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Sequence Monte Carlo estimation for dynamic target involves recursive algorithm and predictive distributions of unobserved time varying signal based on noisy observations. A new Gaussian particle filtering based on coarse and fine-scale coupled chain sampling is presented in this paper, which approximates the posterior distributions by single Gaussians. By using a coarser scale, the target state chain...
A blind separation algorithm for restoring the original images from the blurred grayscale images is proposed, which utilizes the constrain ability of the nonholonomic natural gradient (NNG) in the independent component analysis(ICA) methods. However, the nonlinear activation function of this algorithm relates to the unavailable probability distribution of the sources closely, though it is robust to...
In this paper, a motion controller for computerized numerical control (CNC) machining is developed in accordance with open modular architecture controllers (OMAC) agreement and industry standards. The motion controller is a software package running on personal computer. It is developed based on modular structure adopting hierarchic organization mode. After analysis of software and hardware structure...
Abundant real-time image data are generated during aerial survey period. Through design of a digital storage system, data from a newly twice-imaging airborne camera device are timely and faultlessly stored in an IDE (Integrated Drive Electronics) hard disk. The system has data acquisition, storage and preview functions. Particularly, it receives data burst of nearly 58 MB/s and stores them within...
The electro-hydraulic exciter is characterized by the larger output force and amplitude. For the purpose of enhancing the frequency of electro-hydraulic vibration exciter, a new type of 2D digital directional control valve is presented. The configuration is designed with two motions freedom of a single spool, the rotary motion of the spool is driven by a stepper motor continually, the linear motion...
Aeroengine components performances deteriorate due to wearing, foreign object ingestion damage or other factors. The engine monitoring and fault diagnostics systems are developed to trace the components health condition and to help make the maintenance decision in order to avoid severe damages. Based on transient gas path measurements, the engine monitoring and diagnostics are carried out through...
In this paper, we present sliding mode observer (SMO) and sliding mode controller with perturbation estimation (SMCPE) for a micro-satellite attitude system. In view of the microsatellite attitude system where gyro is not available or gyro fails, the quaternion estimating angle rate of satellite is proposed by means of sliding mode observer. The SMO is suitable for microsatellite which is limit by...
A Kind of networked control system with packet dropout is modeled as asynchronous dynamical systems, and the integrity design of the networked control system with actuators failures is analyzed using hybrid systems technique based on fault-tolerant control theory. Parametric expression of controller is given based on feasible solution of linear matrix inequality. After detailed theoretical analysis,...
The energy dissipation of multi-layer metal plate damper is realized by dry friction caused by the micro-motion between adjacent layers when the damper is deformed. In the study, the damper is modeled with a single layer continuous beam with uniform thickness, in which the stress status is analyzed when the damper is deformed. The contact surface of the beam is simplified to discrete elements to analyze...
The requirements to maneuver a modern aircraft involve the development and realization of advanced control of a longitudinal and lateral aircraft motion. The manual control system for independent motion control of an aircraft on rolling and sideslip angles is given in [1]. The system depends upon a real-time measurement of air-dynamic coefficients of the aircraft, or requires the information from...
Improving the robustness and accuracy of strap-down north finder is a hot topic and difficult problem due to the complexity and randomness of environmental disturbance. The paper presents a data processing method composed of the wavelet compulsory decreasing noise and statistical subsection method according to the characters of its working environments. The practical data and processing results show...
A novel method of designing nonlinear robust sliding mode controller is presented to a class of nonlinear mismatched uncertain systems based on integral sliding mode and rate reaching law. Firstly, the existence of equivalent controller is guaranteed. The unmatched is will not be amplified by the discontinuous control. Then the controller based on integral sliding mode and rate reaching law is constructed...
For the fuzzy phenomenon during fatigue life prediction of key structural parts in aeronautics and astronautics, membership function is used to denote the fuzziness of fatigue damage caused by the stress nearby fatigue limit. The concept of fuzzy zone of stress is put forward and classified as safety fuzzy zone, economy fuzzy zone and compatibility fuzzy zone according to relative position among fatigue...
In this paper, the H2 performance of the missile terminal guidance system that incorporates various target maneuvers is first studied over a finite horizon. A novel approach named finite-time generalized H2 with initial conditions for a linear time-varying (LTV) system is adopted. Necessary and sufficient condition, which guarantees that the above mentioned performance measure is less than a prespecified...
Enhanced ground proximity warning system (EGPWS) is very important airborne system for flight safety. The structure of awareness alerting module in EGPWS, the design of terrain database and alerting algorithm are researched in this paper. The mathematical model of awareness alerting is built and algorithm based on terrain database is proposed. Additionally, Simulation system of EGPWS is designed and...
A comparative study of passive waveshaping filter, high frequency voltage-source fed VSF and current-source fed CSF switch mode rectifier SMR converter supplied from single-phase ac supply presented in this study. The active harmonic filter of CSF switch mode converter used to supply different loads. Active harmonic filter used to reduce the harmonics at the main supply by controlling the duty cycle...
Built-in test (BIT) has direct or indirect influence on reliability, maintainability, availability, lifecycle cost of the airborne electronic equipment. In this paper, we present a BIT optimization design approach based on the reliability. The impact of BIT on the system reliability is analyzed, and the BIT optimization design approach is mainly discussed. In the following, the NLIP (Non-Linear Integer...
A new method for orbit and attitude determination of satellite simultaneously based on three-axis-magnetometer (TAM) and gyro data is presented, which is a breakthrough in traditional pattern of treating orbit and attitude of satellite separately. Considering of the nonlinear system, a modified unscented Kalman filter is developed. The magnetic field components are used to update as measurement and...
Manufacturing execution system (MES) is defined as a system towards the level of workshop management between the schemed management system on the upper level and industrial control on the bottom level. MES is aimed at the workshops. Moreover, the workshops, acting as the manufacturing center of the enterprises, are not only the executor of production tasks, but also the feed backer of production information...
Aiming at large initial attitude errors of flight object, this paper presents perfect coupling sampling based on coupling from the past (CFTP) algorithm on MCMC (Markov chain Monte Carlo) to tackle the problem of sequential flight object attitude estimation. Based Bayesian theory, posterior distribution can be approximated by Monte Carlo likelihood function and conjunction prior distribution based...
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