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Design of Monitoring and Control System for Multi-Tube Ignition Pulse Detonation Engine

A multi-processers monitoring and control system, which use the Lora as wireless communication technology, was designed to meet needs of mobility, safety, fast frequency adjustment, portability, none affect on PDE thrust test and so on. This paper elaborated on scheme of whole system, local high-speed signal acquisition, storage, data export and ignition control method...

High Fidelity Modeling Method of High Performance Electromechanical Actuator

The accuracy of high performance electromechanical actuator(EMA) system model has important influence on the simulation accuracy of aircraft guidance and control loop. Aiming at solving the deficiency in the reflection of EMA characteristics using traditional second-order model, a high-fidelity global coupling modular structure modeling method is proposed. Based on the analysis...

Attitude Stabilization and Trajectory Tracking Control Strategy for Civil UAV

To remove the funitional payload variation, the attitude oscillation and trajectory tracking error of civil UAV in complex environment, a combined inner and outer control strategy for the civil UAV is designed based on the interval system control theory and dynamic tracking error minimization principle, which can guarantee the attitude stabilization in inner loop and the heading...

Low-Energy-Orientated Resource Scheduling in Cloud Computing by Particle Swarm Optimization

In order to reduce the energy cost in cloud computing, this paper represents a novel energy-orientated resource scheduling method based on particle swarm optimization. The energy cost model in cloud computing environment is studied first. The optimization of energy cost is then considered as a multiobjective optimization problem, which generates the Pareto optimization set. To...

Small UAV Target Detection Model Based on Deep Neural Network

Unmanned aerial vehicle (UAV) has relatively small size and weak visual characteristics. The recognition accuracy of traditional object detection methods can decrease sharply when complex background and distraction objects exist. In this paper, we proposed a novel deep neural network (DNN) model for small UAV target recognition task. Based on the visual characteristics of...

Multivariate Splines-Based Asymmetric Aerodynamic Modeling of Morphing Aircraft

The aerodynamic parameters of morphing aircraft can vary significantly in the morphing process; the aerodynamic data model is complex and high-order nonlinear. This paper presents a new method of aerodynamic modeling of morphing aircraft by using multivariate splines. Firstly, the aerodynamic coefficient model of morphing aircraft based on the multivariate splines model structure...

Design of Unambiguous Combined Tracking Loop for GNSS Complex Subcarrier Signal

Complex subcarrier modulation signal, is a kind of BOC signal which is used complex exponential function as subcarrier, has been widely applied in GNSS(Global Navigation satellite system). The existence of multiple correlation peaks of the autocorrelation function of the complex subcarrier signal, will cause the acquisition error and tracking to the side peak when the signal is...

A Blended Continuation Method for Solving Steady Inviscid Flow

Steady flow field solving is wieldly used in aircraft aerodynamic design, efficiency of steady flow field solving has great influnence on efficiency of aircraft aerodynamic design. A continuation method that blended Laplacian operator and pseudo time marching method for solving steady inviscid flow problem is proposed. In steady flow problem, the field is usually initialized as...

Aerodynamic Design Based on Global Sensitivity Analysis Method

To deal with the problem of the difficult optimization search and expensive computational cost caused by large-scale design variables, the hierarchical optimization design system based on the global sensitivity analysis method is established in this paper. The M-OAT method is used to analyze the global sensitivity of the design variables, according to the sensitivity information...

Effect of High Speed Milling Process Parameters on the Milling Force and Surface Topography of AM50A Magnesium Alloy

Within the scope of high speed milling process parameters, analyzed and discussed the effects of spindle speed, feed rate, milling depth and milling width on milling forces in the process of high speed milling of AM50A magnesium alloy. At the same time, the influence of milling parameters on the surface roughness of AM50A magnesium alloy has been revealed by means of the...

Design of High-Performance Magnetorquer with Air Core for CubeSat

To solve the problem that how to design a big magnetic moment, small size, light weight, low power consumption magnetorquer with air core under the constraint of limited volume and power in CubSate, multiobjective optimization design method is used. Firstly, based on the structure of the square support with multiple layer of the enameled wire wrapped, the magnetic moment model...

Multi-Step Control of Chaos in the Application of Earth-Moon Orbit Transfer

A multi-step control of chaos method is proposed in this paper to reduce the flight time in the chaotic region of Earth-Moon low-energy orbit transfer. According to the motion regularity and the fact that the chaos orbit is highly sensitive to the initial conditions in the circular restricted three-body system, the optimal perturbation of chaos control at each step is calculated...

A Modified Backstepping Control and Dynamic Control Allocation Method for Command Tracking

This paper uses the modified Backstepping (BS) Control method and the Dynamic Control Allocation (DCA) method to solve the problem that when the fighter aircraft under different flight conditions, it will be adaptively tracking different commands. Firstly, we introduce the classical Lyapunov method and classical backstepping control method, and then propose a modified...

Study on Thermal Contact Resistance Estimation in Planar Medium

Thermal contact resistance(TCR) is one of the important parameters in heat transfer problems of engineering, and it is necessary to estimate the value of TCR effectively in many engineering fields. Considering the limitation of current estimation methods of TCR such as only focusing on one-dimensional thermal conduction, getting a single value of TCR merely, and the temperature...

A Study of Multi-Objective Aerodynamic Optimization Design for Variable Camber Airfoils and High Lift Devices

Aiming at the synthetical optimization of the aerodynamic performance between the low-speed condition of two-dimensional high lift devices during take-off and landing phase and the high-speed condition of variable camber airfoil during cruise phase, an aerodynamic optimization design method for high lift device based on Kriging based surrogate model and multi-objective genetic...

High Fidelity Modeling Method of High Performance Electromechanical Actuator

The accuracy of high performance electromechanical actuator(EMA) system model has important influence on the simulation accuracy of aircraft guidance and control loop. Aiming at solving the deficiency in the reflection of EMA characteristics using traditional second-order model, a high-fidelity global coupling modular structure modeling method is proposed. Based on the analysis...

Effect of High Speed Milling Process Parameters on the Milling Force and Surface Topography of AM50A Magnesium Alloy

Within the scope of high speed milling process parameters, analyzed and discussed the effects of spindle speed, feed rate, milling depth and milling width on milling forces in the process of high speed milling of AM50A magnesium alloy. At the same time, the influence of milling parameters on the surface roughness of AM50A magnesium alloy has been revealed by means of the...