scholarly journals Optimal Guidance Law with Impact-Angle Constraint and Acceleration Limit for Exo-Atmospheric Interception

Aerospace ◽  
2021 ◽  
Vol 8 (12) ◽  
pp. 358
Author(s):  
Shilei Zhao ◽  
Wanchun Chen ◽  
Liang Yang
Keyword(s):  
Performance Index ◽  
Energy Performance ◽  
Impact Angle ◽  
Angle Error ◽  
Guidance Law ◽  
Maximal Acceleration ◽  
Optimal Guidance ◽  
Total Control ◽  
Miss Distance ◽  
Impact Angle Constraint

This paper aims to develop an optimal guidance law for exo-atmospheric interception, in which impact-angle constraint and acceleration limit are considered. Firstly, an optimal control problem with constraints on terminal miss and impact-angle is formulated, in which the control energy performance index is weighted by a power function of the time-to-go. The closed-loop guidance command, which is expressed as a linear combination of zero-effort miss distance and the zero-effort angle error, is derived using a traditional order reduction transformation. Then, an analytical solution to the maximal acceleration during the flight is obtained by analyzing the boundary points and critical points of the guidance command curve. It is found that the maximal acceleration is a function of the weighted gain in the performance index. Therefore, the maximal acceleration can be efficiently limited by using the variable weighted gain. Furthermore, the relationship between the total control energy and the weighted gain is studied. As a result, a systematic method is proposed for selecting the weighted gain so as to meet the constraint of the acceleration while the total control energy is minimal. Nonlinear simulations have been carried out to test the performance of the proposed method. The results show that this method performs well in intercepting the maneuvering target with a negligible miss distance and intercept angle error. And it can tolerate a stricter acceleration limit in comparison with the typical method.

Generalized optimal impact-angle-control guidance with terminal acceleration response constraint

2017 ◽  
Vol 231 (14) ◽  
pp. 2515-2536 ◽  
Author(s):  
Hui Wang ◽  
Jiang Wang ◽  
Defu Lin
Keyword(s):  
General Expression ◽  
Impact Angle ◽  
Acceleration Response ◽  
Proportional Navigation ◽  
Guidance Law ◽  
Optimal Guidance ◽  
Terminal Constraints ◽  
Miss Distance ◽  
Guidance Laws ◽  
Impact Angle Constraint

To study the optimal impact-angle-control guidance problem with multiple terminal constraints, a generalized optimal impact-angle-control guidance law with terminal acceleration response constraint (GOIACGL-TARC) is proposed. In the deriving, a time-to-go − nth power weighted object function is adopted to derived the GOIACGL-TARC and a general expression of GOIACGL-TARC is presented. Based on the general expression of GOIACGL-TARC, three guidance laws, GOIACGL-TARC1/TACC0/TACC1 are proposed and the inheritance relationship between GOIACGL-TACC0/TACC1/TARC1 and the conventional optimal guidance law with impact angle constraint is demonstrated. Performance analysis of the proposed guidance laws shows that in the case of GOIACGL-TACC0, the terminal acceleration is not zero at n = 0 and only as n > 0, the terminal acceleration converges to zero; in the case of GOIACGL-TACC1 and GOIACGL-TARC1, GOIACGL-TARC1 can guarantee the acceleration response to reach the exactly zero value but GOIACGL-TACC1 cannot, which can only guarantee the acceleration command to reach the exactly zero value. It is pointed out that compared with the biased proportional navigation guidance law, GOIACGL-TARC1 has an outstanding guidance performance in acceleration response, miss distance, and terminal impact angle error.

scholarly journals Two-Phase Optimal Guidance Law considering Impact Angle Constraint with Bearings-Only Measurements

2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
Tianning Wang ◽  
Shengjing Tang ◽  
Jie Guo ◽  
Haoqiang Zhang
Keyword(s):  
Sliding Mode ◽  
Information Matrix ◽  
Impact Angle ◽  
Estimation Accuracy ◽  
Two Phase ◽  
Terminal Sliding Mode ◽  
Guidance Law ◽  
Optimal Guidance ◽  
The Impact ◽  
Impact Angle Constraint

The implementation of advanced guidance laws with bearings-only measurements requires estimation of the range information. To improve estimation accuracy and satisfy the impact angle constraint, this paper proposes a two-phase optimal guidance law consisting of an observing phase and an attacking phase. In the observing phase, the determinant of Fisher information matrix is maximized to achieve the optimal observability and a suboptimal solution expressed by leading angle is derived analytically. Then, a terminal sliding-mode guidance law is designed to track the desired leading angle. In the followed attacking phase, an optimal guidance law is integrated with a switching term to satisfy both the impact angle constraint and the field-of-view constraint. Finally, comparison studies of the proposed guidance law and a traditional optimal guidance law are conducted on stationary targets and maneuvering targets cases. Simulation results demonstrate that the proposed guidance law is able to improve the range observability and achieve better terminal performances including impact angle accuracy and miss distance.

Practical generalized optimal guidance law with impact angle constraint

2018 ◽  
Vol 233 (10) ◽  
pp. 3790-3809
Author(s):  
Chang-Hun Lee ◽  
Moo-Yong Ryu
Keyword(s):  
Impact Angle ◽  
Practical Significance ◽  
Velocity Variation ◽  
Practical Solution ◽  
Guidance Law ◽  
Optimal Guidance ◽  
Comparison Results ◽  
Lag Effect ◽  
Impact Angle Constraint ◽  
Guidance Problem

In this paper, we provide a practical solution to the generalized optimal guidance problem with an impact angle constraint. The optimal guidance problem with arbitrary weighting functions is extended to explicitly consider a missile dynamic lag effect as well as a missile velocity variation. Therefore, compared to existing results, the proposed result can prevent performance degradation due to the dynamic lag effect and the velocity variation, which is an essential issue in practice. Besides, since the proposed guidance law is formulated from the generalized optimal control framework, it can directly inherit a vital feature of the framework: providing an additional degree of freedom in shaping a guidance command for achieving a specific guidance operational goal. An illustrative example is provided in order to validate this property. In this study, the proposed solution is also compared with the existing solutions. The comparison results indicate that the proposed result is a more general and practical solution. Finally, numerical simulations are also conducted to demonstrate the practical significance of the proposed method.

Guidance law to control impact angle and time based on optimality of error dynamics

2018 ◽  
Vol 233 (10) ◽  
pp. 3577-3588 ◽  
Author(s):  
Bin Li ◽  
Defu Lin ◽  
Jiang Wang ◽  
Song Tian
Keyword(s):  
Impact Angle ◽  
Error Feedback ◽  
Time Error ◽  
Optimal Error ◽  
Impact Time ◽  
Guidance Law ◽  
The Difference ◽  
Error Dynamics ◽  
Miss Distance ◽  
Impact Angle Constraint

In this work, a new guidance law with a meaningful performance index is designed to satisfy terminal impact angle and impact time constraints based on optimal error dynamics, which can be used for salvo attacks or cooperative missions of multi-missile. The analytical solution of the proposed guidance law is a combination of trajectory shaping guidance law and an additional impact time error feedback term that is proportional to the difference between the desired and the true impact times. Trajectory shaping guidance law aims to achieve the desired terminal impact angle and zero miss distance, whereas the extra term aims to meet the desired impact time. The minimum and maximum feasible impact times that consider the seeker's field-of-view limit, terminal impact angle constraint, and missile's maneuvering acceleration limit are calculated to provide the feasible boundary range of the desired impact time. Numerical simulations of several engagement situations demonstrate the effectiveness of the proposed guidance law in the accuracy of terminal impact angle and impact time.

Novel guidance model and its application for optimal re-entry guidance

2018 ◽  
Vol 122 (1257) ◽  
pp. 1811-1825
Author(s):  
C.W. Jiang ◽  
G.F. Zhou ◽  
B. Yang ◽  
C.S. Gao ◽  
W.X. Jing
Keyword(s):  
Three Dimensional ◽  
Impact Angle ◽  
Guidance Law ◽  
Optimal Guidance ◽  
Entry Guidance ◽  
Independent Variable ◽  
Guidance Laws ◽  
Terminal Guidance ◽  
Impact Angle Constraint ◽  
Guidance Model

ABSTRACTAiming at three-dimensional (3D) terminal guidance problem, a novel guidance model is established in this paper, in which line-of-sight (LOS) range is treated as an independent variable, describing the relative motion between the vehicle and the target. The guidance model includes two differential equations that describe LOS’s pitch and yaw motions in which the pitch motion is separately decoupled. This model avoids the inaccuracy of simplified two-dimensional (2D) guidance model and the complexity of 3D coupled guidance model, which not only maintains the accuracy but also simplifies the guidance law design. The application of this guidance model is studied for optimal re-entry guidance law with impact angle constraint, which is presented in the form of normal overload. Compared with optimal guidance laws based on traditional guidance model, the proposed one based on novel guidance model is implemented with the LOS range instead of time-to-go, which avoids the problem of the time-to-go estimation of traditional optimal guidance laws. Finally, the correctness and validity of the guidance model and guidance law are verified by numerical simulation. The guidance model and guidance law proposed in this paper provide a new way for the design of terminal guidance.

Sign in / Sign up

Export Citation Format

Share Document