• 대한전기학회논문지:전력기술부문A
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• 제48권7호
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• pp.881-888
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• 1999

Target pointing guidance steers a vehicle to point at a target point at a given range Rs. In this paper, vehicle's motions relative to the target point are modeled by differential equations. Then a target pointing guidance law is derived using optimal control theories. In addition, it is shown that the proposed guidance law can achieve the goal of target pointing guidance whatever initial headings are.

• 제어로봇시스템학회논문지
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• 제11권4호
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• pp.363-368
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• 2005

This paper proposes an LOS(line-of-sight) guidance system of a ship for path following. From the viewpoint of a control configuration, guidance is a special type of compensation algorithm that is placed in front of the controller to accomplish navigational objects. A guidance system generates a reference trajectory for trajectory tracking or path control and decides the desired velocity, position and heading angle. A control system executes commands based on a reliable guidance law during navigation. An LOS vector from the vessel to a point on the path between two way-points in straight-line navigation or a point among turning circle in turning navigation is selected, and then a heading angle is calculated to converge the desired path based on the LOS vector. The LOS guidance law is defined for the straight-line and the turning circle, respectively. The effectiveness of the suggested LOS guidance system is assured through computer simulation.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1228-1233
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• 2005

In this paper, we present a new guidance law for a reusable launch vehicle (RLV) that lands vertically after reentry. In our past studies, a guidance law was developed for a vertical/soft landing to a target point. The guidance law, which is analytically obtained, can regenerate a trajectory against disturbances because it is expressed in the form of state feedback. However, the guidance law does not necessarily guarantee a vertical/soft landing when a dynamical system such as an RLV includes a nonlinear phenomenon owing to the atmosphere of the earth. In this study, we introduce a design of the guidance law for a nonlinear system to achieve a vertical/soft landing on the ground using the exact linearization method and solving the two-point boundary-value problem for the derived linear system. Numerical simulation confirmed the validity of the proposed guidance law for an RLV in an atmospheric environment.

• Journal of Advanced Marine Engineering and Technology
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• 제29권1호
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• pp.124-131
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• 2005

This paper suggests LOS(Line-Of-Sight) guidance system of a surface vessel in straight-line navigation under ocean currents An LOS vector from the vessel to a point on the path between two way-points is decided and a heading angle is calculated to converge to follow the desired path based on the LOS vector This guidance system is called LOS guidance system. The suggested LOS guidance law has parameters to be properly chosen according to navigational environment. Parameters of LOS guidance system are optimized to reduce propulsive energy and/or position error between desired Position and present position of a ship using genetic algorithm which is a strong optimization algorithm with adaptational random search The effectiveness of the suggested LOS guidance system is assured through computer simulations.

• International Journal of Aeronautical and Space Sciences
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• 제10권1호
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• pp.46-58
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• 2009

This paper deals with design procedure of online guidance and control law for future missiles that requires agile maneuverability. For the purpose, the missile with high powered side thruster is proposed. The guidance and control law for such missiles is discussed from a point of view of optimal control theory in this paper. Minimum time problem is solved for the approximated system. It is derived that bang- bang control is optimal input from the necessary conditions of optimal solution. Feedback guidance without iterative calculation is useful for actual systems. In this paper. multiple design point method is applied to design feedback gains and feed forward inputs of the guidance and control law. The numerical results show that the proposed guidance and control law has a high -performance for wide-ranging boundary conditions.

• International Journal of Aeronautical and Space Sciences
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• 제11권2호
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• pp.118-125
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• 2010

This paper describes a mid-course guidance strategy based on the earliest intercept geometry (EIG) guidance. An analytical solution and performance validation will be addressed for generalized mid-course guidance problems in area air-defence in order to improve reachability and performance. The EIG is generated for a wide range of possible manoeuvres of the challenging missile based on the guidance algorithm using differential geometry concepts. The main idea is that a mid-course guidance law can defend the area as long as it assures that the depending area and objects are always within the defended area defined by EIG. The velocity of Intercept Point in EIG is analytically derived to control the Intercept Geometry and the defended area. The proposed method can be applied in deciding a missile launch window and launch point for the launch phase.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.469-473
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• 1992

The conventional closed-loop guidance commands are generated from a simplified point mass model for real time operations. In real situations, the generated guidance commands are applied to the original rigid body. This can cause attitude instability of the vehicle. In this paper, in order to solve the attitude instability problem in the guidance system sense, the influence of the guidance commands on a launch vehicle attitude is derived quantitatively. The checking method of the attitude stability conditions that uses Liapunov theorem is proposed, and the attitude stabilizing method is also proposed. The attitude stability is accomplished by subtracting the influence of the guidance commands that destabilize the vehicle attitude. The closed-loop guidance commands generated from the simplified point mass model may destabilize the vehicle attitude, which is verified through simulations. In this case, the vehicle attitude can be always stabilized with the proposed attitude stabilizing method without additive fuel consumption.

• 한국항공우주학회지
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• 제32권7호
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• pp.69-75
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• 2004

비행중인 다른 항공기를 회피하며 항공기를 목표점까지 유도하는 문제를 2차원 평면에서 고려하였다. 항공기는 속도의 크기가 일정한 질점이며, 제어입력으로 측가속도를 사용하는 것으로 가정하였다. 이동장애물에는 척력 포텐셜함수를 목적점에는 인력 포텐셜함수를 인공적으로 부여하여 항공기에 척력과 인력이 작용하도록 하였다. 유도/회피명령은 이들 포텐셜력과 상대속도를 사용하여 실시간으로 구현 가능한 유도/회피법칙을 구현하였다. Log 형태의 포텐셜함수를 사용하면 구현된 유도법칙은 잘 알려진 비례항법유도법칙이 되며, 회피법칙은 장애물까지 도달시간에 반비례하고 시선각 변화의 반대 방향으로 항공기를 회전시킨다. 제안된 유도/회피법칙은 시뮬레이션을 통하여 타당성을 검증하였다.

• 한국군사과학기술학회지
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• 제5권3호
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• pp.113-119
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• 2002

A target adaptive guidance(TAG) algorithm is proposed employing the near-zone signal that can be measured from an infrared seeker. The guidance order is composed of a conventional PNG command and an additional command to be calculable from an additional LOS rate between a hot point of target and a required intercept point. The characteristic of the near-zone signal is similar to that of LOS rate that is inversely proportional to the square of time-to-go. Hence the proposed scheme can be applied to real systems with no estimator for time-to-go. From analysis results on the miss distance with perfect missile and perfect seeker, it follows that the proposed TAG algorithm guarantees missile to be ideally guided to the required intercept point. And it is less affected by the TAG start time and a proportional navigation ratio than other TAG schemes using a LOS rate such as a step bias or a ramp bias.

• 한국문헌정보학회지
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• 제49권1호
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• pp.69-88
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• 2015

이 연구의 목적은 에니어그램의 성격유형별 성장지향점 도서를 활용한 독서지도의 효과 정도를 밝히는 데 있다. 이 연구에서는 J초등학교 6학년 학생 중 에니어그램 2번 유형을 대상으로 성장지향점 도서를 활용하여 독서지도를 실시하였다. 에니어그램 성격유형 2번의 성장지향점인 4번 유형의 선호도서인 자기성장 테마도서와 4번 유형의 심리적 기능인 자의식이 포함된 도서를 독서지도의 자료로 선정하였으며, 5주 동안 14회로 구성된 독서지도 프로그램을 개발하여 진행하였다. 효과성 검증을 위하여 정서지능과 자아존중감 검사를 측정도구로 하여 사전-사후 검증을 실행하였으며, 대상 학생들의 수업 참여 결과물을 분석하였다. 연구결과 프로그램에 참여한 학생들의 정서지능과 자아존중감이 향상되었다. 특히, 수업 자료로 이용된 성장지향점 도서에 대해 학생들이 높은 만족도를 나타내고 있어 성장지향점 도서를 활용한 독서지도의 효과가 있는 것으로 밝혀졌다.