Abstract: Apparatus, systems, and methods to control the frequency of a plurality of gyroscopes are disclosed. The gyroscopes are configured such that each individual gyroscope operates independently of one another and at the same pre-determined frequency. To accomplish this, the natural frequency of each gyroscope is determined, and a reference signal is added to the output signal of its respective gyroscope such that the sum of the natural frequency and the reference signal frequency equals the pre-determined frequency. Thus, each individual gyroscope, though it may include its own individual natural frequency, operates autonomously at the pre-determined frequency.

Abstract: Apparatus, systems, and methods to control a plurality of gyroscopes utilizing intermediate frequencies are disclosed. The gyroscopes are configured to operate at the same pre-determined intermediate frequency. To accomplish this, the natural frequency of each gyroscope is determined, and a reference signal is added to the output signal of its respective gyroscope such that the sum of the natural frequency and the reference signal frequency equals the pre-determined intermediate frequency. The output signal from each gyroscope is transmitted to a common inertial data processor, and the inertial data processor outputs a directional signal. The directional signal includes a representation of angles from an X-axis, a Y-axis, and a Z-axis. Since each signal output by the gyroscopes has the same frequency, the loss of data is decreased and the accuracy of the data increased.

Abstract: The invention is a method for reading out a vibratory rotation sensor comprising the steps of (1) driving the vibratory rotation sensor with a plurality of driving signals and (2) obtaining one or more readout signals resulting from the interaction of the driving signals and the vibratory rotation sensor. The functional dependence of all tracking-angle-dependent driving signals is expressible for a specified range of tracking-angle values as a single specific function of the tracking angle. A tracking-angle-dependent driving signal is the sum of two or more component signals where only one of the component signals is dependent on tracking angle. The single specific function specified for any one of a plurality of tracking-angle range of values can be the same as or different than the single specific function specified for any other tracking-angle range of values.

Abstract: A vibratory rotation sensor comprising a resonator, a resonator housing and a method for controlling and reading out signals from the sensor is packaged in groups of three, along with a single control and read-out electronics circuit which is either time division multiplexed, frequency multiplexed or a combination of both for the three sensors. This multiple sensor package is compact, lightweight, rugged and well suited for use as an inertial measurement instrument in several subterranean environments such as in mining, tunneling, and oil and gas drilling applications.

Abstract: The invention is a vibratory rotation sensor comprising a resonator and a housing to which the resonator is attached and a method for reading out the standing-wave orientation angle utilizing a tracking angle which is maintained equal to the orientation angle on average. The resonator is a rotationally-symmetric thin-walled object that can be made to vibrate in a plurality of standing-wave modes. The method includes applying driving voltages to housing electrodes and determining the orientation of a standing wave by performing operations on the resonator signal that arrives at a single resonator output port from one or more electrodes in close proximity to the housing electrodes. A driving voltage may include either a pair of excitation voltages or a forcing voltage or both. An excitation voltage has essentially no effect on the resonator dynamics but carries information pertaining to the tracking angle and the standing-wave parameters when it arrives at the resonator output port.

Abstract: The invention is a vibratory rotation sensor comprising a resonator and a resonator housing and a method for controlling and reading out the sensor utilizing multiplex electronics. The resonator is a rotationally-symmetric thin-walled object that can be made to vibrate in a plurality of standing-wave modes. One or more electrodes are attached to a surface of the resonator and connect to a single output port The housing has a plurality of attached electrodes in close proximity to the resonator electrodes. The method for controlling and reading out the vibratory rotation sensor includes applying driving voltages to the housing electrodes and determining the parameters of the standing waves by performing operations on the resonator signal that emerges from the resonator output port. A driving voltage may include either an excitation voltage or a forcing voltage or both.