Noniterative feedback midcourse guidance for exo-atmospheric interception of ballistic targets using virtual impact point steering

2021 ◽  
pp. 107159
Author(s):  
Byeong-Un Jo ◽  
Jaemyung Ahn
Keyword(s):  
Impact Point ◽  
Midcourse Guidance

Design and Simulation of Guidance Law for a Kind of Flight Test Missile

2012 ◽  
Vol 538-541 ◽  
pp. 2887-2891
Author(s):  
Yu Qian ◽  
Xiao Jun Xiang ◽  
Jun Li Yang
Keyword(s):  
Flight Test ◽  
Target Point ◽  
Impact Point ◽  
Integral Term ◽  
Guidance Law ◽  
Velocity Information ◽  
The Difference ◽  
Miss Distance ◽  
Midcourse Guidance ◽  
The Impact

To reduce the miss distance of flight test missile, the midcourse guidance law is studied in this paper. The nonlinear projectile dynamic model is developed at first, and then designed the midcourse guidance law with the impact point prediction information. The guidance law was designed using the difference between predicting impact point and target point. To improve the guidance law’s performance, this research inducted the predicted impact point’s velocity information and integral term into guidance law command. At the end, the simulation was developed. The results of simulation show that the guidance law designed in this study is successful and it can satisfy the test missile’s flight mission requirements.

High Resolution Scanning Electron Microscopy

1991 ◽  
Vol 49 ◽  
pp. 478-479
Author(s):  
David Joy ◽  
James Pawley
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Electron Beam ◽  
Electron Microscope ◽  
High Resolution ◽  
Scanning Electron Microscope ◽  
Electron Probe ◽  
Impact Point ◽  
Interaction Volume ◽  
Scanning Electron

The scanning electron microscope (SEM) builds up an image by sampling contiguous sub-volumes near the surface of the specimen. A fine electron beam selectively excites each sub-volume and then the intensity of some resulting signal is measured. The spatial resolution of images made using such a process is limited by at least three factors. Two of these determine the size of the interaction volume: the size of the electron probe and the extent to which detectable signal is excited from locations remote from the beam impact point. A third limitation emerges from the fact that the probing beam is composed of a finite number of discrete particles and therefore that the accuracy with which any detectable signal can be measured is limited by Poisson statistics applied to this number (or to the number of events actually detected if this is smaller).

scholarly journals Influence of the Submerged Entry Nozzle’s Bottom Well on the Characteristics of Its Exit Jets

Metals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 398
Author(s):  
Jesus Gonzalez-Trejo ◽  
Cesar A. Real-Ramirez ◽  
Jose Raul Miranda-Tello ◽  
Ruslan Gabbasov ◽  
Ignacio Carvajal-Mariscal ◽  
...  
Keyword(s):  
Continuous Casting ◽  
Liquid Steel ◽  
Mold Wall ◽  
Casting Machine ◽  
Submerged Entry Nozzle ◽  
Central Plane ◽  
Impact Point ◽  
Single Vortex ◽  
Hydrodynamic Analysis ◽  
Principal Characteristics

In vertical continuous casting machines the liquid steel from the tundish is poured into the mold through the Submerged Entry Nozzle (SEN). The shape and direction of the SEN exit jets affect the liquid steel dynamics inside the mold. This work quantifies the effect of the SEN pool on the principal characteristics of the jets emerging from it, precisely, the shape, the spread angles, and the mold impact point. Experimental and numerical simulations were carried out using a SEN simplified model, a square-shaped bore nozzle with square-shaped outlet ports whose length is minimal. These experiments showed two well-defined behaviors. When a single vortex dominates the hydrodynamics inside the simplified SEN, the exit jets spread out and are misaligned about the mold’s central plane. On the contrary, when the inner flow pattern shows two vortexes, the exit jets are compact and parallel to the mold wide walls. The measured difference on the jet’s falling angles is 5°, approximately, which implies that in an actual casting machine, the impingement point at the narrow mold wall would have a variation of 0.150 m. This hydrodynamic analysis would help design new SENs for continuous casting machines that improve steel quality.

Suboptimal mid-course guidance algorithm for accelerating missiles

2016 ◽  
Vol 231 (11) ◽  
pp. 2032-2047 ◽  
Author(s):  
Min-Guk Seo ◽  
Min-Jea Tahk
Keyword(s):  
Performance Enhancement ◽  
Feedback Form ◽  
Velocity Change ◽  
Guidance Law ◽  
Burn Out ◽  
Homing Performance ◽  
Guidance Algorithm ◽  
Midcourse Guidance ◽  
Missile System ◽  
Loop Form

This paper deals with the closed-loop form of mid-course guidance law design for accelerating missile system, whose acceleration is approximately constant. A midcourse guidance algorithm of feedback form is proposed to satisfy the engagement geometry conditions at the burn-out time for terminal homing performance enhancement. The effect of velocity change due to missile acceleration is explicitly considered in the derivation of the guidance law. The terminal constraint update algorithm is proposed under the assumption that the target trajectory is predicted precisely. Simulation results are provided to show the performance and characteristics of the proposed algorithm.

An Instantaneous Impact Point Guidance for Rocket with Aerodynamics Control

2021 ◽  
Author(s):  
Ki-Wook Jung ◽  
Chang-Hun Lee ◽  
Junseong Lee ◽  
Sunghyuck Im ◽  
Keejoo Lee ◽  
...  
Keyword(s):  
Impact Point

scholarly journals Analysis of Errors in the Estimation of Impact Positions in Plate-Like Structure through the Triangulation Formula by Piezoelectric Sensors Monitoring

Sensors ◽  
2018 ◽  
Vol 18 (10) ◽  
pp. 3426 ◽  
Author(s):  
Eugenio Marino-Merlo ◽  
Andrea Bulletti ◽  
Pietro Giannelli ◽  
Marco Calzolai ◽  
Lorenzo Capineri
Keyword(s):  
Propagation Velocity ◽  
Lamb Waves ◽  
Correlation Method ◽  
Time Of Arrival ◽  
Impact Point ◽  
Laboratory Procedure ◽  
Impact Position ◽  
Set Up ◽  
Two Parameters ◽  
The Impact

The structural health monitoring (SHM) of critical structures is a complex task that involves the use of different sensors that are also aimed at the identification of the location of the impact point using ultrasonic sensors. For the evaluation of the impact position, reference is often made to the well-known triangulation method. This method requires the estimation of the differential time of arrival (DToA) and the group velocity of the Lamb waves propagating into a plate-like structure: the uncertainty of these two parameters is taken into consideration as main cause of localization error. The work proposes a simple laboratory procedure based on a set-up with a pair of sensors that are symmetrically placed with respect to the impact point, to estimate the uncertainty of the DToA and the propagation velocity estimates. According to a theoretical analysis of the error for the impact position, the experimental uncertainties of DToA and the propagation velocity are used to estimate the overall limit of the SHM system for the impact positioning. Because the error for the DToA estimate depends also on the adopted signal processing, three common methods are selected and compared: the threshold, the correlation method, and a likelihood algorithm. Finally, the analysis of the positioning error using multisensory configuration is reported as useful for the design of the SHM system.

Translunar Midcourse Guidance

Navigation ◽  
1963 ◽  
Vol 10 (2) ◽  
pp. 149-153
Author(s):  
JOHN W. HURSH
Keyword(s):  
Midcourse Guidance
Sign in / Sign up

Export Citation Format

Share Document