Design of Midcourse Trajectory for Tactical Ballistic Missile Intercept on the Basis of Zero Effort Miss

2013 ◽  
Vol 397-400 ◽  
pp. 536-545
Author(s):  
Luo Gang Li ◽  
Wu Xing Jing ◽  
Chang Sheng Gao
Keyword(s):  
Relative Motion ◽  
Design Method ◽  
Ballistic Missile ◽  
Prediction Methods ◽  
Trajectory Design ◽  
Motion State ◽  
Simulating Calculation ◽  
Analytical Expressions ◽  
Maximal Principle ◽  
Computing Method

Since the maneuverability of the tactical ballistic missile, the midcourse trajectory of interception missile needs design online. Firstly, this paper reasonably simplifies the models and explores the analytical expressions of their relative motion state to obtain a kind of rapid and high-precision computing method of zero effort miss. Secondly, it applies constant thrust for the interception missile, burns out shut-down solid engine, reflects on the index requirement of overloaded interception missile, and designs midcourse trajectory of the interception missile with Pontryagin maximal principle, in accordance with the analytical expressions of zero effort miss. Finally, with the simulating calculation, the prediction methods of zero effort miss and trajectory design method provided by this paper are applied to a situation simulation which is close to the fact as much as possible so as to verify the applicability in the interception of tactical ballistic missile.

scholarly journals CONSTRAINING THE PREFERRED-FRAME α1, α2 PARAMETERS FROM SOLAR SYSTEM PLANETARY PRECESSIONS

2014 ◽  
Vol 23 (01) ◽  
pp. 1450006 ◽  
Author(s):  
L. IORIO
Keyword(s):  
Binary System ◽  
Solar System ◽  
Relative Motion ◽  
A Priori ◽  
The Other ◽  
Preferred Frame ◽  
General Relativistic ◽  
Ppn Parameters ◽  
Invariable Plane ◽  
Analytical Expressions

Analytical expressions for the orbital precessions affecting the relative motion of the components of a local binary system induced by Lorentz-violating Preferred Frame Effects (PFE) are explicitly computed in terms of the Parametrized Post-Newtonian (PPN) parameters α1, α2. Preliminary constraints on α1, α2 are inferred from the latest determinations of the observationally admitted ranges [Formula: see text] for any anomalous Solar System planetary perihelion precessions. Other bounds existing in the literature are critically reviewed, with particular emphasis on the constraint [Formula: see text] based on an interpretation of the current close alignment of the Sun's equator with the invariable plane of the Solar System in terms of the action of a α2-induced torque throughout the entire Solar System's existence. Taken individually, the supplementary precessions [Formula: see text] of Earth and Mercury, recently determined with the INPOP10a ephemerides without modeling PFE, yield α1 = (0.8±4) × 10-6 and α2 = (4±6) × 10-6, respectively. A linear combination of the supplementary perihelion precessions of all the inner planets of the Solar System, able to remove the a priori bias of unmodeled/mismodeled standard effects such as the general relativistic Lense–Thirring precessions and the classical rates due to the Sun's oblateness J2, allows to infer α1 = (-1 ± 6) × 10-6, α2 = (-0.9 ± 3.5) × 10-5. Such figures are obtained by assuming that the ranges of values for the anomalous perihelion precessions are entirely due to the unmodeled effects of α1 and α2. Our bounds should be improved in the near-mid future with the MESSENGER and, especially, BepiColombo spacecrafts. Nonetheless, it is worthwhile noticing that our constraints are close to those predicted for BepiColombo in two independent studies. In further dedicated planetary analyses, PFE may be explicitly modeled to estimate α1, α2 simultaneously with the other PPN parameters as well.

Practical Optimization of Industrial Gravel Size in Gravel Packed Well

2011 ◽  
Vol 201-203 ◽  
pp. 383-387
Author(s):  
Jin Gen Deng ◽  
Yu Chen ◽  
Li Hua Wang ◽  
Wen Long Zhao ◽  
Ping Li
Keyword(s):  
Design Method ◽  
Control Measures ◽  
Control Effect ◽  
Gravel Layer ◽  
Gravel Size ◽  
Sand Control ◽  
Gravel Packing ◽  
Gravel Pack ◽  
The Impact ◽  
Computing Method

In the design of gravel packing sand control, the reasonable selection of gravel size is one of the keys to implementing sand control measures successfully. Aiming at the defects of commonly used methods of gravel size design and the characteristic that the gravel used in field operation is actually a mixture of gravel with multiple grain diameters, this paper builds a model of pore structure in gravel layer through researching the gravel pack structure caused by the gravel of two grain diameters mixed under actual packing conditions, calculates and analyzes the pore sizes in gravel layer. Ultimately, based on Saucier method, this paper presents a new gravel size optimization idea for gravel packing sand control with multiple grain diameters mixed, which agrees with the actual situation of industrial gravel, and gives the idea’s computing method. Considering the ideality of the model in this paper, the author has modified the computing method to make it more fit for the actual packing situation. This gravel size design method also gives consideration to the impact of formation sand uniformity on sand control effect, so it have the characteristics of good practicability, wide applicability and more accurate than other conventional methods.

scholarly journals A New Design Method for Ultrawideband Microstrip-to-Suspended Stripline Transitions

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Young-Gon Kim ◽  
Kang Wook Kim
Keyword(s):  
Conformal Mapping ◽  
Insertion Loss ◽  
Design Method ◽  
Impedance Matching ◽  
Characteristic Impedance ◽  
Ultra Wideband ◽  
Efficient Design ◽  
Em Simulation ◽  
Simulation Results ◽  
Analytical Expressions

A clear and efficient design method for ultra-wideband microstrip-to-suspended stripline transition, which is based on the analytical expressions of the whole transitional structure, is presented. The conformal mapping is applied to obtain the characteristic impedance of the transitional structure within 2.85% accuracy as compared with the EM-simulation results. The transition is designed to provide broadband impedance matching and smooth field conversion. The implemented transition performs less than 0.6 dB insertion loss per transition for frequencies up to 30 GHz.

Whole Trajectory Design Optimization of Self-Propelled Artillery Based on Adaptive Genetic Algorithm

2014 ◽  
Vol 971-973 ◽  
pp. 1391-1395
Author(s):  
Fu Qiang Niu ◽  
Cheng Xu ◽  
Xiao Xiao
Keyword(s):  
Genetic Algorithm ◽  
Trajectory Optimization ◽  
Optimization Design ◽  
Design Method ◽  
Structural Parameters ◽  
Engineering Application ◽  
The Self ◽  
Charge Weight ◽  
Adaptive Genetic Algorithm ◽  
Trajectory Design

An optimization design method of whole trajectory for a self-propelled artillery, including interior, exterior and terminal ballistic trajectory, is proposed. The structural parameters of the projectile, ballistic parameters, charge weight and explosive weight are selected as the design variables. The optimization objectives are the largest lethal area, the longest range at 45° and the highest utilization of propellant energy. Constraining the maximum bore pressure, muzzle pressure, packing density and the relative position of propellant burning end, the whole trajectory optimization model of the self-propelled is established. The model is calculated using both genetic algorithm and adaptive genetic algorithm. Optimization results show that the effect and convergence rate of the adaptive genetic algorithm are better than those of the genetic algorithm. The method in this paper play an important role in theory reference and engineering application for the whole trajectory design of the self-propelled artillery.

scholarly journals A Non-Geodesic Trajectory Design Method and Its Post-Processing for Robotic Filament Winding of Composite Tee Pipes

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 847
Author(s):  
Cheng Chang ◽  
Zhenyu Han ◽  
Xinyu Li ◽  
Shouzheng Sun ◽  
Jihao Qin ◽  
...  
Keyword(s):  
Complex Shape ◽  
Design Method ◽  
Filament Winding ◽  
Trajectory Design ◽  
Post Processing ◽  
Processing Methods ◽  
Specific Strength ◽  
Cad Cam ◽  
Winding Machine ◽  
Cam Software

With the advantages of high specific strength and well corrosion resistance, polymer-matrix composite tee pipes are widely used in aerospace and civilian fields. The robotic filament winding technology is suitable for forming complex shape parts. This paper aims to provide a novel non-geodesic trajectory design method to get a continuous trajectory for tee pipe winding. Furthermore, post-processing methods are proposed for realizing the full coverage of tee pipes by robotic filament winding. The CAD/CAM software is then designed to simulate the winding process and realize the cover of the whole tee pipe. Finally, experiments of winding a tee pipe with a desktop winding machine and a six-axis winding robot are carried out. The results show that the tee pipe is fully covered, verifying the accuracy of the design method and post-processing methods.

scholarly journals PERSPECTIVE METHODS OF DIVERGENCE OF VESSELS AND ANALYSIS OF THEIR EFFICIENCY

2020 ◽  
Vol 1 (22) ◽  
pp. 54-63
Author(s):  
Yu. M. Khussein ◽  
◽  
O. V. Yanchetskyy ◽  
Keyword(s):  
Decision Making ◽  
Collision Avoidance ◽  
Relative Motion ◽  
Relative Position ◽  
Preliminary Analysis ◽  
Decision Making Process ◽  
Rule Application ◽  
The Moment ◽  
Analytical Expressions

The article is devoted to the analysis of the most perspective and effective locally-independent methods of divergence of vessels for forming of the system of the automatic warning of collisions, providing safety of perspective autonomous vessels. Development of method of estimation of efficiency of methods of divergence of vessels, which characterizes the degree of safety of completion of process of divergence of vessels, is offered, since the moment of discovery of situation of dangerous rapprochement. The stages of process of decision-making divergence of vessels of necessity are considered at their rapprochement and choice of strategy of divergence. It is shown that a decision-making process contains the following stages: control of environment, including relative position and parameters of relative motion, exposure of situation of rapprochement of vessels, estimation of degree of danger of rapprochement and choice of strategy of divergence. Analytical expressions for formalization of the offered stages of process of decision-making divergence of vessels of necessity are resulted. It is shown that depending on the degree of danger of situation of rapprochement, it is necessary to choose strategy of divergence, coming co-ordination of maneuvers of the drawn together vessels from, foreseen ColReg. Thus character of maneuver of divergence is also determined by the value of situation indignation. As a rule, application of standard maneuver of divergence is foreseen, and in the situation of excessive rapprochement of vessels, in order to avoid the collision it is necessary to use the maneuver of urgent divergence. As the index of efficiency of the analytical collision avoidance systems vessels probability of safe completion of process of divergence, which is work of probabilities of successful finish of stages of process of decision-making on the choice of strategy of divergence, is offered. For the system of the automatic warning of collisions the methods of divergence with one dangerous target are offered by the change of course or speed of ship and with two dangerous targets by the combined maneuver of the repeated change of course of ship. After the preliminary analysis the perspective most effective methods of the mentioned types of maneuvers of divergence were offered. For the operative choice of parameters of maneuver of divergence of ship with a target the regions of impermissible values of parameters of deviation and region of acceptability parameters of deviation and output are offered. For the case of choice of maneuver of divergence of ship by the decline of speed the active or passive braking offers the method of forming of region of impermissible speeds and calculation of its scopes. In the situation of dangerous rapprochement of ship with two targets for the operative choice of parameters of maneuver of divergence of ship in work it is suggested to form the region of acceptability successive courses of deviation.

scholarly journals Hybrid Low Thrust Propulsion Trajectory Design and Optimization Using Virtual Gravity Method

2018 ◽  
Vol 36 (4) ◽  
pp. 618-626 ◽  
Author(s):  
Chong Sun ◽  
Jianping Yuan ◽  
Qun Fang ◽  
Yao Cui ◽  
Mingxiao Wang ◽  
...  
Keyword(s):  
Electric Propulsion ◽  
Design Method ◽  
Trajectory Design ◽  
Low Thrust ◽  
Design And Optimization ◽  
Solar Electric Propulsion ◽  
Spacecraft Trajectory ◽  
Rendezvous Problem ◽  
Steering Law ◽  
Thrust System

a novel spacecraft trajectory design method using hybrid low thrust system is proposed in this paper. The hybrid system is constituted with a solar sail propulsion thruster and a solar electric propulsion thruster. In proposed method, the former one provides radical thrust and circumferential thrust to from a virtual gravity, while the later one provides a tangential thrust. In this way, the spacecraft is virtually motioned by constant tangential thrust in a virtual gravity field. Using proposed method, the thrusting trajectory can be parameterized, and a large number of feasible trajectories for circle to circle rendezvous problem can be obtained. To the end the steering law to minimize the fuel cost is found using Matlab optimization tools Fmicon function, and the result is compared with traditional pure solar electric propulsion method in terms of payload mass fraction. The simulation results show that the proposed method can reduced propellant consumption significantly compared with the pure SEP system.

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