Gyroscope

About: Gyroscope is a research topic. Over the lifetime, 17467 publications have been published within this topic receiving 159884 citations. The topic is also known as: gyroscopes.

Nuclear spin gyroscope based on an atomic comagnetometer.

Abstract: We describe a nuclear spin gyroscope based on an alkali-metal-noble-gas comagnetometer. Optically pumped alkali-metal vapor is used to polarize the noble-gas atoms and detect their gyroscopic precession. Spin precession due to magnetic fields as well as their gradients and transients can be cancelled in this arrangement. The sensitivity is enhanced by using a high-density alkali-metal vapor in a spin-exchange relaxation free regime. With a K-3He comagnetometer we demonstrate rotation sensitivity of 5 x 10(-7) rad s(-1) Hz(-1/2), equivalent to a magnetic field sensitivity of 2.5 fT/Hz(1/2). The rotation signal can be increased by a factor of 10 using 21Ne with a smaller magnetic moment. The comagnetometer is also a promising tool in searches for anomalous spin couplings beyond the standard model.

Six-axis inertial sensor using cold-atom interferometry.

Abstract: We have developed an atom interferometer providing a full inertial base. This device uses two counterpropagating cold-atom clouds that are launched in strongly curved parabolic trajectories. Three single Raman beam pairs, pulsed in time, are successively applied in three orthogonal directions leading to the measurement of the three axis of rotation and acceleration. In this purpose, we introduce a new atom gyroscope using a butterfly geometry. We discuss the present sensitivity and the possible improvements.

Active Disturbance Rejection Control for MEMS Gyroscopes

Abstract: A new control method is presented to drive the drive axis of a Micro-Electro-Mechanical Systems (MEMS) gyroscope to resonance and to regulate the output amplitude of the axis to a fixed level. It is based on a unique active disturbance rejection control (ADRC) strategy, which actively estimates and compensates for internal dynamic changes of the drive axis and external disturbances in real time. The stability analysis shows that both the estimation error and the tracking error of the drive axis output are bounded and that the upper bounds of the errors monotonously decrease with the increase of the controller bandwidth. The control system is simulated and tested using a field-programmable-gate-array-based digital implementation on a piezoelectric vibrational gyroscope. Both simulation and experimental results demonstrate that the proposed controller not only drives the drive axis to vibrate along the desired trajectory but also compensates for manufacture imperfections in a robust fashion that makes the performance of the gyroscope insensitive to parameter variations and noises. Such robustness, the fact that the control design does not require an accurate plant model, and the ease of implementation make the proposed solution practical and economic for industrial applications.

Motion sensing and processing on mobile devices

Abstract: Handheld electronic devices including motion sensing and processing. In one aspect, a handheld electronic device includes a set of motion sensors provided on a single sensor wafer, including at least one gyroscope sensing rotational rate of the device around at least three axes and at least one accelerometer sensing gravity and linear acceleration of the device along the at least three axes. Memory stores sensor data derived from the at least one gyroscope and accelerometer, where the sensor data describes movement of the device including a rotation of the device around at least one of the three axes of the device, the rotation causing interaction with the device. The memory is provided on an electronics wafer positioned vertically with respect to the sensor wafer and substantially parallel to the sensor wafer. The electronics wafer is vertically bonded to and electrically connected to the sensor wafer.

An overview of fiber-optic gyroscopes

Abstract: The principles of operation of fiber-optic gyroscopes are reviewed. Performance-limiting phenomena are discussed along with methods to reduce their effect on the rotation-rate signal. Current technology and performance of state-of-the-art systems are presented. Finally, a direction of future research and possible applications are indicated.