• Journal of the Korean Society for Precision Engineering
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• v.14 no.4
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• pp.22-29
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• 1997

This paper presents results on dynamic analysis of the missile initial motion arising from the missile detent force. Using ADAMS (Automatic Dynamic Analysis of Mechanical Syatem) software, a non- linear46-DOF (Degree of Freedom) model is developed for the launcher system including missile and lunch tube contact problem. From the dynamic analysis, it is found that initial angular velocity of the missile incre- ases when the missile detent force increases and also when rocket exhaust plume is taken into account. To achieve the missile launching stability, it needs to reduce the missile initial detent force and exhaust plume area of the lancher. Results of the dynamic analysis on the system natural frequency agree well with those obtained from experimental modal tests. The overall results suggest that the proposed method is a useful tool for prediction of initial missile stability as well as design of the missile launcher system.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.1017-1022
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• 1996

This paper presents results of dynamic analysis of the missile initial motion arising from the missile detent force. Using ADAMS (Automatic Dynamic Analysis of Mechanical System) software, a non-linear 46-DOF (Degree of Freedom) model is developed for the launcher system including missile and launch tube contact problem. From the dynamic analysis, it is found that initial angular velocity of the missile increases when the missile detent force increases (more than 18 g) and also rocket exhaust plume is taken into account. To achieve the missile launching s ability, it needs to reduce the missile initial detent force and exhaust plume area of the launcher. Results of the dynamic analysis on the system natural frequency agree well with those obtained from experimental modal tests. The overall results suggest that the proposed method is a useful tool for prediction of initial missile stability as well as d :sign of the missile launcher system.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.49 no.1
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• pp.21-30
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• 2021

Mid-course trajectory of the missiles equipped with seeker should be designed to detect target within FOV of seeker and to maximize the maneuverability at the point of transition to terminal guidance phase. Because the trajectory optimization problems are generally hard to obtain the analytic solutions due to its own nonlinearity with several constraints, the various numerical methods have been presented so far. In this paper, mid-course trajectory optimization problem for boost-glide missiles is calculated by using SOCP (Second-Order Cone Programming) which is one of convex optimization methods. At first, control variable augmentation scheme with a control constraint is suggested to reduce state variables of missile dynamics. And it is reformulated using a normalized time approach to cope with a free final time problem and boost time problem. Then, partial linearization and lossless convexification are used to convexify dynamic equation and control constraint, respectively. Finally, the results of the proposed method are compared with those of state-of-the-art nonlinear optimization method for verification.

• Journal of Advanced Navigation Technology
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• v.26 no.2
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• pp.47-53
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• 2022

With the recent development of defense technology, various aircraft armaments/equipments are being developed. Among them, cruise guided weapons(missile) for launching aircraft can be installed on aircraft aftersecuring reliability and safety through varioustests. In order to avoid collision with aircraft, missile separated from aircraft must release restraint of wing at the specified time, control wing in the specified direction. In order to confirm this, a test system that can control MIL-STD-1760 according to safety separation procedure and verify release performance is required. test system needs a function to check circuit for release of restraints and a function to check driving performance by controlling MIL-STD-1760. In addition, test system should be simulate environment separated from aircraft. This paper presented a testsystemthat can verify circuit and driving performance mounted on missile according to the safety separation procedure, and it was confirmed that it was normally separated from aircraft through flight tests.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.32 no.6
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• pp.72-80
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• 2004

In this paper, the design procedure of a guidance algorithm in the boosting phase of missiles with free-flight after thrust cut-off is introduced. The purpose of the guidance is to achieve a required velocity vector at the thrust cut-off. Trajectory optimizations for four cost functions are performed to investigate implementable trajectories in the pitch plane. It is observed from the optimization results that high angle of attack maneuver in the beginning of the flight are required to satisfy the constraints. The proposed guidance algorithm consists of the pitch program to produce open-loop pitch attitude command and the yaw attitude command generator to nullify the velocity to go. The pitch program utilizes the pitch attitude histories obtained from the trajectory optimization.

• Journal of the Korea Institute of Military Science and Technology
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• v.7 no.3 s.18
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• pp.30-37
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• 2004

For a proper operation of portable air defense IR terminal homing missile to the rapid intruding target, the boresight of an IR seeker of the missile should be accurately aligned with the gunner's aiming sight. Before a gunner fires the missile, he tries to keep the target within the circle of ASU ensuring the seeker to lock on the target correctly. In this paper, using an electrical seeker caging loop and IR detector signal characteristics, a precise aligning method between the seeker boresight and the LOS(Line of Sight) of ASU(Aiming Sight Unit) was studied. Although every seeker has slightly different SLA (Signal of Look Angle) output, we can get negligible alignment error through a fine tuning method of electrical caging signal. This alignment procedure was also adopted in K-PSAM system.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.68 no.1
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• pp.145-152
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• 2019

A composite guidance scheme is proposed for air-to-ground anti-tank missiles launched from an airborne platform. Long-range anti-tank missiles usually use a fiber optic line (FOL) for the datalink between an operator and the missile to obtain real-time target information and to command the missile. Also, impact angle control is used to maximize the warhead effectiveness, but it should be carefully implemented due to interference between the launch platform and the FOL. Thus, the proposed guidance scheme takes into account both impact angle and FOL constraints. Under system lag and acceleration limits, a selection method of guidance gains and calculation logic of the maximum achievable impact angle are proposed for a guideline of practical implementation. The performance of the proposed guidance scheme is investigated by nonlinear simulations with various engagement conditions.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.43 no.6
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• pp.497-506
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• 2015

A composite guidance law for impact angle control against nonstationary nonmaneuvering targets is proposed. The proposed law is based on the characteristics of proportional navigation and generates two kinds of guidance commands during the homing phase. The first command is to keep the desired look angle, and the second is to attack the target with impact angle constraint. The switch of guidance phases occurs when the specific light-of-sight(LOS) angle determined from the engagement information is satisfied. The calculation method of the maximum achievable impact angle is also proposed to design easily the desired impact angle within the missile capability. Numerical simulations are performed to investigate the performance and characteristics of the proposed law.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.46 no.10
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• pp.814-822
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• 2018

This paper proposes a guidance law for missiles with control time constraint. Because the proposed guidance law is based on a time-to-go polynomial, it has a generalized form. Also, acceleration of the proposed law converges to zero at the end of the control time, which reduces the sensitivity to the time-to-go estimation error and can increase the flight stability when the separation of the missile appears. A prediction method of the time-to-go is proposed for implementing the proposed law, and the possibility of application to the midcourse and terminal guidance phases is dealt with for exoatmospheric interception. The characteristics and performance of the proposed law are analyzed throughout various simulations.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.48 no.5
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• pp.52-58
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• 2011

The missile control system is comprised of various control systems such as autopilot, guidance law, and homing filter and so on. To design these guidance and control system, the optimization technique is widely applied at each developing stage. However, this kind of optimization requires lots of time and cost and moreover, this approach does not give an overall system optimization result. In this paper, to use the optimization tool for control system design, the optimal problem formulation is done and the performance index and constraints are considered. And finally the systematically optimized method is proposed.