The micromechanical silicon resonant accelerometer has attracted considerable attention in the research and development of high-precision MEMS accelerometers because its output quasi-digital signals, high sensitivity, resolution, wide dynamic range, anti-interference capacity good stability. Because mismatching thermal expansion coefficients glass, based on Silicon Glass (SOG) technique is deeply affected by temperature during fabrication, packaging use processes. stress caused changes...

This article focuses on the bandwidth expansion of MEMS gyroscope for force-to-rebalance (FTR) rate measurement in both nondegenerate and degenerate cases. First, composition system is introduced, transfer functions operational modes are analyzed. Second, equivalent transformation simplification FTR control loop without feedthrough were performed to obtain sense modal Third, a unit negative feedback characterizing frequency characteristics formed based above function, impact factors analyzed...

<div class="section abstract"><div class="htmlview paragraph">To accurately predict the fuel consumption of vehicles, this study proposes a vehicle prediction model based on VMD-CNN-BiGRU algorithm by considering six road spatial features such as grades, one-way attributes and intersection attributes. First, VMD is employed to reduce nonlinearity nonsmoothness raw data determining optimal number decomposition modes. Then, CNN-BiGRU used each modal component after decomposition,...

ABSTRACT Foreign object damage (FOD) has been a critical issue for fan and compressor blades in aero‐engines due to the cause of high cycle fatigue (HCF) failure. To address it, anti‐fatigue design is imperative. In this paper, laser shock peening (LSP) was employed improve resistance airfoil specimens with FOD. Systematic experimental investigations were carried out determine notch geometry, residual stress, cumulative plastic are dominant factors improving HCF resistance. Compared...

This paper reports an in-run automatic mode-matching method of whole-angle (WA) micro-hemispherical resonator gyroscope ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu $ </tex-math></inline-formula> HRG) based on standing wave self-precession. When the precesses in real-time by self-precession, all information frequency mismatch contained output force quadrature suppression loop is identified least...

Aiming at the excitation coupling error caused by assembly eccentricity in micro-hemispherical resonator gyroscope ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu $ </tex-math></inline-formula> HRG), this paper proposes a method to identify coefficients using relationship between input angular velocity and forces during mode reverses. Firstly, studies influence mechanism of on displacement detection...

This paper analyzes the effect of anisotropy single crystal silicon on frequency split vibrating ring gyroscope, operated in n = 2 wineglass mode. Firstly, elastic properties including matrices and orthotropic elasticity values (100) (111) wafers were calculated using direction cosines transformed coordinate systems. The wafer was found to be in-plane isotropic. Then, splits mode gyroscopes two simulated properties. simulation results show that gyroscope is far larger than gyroscope....

This paper presents a theoretical analysis of mechanical and electrical noise in the sense channel micro-electromechanical systems (MEMS) vibratory gyroscopes. Closed-form expressions for power spectral density (PSD) equivalent rate (NER) gyroscopes open-loop force-rebalance operations are derived by using an averaged PSD model transfer function. The obtained verified through numerical simulations, demonstrating close agreements between analytic models. Based on NER, impacts modal frequency...

This study investigated the flame height and liftoff of turbulent diffusion jet flames Propane–Hydrogen mixed gas. A series experiments have been conducted to examine their with different concentrations propane hydrogen. The experimental results show that decreases increase in hydrogen concentration. accuracy Froude number for prediction has verified. is proportional flow rate, while it was inversely concentration due increased laminar speed. theoretical model incorporating speed, heat...

In order to eliminate the frequency mismatch of MEMS (Microelectromechanical Systems) gyroscopes, this paper proposes a tuning technology based on quadrature modulation signal. A sinusoidal signal having greater gyroscope operating bandwidth is applied stiffness correction combs, and containing split information then excited at output. The effects combs resonant are analyzed. principle low input excitation analyzed, system adopting designed simulated. experiments arranged verify theoretical...

This paper presents the analytical modeling, calculation, experimental validation and feedback compensation of a capacitive MEMS accelerometer based on geometric antispring structure (GAS). According to thermal drift model, asymmetrical variations in operating environment result nonlinearity, temperature scale factor (TDSF) displacement bias (TDB), were solved with force-balanced readout, electronic active calibration system, respectively. The characterization readout circuit indicates high...

A system for the launch of hypervelocity flyer plates has been developed and characterized. Laser-driven flyers were launched from substrate backed aluminum–alumina–aluminum sandwiched films. laser-induced plasma is used to drive with typical thickness 5.5 μm diameters less than 1 mm, achieve velocities a few km/s. These have many applications, micrometeorite simulation laser ignition. The considered here up three layers: an ablation layer, form plasma; insulating layer; final, thicker layer...

In this paper, we design a truly exact perfect absorbing layer (PAL) for domain truncation of the two-dimensional Helmholtz equation in an unbounded with bounded scatterers. This technique is based on complex compression coordinate transformation polar coordinates and judicious substitution unknown field artificial layer. Compared widely used perfectly matched (PML) methods, distinctive features PAL lie that (i) it sense PAL-solution identical to original solution reduced by layer; (ii)...

Abstract A four‐channel fiber loop ring‐down pressure sensor with temperature compensation based on neural networks is described.This makes use of the principle time division multiplexing, which consists series and parallel loops. The laser pulses from four‐channels can be acquired by only one detector four values are measured synchronously in our experiment. Taking mode dispersion multimode into consideration, maximum multiplexing number discussed. In addition, has been successfully used...

In this paper, a mode order optimized vibrating ring gyroscope (VRG) with high shock resistance is designed, and the improved optimization algorithm proposed to optimize structure design. The of n=2 VRG can be first by design, which helps enhance anti-shock ability increasing translational frequency avoid excessive large at same time. method based on differential evolution (DE) developed maximize VRG. At first, response analyzed. After representing working principle specific design designed...