Model Of Gyroscope Research Articles

Simulink-based simulation platform design and faults impact analysis of attitude control systems

AbstractThe satellite attitude control system (SACS) is a complicated system. In order to reflect the relationship among different components in SACS and analyse the impact of component faults on system performance, a complete simulation platform of the SACS based on Simulink is built in this paper. With the embedding of the specific reaction flywheel, gyroscope and earth sensor model, and the design of the controller based on the quaternion feedback, the simulation platform can not only simulate the real SACS at the component level, but it can also realise the injection of component faults for analysing the system performance. Simulations are conducted to verify the performance of the simulation platform. Simulation results show that this simulation platform has the ability to accurately reflect the control performance of the SACS, and the output accuracy of the component model is high. The research results reveal that this simulation platform can provide model support for verifying the algorithm of fault diagnosis, prediction and tolerant control of the SACS. This simulation platform is easy to use and can be expanded and improved.

Development of an effective method to reduce mechanical coupling error in a micro quartz tuning fork gyroscope

To overcome the performance limitations of quartz microelectromechanical system (QMEMS) gyroscopes, which are extensively employed in various applications, a method was developed in this study to effectively reduce the zero-output error, which is primarily caused by the anisotropy of the quartz crystal. The proposed method increases the gold counterweights at the end of the tuning fork beam and trims them to reduce the zero-output error. First, the vibrations were determined by conducting a theoretical analysis of ideal and non-ideal gyroscopes. A finite element analysis and simulation were then performed on gyroscope models with five structures, and the influences of different crystal edge positions and counterweight trimming methods on the vibrations and outputs of the gyroscopes were simulated. Thereafter, by analyzing the simulation and experimental results, we verified that the addition of counterweights and an error-eliminating method can reduce the zero-output error of QMEMS gyroscopes, and that specific alternative methods can achieve similar results.

Hybrid Temperature Compensation Model of MEMS Gyroscope Based on Genetic Particle Swarm Optimization Variational Modal Decomposition and Improved Backpropagation

Hybrid Temperature Compensation Model of MEMS Gyroscope Based on Genetic Particle Swarm Optimization Variational Modal Decomposition and Improved Backpropagation

Complementary frequency electromagnetic gyroscope

This paper proposes a complementary frequency electromagnetic gyroscope. In this gyroscope, a voltage-controlled oscillator (VCO) is applied to generate complementary frequency signals and the angular rate detection is realized based on a phase-locked loop. The complementary frequency electromagnetic gyroscope can be fully realized by micro-electronic technology, which is beneficial to the miniaturization of the angular rate measurement system and has a wide application prospect. The complementary frequency electromagnetic gyroscope extends the application of the Sagnac effect and replaces the optical signal with the electromagnetic pulse signal. It can make full use of the advantages of microelectronic technology and microwave technology to realize the miniaturization of measuring components and even realize the system on a chip. In this paper, the mathematical model of the complementary frequency electromagnetic gyroscope is established and verified by simulation analysis. Theoretical analysis shows that the measured angular rate is proportional to the relative frequency difference of complementary VCO output. The simulation results indicate that the sensitivity of the complementary frequency gyroscope is 1 × 10−5 rad/s and is insensitive to noise. When the signal-to-noise ratio is lower than 0 dB, the gyroscope still has good angular rate measurement accuracy.

Square-Root Cubature Kalman Filter Based on H∞ Filter for Attitude Measurement of High-Spinning Aircraft

A novel H∞ filter called square-root cubature H∞ Kalman filter is proposed for attitude measurement of high-spinning aircraft. In this method, a combined measurement model of three-axis geomagnetic sensor and gyroscope is used, and the Euler angle algorithm model is used to reduce the state dimension and linearize the state equation, which can reduce the amount of calculation. Simultaneously, the method can be applied to the case of measurement noise uncertainty. By continuously modifying the error limiting parameters to update the measurement noise estimation, the filtering accuracy and robustness can be improved. The square-root forms enjoy a consistently improved numerical stability because all the resulting covariance matrices by QR decomposition are guaranteed to stay positive semidefinite. The algorithm is applied to the simulation experiment of attitude measurement with the combination of geomagnetic sensor and gyroscope and compared with the results of Unscented Kalman filter, cubature Kalman filter, square root cubature Kalman filter, and singular value decomposition cubature Kalman filter, which proves the effectiveness and superiority of the algorithm.

Establishing a Cyclone Gyro Model to Study the Trajectory of Tornadoes

This paper attempts to study the rotation and advance characteristics of tornadoes by experiments and theoretical analysis. A cyclone generator that simulates the characteristics of tornado is completed, and put to experiments under different wind fields in the wind tunnel laboratory. The rotation pattern and advance pattern are analyzed from both the Bernoulli Principle and precession principle. Finally, this paper makes a summary of the research done so far and puts forward the prospect of the next experiment.

Multi-position iterative recursive calibration algorithm of fiber optic gyroscope

The precision of the strapdown inertial navigation system (SINS) depended on the work precision of the gyroscope. However, many errors affect the precision of SINS even if the gyroscopes have perfect principles and structures. Before the application of the inertial navigation system (INS), the inertial components must be calibrated to ensure the performance of components, detect whether the precision of the inertial component satisfied the system, and compensate for the error of INS. According to the mathematical model of fiber optic gyroscope (FOG), we propose a multi-position iterative recursive calibration algorithm to compensate for the error of scale factor and installation of FOG. To guarantee the accuracy of the SINS, the error mathematical model of the FOG is established and compensated in the system. Finally, the calibration parameters of FOG are calibrated by the multi-position iterative recursive calibration (MPIRC) and the six-position method. The calibration results show that the accuracy of components calibration parameters of the MPIRC and the six-position is similar, but the accuracy of SINS using MPIRC is higher than that using six-position.

Accelerated Adaptive Backstepping Control of the Chaotic MEMS Gyroscope by Using the Type-2 Sequential FNN

In this paper, we propose an accelerated adaptive backstepping control algorithm based on the type2 sequential fuzzy neural network (T2SFNN) for the microelectromechanical system (MEMS) gyroscope with deadzone and constraints. Firstly, the mathematical model of the MEMS gyroscope is established to perform dynamical analyses and controller design. Then, the phase diagrams and Lyapunov exponents are presented to reveal its chaotic oscillation, which is harmful to system stability. In order to suppress oscillations derived from chaos and deadzone, an accelerated adaptive backstepping controller is proposed wherein an adaptive auxiliary is established to compensate the influence of nonsymmetric deadzone on stability performance, along with the T2SFNN designed to approximate unknown functions of dynamic systems. Furthermore, the speed function is introduced to accelerate convergence speed of the control system, and the problem of complex term explosion in traditional backstepping is successfully solved by a secondorder tracking differentiator. Finally, simulation results show that the proposed control scheme can guarantee asymptotic convergence of all signals in the closedloop system, as well as satisfying states constraints and fulfilling the purposes of chaos suppression and accelerated convergence.

Нечеткие фазовые траектории волновых твердотельных гироскопов

The paper considers elementary fuzzy oscillator models represented by hard and fuzzy second-order differential equations with hard and fuzzy initial conditions. Linear models describe wave processes in ring resonators of hemispherical resonator gyroscopes.We show that in the case 1 (a hard model with fuzzy initial conditions), when there is no internal friction (model 1), phase trajectories appear as a fuzzy centre shaped as an elliptical ring. When internal friction is present (model 2), phase trajectories appear as a fuzzy focus shaped as a circular logarithmic spiral. In the case 2, for a fuzzy hemispherical resonator gyroscope model with hard initial conditions, when there is no internal friction (model 1), a representative point of a fuzzy phase trajectory does not stop or increase its oscillations with time, meaning that the system is asymptotically unstable, while for the model 2 the origin singularity is a fuzzy stable focus. In the case 3, for a fuzzy hemispherical resonator gyroscope model with fuzzy initial conditions, when there is no internal friction (model 1), there is a fuzzy asymptotic instability in the model 1 of a hemispherical resonator gyroscope, while in the presence of internal friction (model 2), the phase trajectory is also a function of time and controls the asymptotic stability of the fuzzy model 2 of a hemispherical resonator gyroscope. Asymptotic stability is determined for all cases and models

American Academy of Sports Physical Therapy Platform Presentation Abstracts SPL1–SPL82

American Academy of Sports Physical Therapy Platform Presentation Abstracts SPL1–SPL82

Stability Criterion for Stationary Solutions of the Equations of a Multi-Current Model of a Synchronous Gyroscope in a Gimbal. 2

Stability Criterion for Stationary Solutions of the Equations of a Multi-Current Model of a Synchronous Gyroscope in a Gimbal. 2

A cross product calibration method for micro-electro mechanical system gyroscope in unmanned aerial vehicle attitude determination system

This paper presents a novel calibration method for micro-electro mechanical system gyroscope in attitude measurement system of small rotor unmanned aerial vehicles. This method is based on an observation vector and its cross product, which is especially valuable for the in-field calibration without the aid of external equipment. By analysing the error model of the tri-axial gyroscope, the principle of calibration is proposed. Compared with other algorithms, numerical simulations are performed to evaluate the effectiveness of integral form of the cross product calibration method. Experiment on the hex-rotor unmanned aerial vehicle platform shows that the proposed method has great advantages in low-cost integrated navigation system.

An Investigate on Degradation Models of Resonant Frequency and Mechanical Sensitivity for Butterfly Resonator Gyroscope

Analysis of degradation model of butterfly resonator gyroscope (BRG) is essential to predict its reliability. In order to establish the degradation model of the BRG, three parts of investigation are conducted. Firstly, an analytical model is developed to describe the effect of residual stress on the resonant frequency of excitation mode for BRG. Modal analysis of the BRG under different residual stresses (29 groups) is also simulated by finite element method (FEM), and the FEM results are close to the proposed analytical model within the range of residual stress (−24 MPa to 70 MPa). Secondly, the degradation models of resonant frequency at excitation mode and mechanical sensitivity of BRG are developed based the analytical model. Finally, the long-time static test of four BRGs at same environment temperature is designed and carried out. The test results show that the resonant frequency and mechanical sensitivity of the BRG decreases gradually with time increasing, which is consistent with the results of numerical simulation. Based on the degradation model of mechanical sensitivity, the mechanical sensitivity would degrade by 20.27% in 10 years. This work contributes to reliability evaluation and life prediction of BRG. [2019-0202]

Measuring upper arm elevation using an inertial measurement unit: An exploration of sensor fusion algorithms and gyroscope models

Many sensor fusion algorithms for analyzing human motion information collected with inertial measurement units have been reported in the scientific literature. Selecting which algorithm to use can be a challenge for ergonomists that may be unfamiliar with the strengths and limitations of the various options. In this paper, we describe fundamental differences among several algorithms, including differences in sensor fusion approach (e.g., complementary filter vs. Kalman Filter) and gyroscope error modeling (i.e., inclusion or exclusion of gyroscope bias). We then compare different sensor fusion algorithms considering the fundamentals discussed using laboratory-based measurements of upper arm elevation collected under three motion speeds. Results indicate peak displacement errors of <4.5° with a computationally efficient, non-proprietary complementary filter that did not account for gyroscope bias during each of the one-minute trials. Controlling for gyroscope bias reduced peak displacement errors to <3.0°. The complementary filters were comparable (<1° peak displacement difference) to the more complex Kalman filters.

AUTOMATED CONTROL SYSTEM OF THE SCAN ANTENNA SYSTEM

Based on the method of structural schemes, the control system of the scanning antenna system is synthesized, which is a special case of the tracking system, which, based on the given coordinates, controls the mismatch between the necessary and current values of the azimuth and elevation angles. An important feature of scanning systems is the constant movement of actuators when performing tasks of the intended purpose. Therefore, the nonlinearity of the elements of the navigation system can lead to a significant deterioration in the quality of the scan tasks. The article substantiates the block diagram of scanning on one channel, its mathematical description is determined. At the first stage, an analysis of the stability of a functionally minimal system was carried out. The need was identified for integrating the circuit with a sequentially connected speed controller of proportional-integral-differential action and a feedback signal taken from the tachometer on the axis of the engine. The speed loop was modeled to analyze its stability and ability to maintain its properties when the parameters deviate from the calculated values or the controller parameter settings are varied. A general scheme of the scanning system was built into which a nonlinear element was introduced. As a nonlinear element, a simplified model of a fiber-optic gyroscope with a deadband was chosen. In order to verify compliance with the requirements in transitional and established operating modes, as well as to evaluate the error of the system when exposed to real effects, a model experiment was conducted. The simulation results showed the high quality of the synthesized system. The control errors were investigated in the absence of a nonlinear element, as well as in its presence with a variation in the value of the width of the deadband. It is determined that high values of the width of the dead zone can lead to a breakdown of control, which must be taken into account when substantiating the requirements for such systems.

Research on practical calibration compensation method of MIMU

The Micro-inertial measurement unit (MIMU) is affected by the processing, installation and environment during its working process, which will produce large errors, resulting in low measurement precision, therefore, error calibration compensation is necessary. In this paper, a practical calibration compensation method of MIMU based on the error model of gyroscope and accelerometer was studied. The practical method uses a three-axis multi-functional turntable, which can provide high-precision angular rate and spatial position benchmark, to design the angular rate and six-position calibration scheme, and computes twenty-four error parameters of the MIMU, including zero bias, scale factor and installation error coefficient. The analysis of the experimental result shows that the precision of MIMU after calibration compensation can be improved by 1-2 orders of magnitude, which proves the effectiveness of the calibration compensation method.

UAV attitude measurement in the presence of wind disturbance

Concentrating on the issue that the existence of wind has an effect on the attitude estimation of unmanned aerial vehicle (UAV) and thereafter degrades the controllability of the UAV, based on the extended Kalman filter (EKF), an approach of UAV attitude estimation is proposed in the presence of wind interference. Firstly, attitude quaternion and drift bias of gyroscope are selected to construct the state vector, and the state equation is established based on the kinematics model of gyroscope. After that, observation equation can be obtained via using the measurement of accelerometer, magnetometer, and airspeed tube. In what follows, the EKF update equation is exploited to determine the UAV attitude. As compared to the traditional EKF and unscented Kalman filter, experimental results show that the proposed algorithm can depress the divergence of attitude angle obviously, upgrade the attitude measurement accuracy considerably, and lower the attitude angle error significantly.

Fractional-Order Finite-Time Super-Twisting Sliding Mode Control of Micro Gyroscope Based on Double-Loop Fuzzy Neural Network

This article proposes a fractional order nonsingular terminal super-twisting sliding mode control (FONT-STSMC) method for a micro gyroscope with unknown uncertainty based on the double-loop fuzzy neural network (DLFNN). First, the advantages of nonsingular terminal sliding control are adopted, a nonlinear function is used to design the sliding hyper plane, then the tracking error in the system could converge to zero in a specified finite time. Second, fractional order control can increase the order of differential and integral, which greatly improves the flexibility of control method. The fractional-order controller has some advantages that integer-order systems cannot achieve, thus obtaining better control effects than that without adding fractional order control. Furthermore, the chattering problem of control input can be effectively solved by using the super-twisting algorithm, which makes the control input smoother. Finally, the unknown model of the micro gyroscope is estimated by using the DLFNN. Because the DLFNN can adjust the base width, the center vector and the feedback gain of the inner and outer layers adaptively, the accurate approximation of the unknown model can be achieved, and the robustness and accuracy can be enhanced. The simulation results and the comparisons with conventional neural sliding mode control prove the presented scheme can realized better tracking property and estimate the unknown model more accurately.

Metoda prognozowania czasu pracy żyroskopu MEMS na podstawie testu przyspieszonej degradacji i modelu współczynnika przyspieszenia

The reliability analysis of MEMS gyroscope under long-term operating condition has become an urgent requirement with the enlargement of its application scope and the requirement of good durability. In this study we propose a lifetime prediction method for MEMS gyroscope based on accelerated degradation tests (ADTs) and acceleration factor model. Firstly, the degradation characteristic (bias instability) is extracted based on Allan variance. The effect of temperature stress on the degradation rate of bias instability is analyzed, and it shows that the degradation rate of bias instability would increase with the increase of the temperature. Secondly, the ADTs of MEMS gyroscope are designed and conducted, the degradation model of MEMS gyroscope is established based on the output voltage of MEMS gyroscope and Allan variance. Finally, the acceleration factor model of MEMS gyroscope under temperature stress is derived, and the lifetime of the MEMS gyroscope is predicted based on two group tests data under high stress level. The results show that the lifetime calculated by the acceleration factor model and mean lifetime under high stress levels is close to the mean lifetime calculated by the linear equation at normal temperature stress.

Vibration analysis of rotating thermally-stressed gyroscope, based on modified coupled displacement field method

Free lateral vibration analysis of gyroscope model is studied in this paper. This gyroscope is modeled as a rotating simply-supported beam which is under an initial thermal stress. Thermo-mechanical properties of the beam are mutable with temperature. For the first time beam is supposed to rotate around a fixed axis in which rotational displacement field is expressed as a liner function in terms of combination of axial and lateral displacements. Dynamic-vibration equations of the proposed model are derived based on the Hamilton’s principle. Due to the symmetry of the system, Navier approach is adopted as solution approach. For evaluation, current results are compared with the results available at the technical literature showing high level of accuracy. New results emerged from of this paper imply effects of rotation of the beam and thermal stresses simultaneously upon the dynamic response of beams: different values of lateral velocity factor strongly affect the frequencies of the system; however, axial velocity factor does not play any role. In short, rotation of the beam accompanied by thermal stresses are affecting the dynamic behavior of the beam-type gyroscope remarkably. Consideration of thermal stresses and rotation rates are the most vital factors in the design of a gyroscope.