from quantized output signals from a pulse modulator. The modulator is fed with digital stimulation/compensation signals derived from the digital read signals.
Claims8
An operating method for a Coriolis gyro in which
- digital read signals are produced, which represent a measure of the instantaneous amplitudes/frequencies of a stimulation oscillation/read oscillation of a resonator of the Coriolis gyro, and
- force signals are applied to the resonator, with the force signals being controlled as a function of the digital read signals such that the stimulation oscillation/read oscillation assume specific amplitudes/frequencies,
- the force signals are produced from quantized output signals from a pulse modulator which is fed with digital stimulation/compensation signals which are derived from the digital read signals
- characterized in that the quantized output signals are pulse sequences at a constant frequency.
The method as claimed in one of the preceding claims, characterized in that the digital read signals are produced in such a way that
- an amount of electrical charge which flows to a moving center electrode on the basis of electrical fields which are produced by the force signals is measured by means of a charge amplifier,
- a corresponding analog output signal from the charge amplifier is converted to a digital output signal, and
- the digital read signals are determined from the output signal from the charge amplifier via signal separation, as a function of instantaneous output signal values from the pulse modulator.
Evaluation/control electronics for use in a Coriolis gyro, having:
- a unit for production of digital read signals which represent a measure of the instantaneous amplitudes/frequencies of a stimulation oscillation/read oscillation of a resonator of the Coriolis gyro,
- at least one control loop by means of which force signals are produced as a function of the digital read signals and are passed to the resonator, with the force signals being controlled such that the stimulation oscillation/read oscillation assume specific amplitudes/frequencies,
- a pulse modulator which is a part of the control loop and which is fed with digital stimulation/compensation signals which are derived from the digital read signals, in which case the force signals can be produced from quantized output signals from the pulse modulator,
- characterized in that the quantized output signals are pulse sequences at a constant frequency.
A pulse modulator for conversion of a digital complex input signal to a pulsed signal, comprising
- a subtraction stage which produces a control error signal from a difference between a digital complex input signal and a feedback signal;
- a signal conversion stage with a transfer function tending to infinity when a frequency of the control error signal tends to the value zero, which converts the control error signal to a control signal;
- a first multiplication stage, which multiplies the control signal by a complex mixing signal oscillating at a frequency ω0, and thus produces at least one of a real part and an imaginary part of a control signal up-mixed by ω0;
- a quantization stage, which quantizes the real part or the imaginary part of the control signal up-mixed by ω0 and thus produces the pulsed signal;
- a feedback unit, which uses the pulsed signal to produce the feedback signal for the subtraction stage;
- and
- the subtraction stage, the signal conversion stage, the first multiplication stage and the feedback unit have an in-phase signal path and a quadrature signal path.
Dependencies are inferred from the claim text.