A 3D pitch and impact-angle constrained guidance scheme

2018 ◽  
Vol 233 (5) ◽  
pp. 1571-1584
Author(s):  
S Aditya Varma ◽  
Mangal Kothari
Keyword(s):  
Velocity Vector ◽  
Impact Angle ◽  
Simple Approach ◽  
The Body ◽  
Computationally Efficient ◽  
Proportional Navigation ◽  
First Order ◽  
Proportional Navigation Law ◽  
Impact Angles ◽  
3D Problem

In this paper, a guidance scheme for achieving all the possible impact angles constraints for 3D engagements is proposed. For a simple and computationally efficient solution, our approach considers proportional navigation based impact-angle constrained guidance. However, the 3D proportional navigation law cannot be directly applied. This paper proposes a guidance strategy in which a 3D problem is divided into two consecutive 2D problems using a temporary target. The missile switches between the two planes using a temporary target. The paper begins with a simple approach and finally proposes a realistic solution. In all the scenarios considered, the guidance scheme achieves the desired impact angles. To further increase its effectiveness, the paper considers pitch constrained impact-angle law that drives the terminal angle of attack to zero. This ensures that the body axis of the missile will be aligned with its velocity vector at the time of impact. The effectiveness of the proposed guidance schemes are systematically verified through numerical simulations considering both kinematic and realistic models with first-order autopilot lag.

FOV constrained guidance law for nonstationary nonmaneuvering target interception with any impact angle

2021 ◽  
pp. 095441002110468
Author(s):  
Nikhil Kumar Singh ◽  
Sikha Hota
Keyword(s):  
Kinematic Model ◽  
Angular Spectrum ◽  
Impact Angle ◽  
Field Of View ◽  
Two Dimensional ◽  
Proportional Navigation ◽  
Guidance Law ◽  
Real World Applications ◽  
Target Interception ◽  
Impact Angles

This paper presents the nonstationary nonmaneuvering target interception with all possible desired impact angles in a two-dimensional (2D) aerial engagement scenario, where the target can move in any direction. The paper also considers the field-of-view (FOV) constraint for designing the guidance law so that the target is always visible while following the missile trajectory in the entire engagement time, which makes it feasible for real world applications. The guidance law is based on the pure proportional navigation (PPN) to achieve any impact angle of the entire angular spectrum. The proposed guidance law is then simulated for intercepting a nonstationary nonmaneuvering target using a kinematic model of a missile to demonstrate the efficacy of the presented scheme. A comparison with the related work existing in the literature has also been added to establish the superiority of the present work.

Polynomial guidance law for impact angle control with a seeker look angle limit

2019 ◽  
Vol 234 (3) ◽  
pp. 857-870
Author(s):  
Zhou Zhiming ◽  
Xiaoxian Yao
Keyword(s):  
Impact Angle ◽  
Line Of Sight ◽  
Time Varying ◽  
Proportional Navigation ◽  
Guidance Law ◽  
Maneuvering Targets ◽  
Nonlinear Simulations ◽  
Impact Angles ◽  
The Impact ◽  
Guidance Laws

In this paper, the impact angle control problem is investigated by applying the polynomial shaping method. By shaping the light-of-sight angle with relative range, a guidance law called range polynomial guidance is proposed, and the coefficients are determined by boundary conditions. The range polynomial guidance law can be applied to maneuvering targets. By profiling the seeker look angle with the light-of-sight angle, a guidance law called line-of-sight polynomial guidance is developed for impact angle control under a limitation on the seeker look angle. The line-of-sight polynomial guidance law is also effective in intercepting a non-maneuvering moving target at the desired impact angle. Guidance laws with different gain sets are discussed in this paper. The proposed guidance laws take the form of proportional navigation with a time-varying navigation gain. Nonlinear simulations are performed to validate the efficacy of the proposed guidance laws in various engagement conditions. Comparison with other studies demonstrates the practicality and flexibility of the proposed guidance laws in the design of desired impact angles and maximum look angles.

scholarly journals Intercepting Higher-Speed Targets Using Generalized Relative Biased Proportional Navigation

2019 ◽  
Vol 37 (4) ◽  
pp. 682-690
Author(s):  
Ronggang Wang ◽  
Shuo Tang
Keyword(s):  
High Speed ◽  
Impact Angle ◽  
Time Varying ◽  
Proportional Navigation ◽  
Guidance Law ◽  
Maneuvering Targets ◽  
Flight Path Angle ◽  
Proportional Navigation Law ◽  
The Impact ◽  
Terminal Guidance

To intercept a higher-speed target in the terminal guidance phase, this paper proposes a generalized relative biased proportional navigation (BPN) law. In order to enlarge the capture domain of the classical proportional navigation (PN) law and make full use of the maneuverability of a missile, the paper designs time-varying navigation coefficients; thus the modified PN guidance law integrates the advantages of the PN guidance law with those of the retro-PN guidance law. In order to intercept high-speed targets with impact angle constraints, the relative BPN law is introduced, and the impact angle is achieved by controlling the relative flight-path angle. In order to improve the performance of the guidance law for intercepting higher-speed maneuvering targets, some compensation measures are designed for guidance commands. Extensive simulations are conducted to verify the design features of the proportional navigation law.

Analysis of the First Order and Slowly Varying Motions of an Axisymmetric Floating Body in Bichromatic Waves

2013 ◽  
Vol 135 (1) ◽  
Author(s):  
João Pessoa ◽  
Nuno Fonseca ◽  
C. Guedes Soares
Keyword(s):  
Vertical Cylinder ◽  
Vertical Axis ◽  
Second Order ◽  
The Body ◽  
Floating Body ◽  
Drift Motion ◽  
First Order ◽  
Motion Responses ◽  
Simple Geometry ◽  
Good Agreement

The paper presents an experimental and numerical investigation on the motions of a floating body of simple geometry subjected to harmonic and biharmonic waves. The experiments were carried out in three different water depths representing shallow and deep water. The body is axisymmetric about the vertical axis, like a vertical cylinder with a rounded bottom, and it is kept in place with a soft mooring system. The experimental results include the first order motion responses, the steady drift motion offset in regular waves and the slowly varying motions due to second order interaction in biharmonic waves. The hydrodynamic problem is solved numerically with a second order boundary element method. The results show a good agreement of the numerical calculations with the experiments.

Geometric, Spatial Path Tracking Using Non-Redundant Manipulators via Speed-Ratio Control

2010 ◽  
Author(s):  
Satyajit Ambike ◽  
James P. Schmiedeler ◽  
Michael M. Stanisˇic´
Keyword(s):  
Path Tracking ◽  
Speed Ratio ◽  
Redundant Manipulators ◽  
Computationally Efficient ◽  
Third Order ◽  
Practical Advantage ◽  
First Order ◽  
Canonical Frame ◽  
Special Cases ◽  
Six Degree Of Freedom

Path tracking can be accomplished by separating the control of the desired trajectory geometry and the control of the path variable. Existing methods accomplish tracking of up to third-order geometric properties of planar paths and up to second-order properties of spatial paths using non-redundant manipulators, but only in special cases. This paper presents a novel methodology that enables the geometric tracking of a desired planar or spatial path to any order with any non-redundant regional manipulator. The governing first-order coordination equation for a spatial path-tracking problem is developed, the repeated differentiation of which generates the coordination equation of the desired order. In contrast to previous work, the equations are developed in a fixed global frame rather than a configuration-dependent canonical frame, providing a significant practical advantage. The equations are shown to be linear, and therefore, computationally efficient. As an example, the results are applied to a spatial 3-revolute mechanism that tracks a spatial path. Spatial, rigid-body guidance is achieved by applying the technique to three points on the end-effector of a six degree-of-freedom robot. A spatial 6-revolute robot is used as an illustration.

Proportional Navigation and Model Predictive Control of an Unmanned Autonomous Vehicle for Obstacle Avoidance

2018 ◽  
Author(s):  
Ryan P. Shaw ◽  
David M. Bevly
Keyword(s):  
Obstacle Avoidance ◽  
Autonomous Vehicle ◽  
Integrated System ◽  
Reference Trajectory ◽  
Ground Vehicles ◽  
Proportional Navigation ◽  
Predictive Controller ◽  
Proportional Navigation Law ◽  
Vehicle Dynamic Model ◽  
And Control

This paper presents a new approach for the guidance and control of a UGV (Unmanned Ground Vehicle). An obstacle avoidance algorithm was developed using an integrated system involving proportional navigation (PN) and a nonlinear model predictive controller (NMPC). An obstacle avoidance variant of the classical proportional navigation law generates command lateral accelerations to avoid obstacles, while the NMPC is used to track the reference trajectory given by the PN. The NMPC utilizes a lateral vehicle dynamic model. Obstacle avoidance has become a popular area of research for both unmanned aerial vehicles and unmanned ground vehicles. In this application an obstacle avoidance algorithm can take over the control of a vehicle until the obstacle is no longer a threat. The performance of the obstacle avoidance algorithm is evaluated through simulation. Simulation results show a promising approach to conditionally implemented obstacle avoidance.

scholarly journals Biased retro-proportional navigation law for interception of high-speed targets with angular constraint

2014 ◽  
Vol 10 (1) ◽  
pp. 60-65 ◽  
Author(s):  
Liang Yan ◽  
Ji-guang Zhao ◽  
Huai-rong Shen ◽  
Yuan Li
Keyword(s):  
High Speed ◽  
Proportional Navigation ◽  
Proportional Navigation Law

Prediction of First-Order Vessel Responses with Applications to Decision Support Systems

2015 ◽  
Author(s):  
Ulrik D. Nielsen ◽  
Toshio Iseki
Keyword(s):  
Decision Support ◽  
Decision Support Systems ◽  
Support Systems ◽  
Simple Approach ◽  
Full Scale ◽  
Uncertainty Measure ◽  
First Order ◽  
Future Developments ◽  
Vessel Response ◽  
Scale Data

The paper presents a practical and simple approach for making vessel response predictions. Features of the procedure include a) predictions which are scaled so to better agree with corresponding true, future values to be measured at the time the predictions apply at; and b) predictions that are assigned an uncertainty measure to reflect a level of confidence. The approach is tested with full-scale data and the obtained results/predictions agree well with measured values. Potentially, the procedure is therefore very useful in future developments of general decision support systems.

Light Dance

Leonardo ◽  
2020 ◽  
Vol 53 (1) ◽  
pp. 90-91
Author(s):  
Seth Riskin
Keyword(s):  
Simple Approach ◽  
The Body ◽  
Speed Of Light ◽  
Body Movements ◽  
Room Light ◽  
Shared Space ◽  
Surrounding Space ◽  
The Individual ◽  
Individual Body ◽  
Movement Expression

The author discusses the origin and meaning of his Light Dance artwork. The simple approach—placing a source of light on the body and thereby manipulating the illumination of the surrounding space through body movements—alters the viewer’s perception of space and time. Architecture appears malleable as the performer affects the size, shape and speed of light forms that reach from the body to the boundaries of the room. Light, in this perceptual environment, is not a mere transmitter of information between the invariant material surroundings and the eye of the viewer; light is a space-defining extension of the performer’s body that transposes movement expression from the individual body to the shared space. An inversion of subjective and objective “spaces” is realized in the experience of Light Dance wherein the prevailing conceptual hierarchy of light and vision is overcome.

HOW TO THINK THEOLOGICALLY ABOUT RIGHTS

2015 ◽  
Vol 30 (3) ◽  
pp. 402-413 ◽  
Author(s):  
Stanley Hauerwas
Keyword(s):  
Common Good ◽  
The Body ◽  
Primary Concern ◽  
First Order ◽  
Simone Weil ◽  
Moral Duties

AbstractIn this essay I offer a nuanced account of my critique of “rights” language. I argue that my primary concern is not to discount the usefulness of rights language in contemporary expressions of legal and moral duties. Rather my concern is with the overreliance on rights language such that it guards a society from acknowledging prior claims to a common good. Rights language has become too powerful when appeals to rights threatens to replace first-order moral descriptions in a manner that makes us less able to make the moral discriminations that we depend upon to be morally wise. Finally, I turn to Simone Weil and Rowan Williams, who both turn to the body to suggest a more constructive way for thinking about rights as attending to the body, which forces us to attend to contingency. Human contingency can help us resist abstractions that fail to properly account for and address bodily needs.

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