• 제어로봇시스템학회:학술대회논문집
• /
• 1991.10a
• /
• pp.419-424
• /
• 1991

In this paper, a fuel minimizing closed loop explicit inertial guidance algorithm for the orbit injection of a rocket is developed. In this formulation, the fuel burning rate and magnitude of thrust are assumed constant, and the motion of a rocket is assumed to be subject to the average inverse-square gravity, but with negligible atmospheric effects. The optimum thrust angle for obtaining the given velocity vector in the shortest time with minimizing fuel consumption is first determined, and then the additive thrust angle for targeting the final position vectors is determined by using Pontryagin's Maximum Principle. To establish the real time processing, many algorithms of the onboard guidance software are simplified. Simulations for the explicit guidance algorithm, for the 2nd-stage flight of the N-1 rocket, are carried out. The results show that the guidance algorithm works well in the presence of the maximum .+-.10 % initial velocity and altitude error. The effects of the guidance cycle time is also examined.

• Journal of Electrical Engineering and Technology
• /
• v.11 no.5
• /
• pp.1299-1304
• /
• 2016

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.36 no.8
• /
• pp.747-752
• /
• 2008

We propose a guidance law based on pursuit-evasion game solutions, and analyze its performance. The game solutions are obtained from the pursuit-evasion game solver developed by Tahk. The initial value of the game solution is used for guidance, and then the pursuit-evasion game is solved again at the next time step. In this respect, the proposed guidance laws are similar to the approach of model predictive control. The proposed guidance method is compared with proportional navigation guidance for a pursuit-evasion scenario, in which the evader always tries to maximize the capture time. According to the comparison, it has larger a capture set than ones of proportional navigation guidance law.

• Journal of Biosystems Engineering
• /
• v.20 no.3
• /
• pp.226-235
• /
• 1995

An unmanned speed sprayer was developed using a remote control and an inductive cable guidance systems to protect operators and environment from hazardous pesticides. The sprayer consists of a remote control system, an induction system, obstacle detectors, control actuators and an one-chip microcomputer. The sprayer can be operated by the induction guidance and/or remote control. The following summarize characteristics of the developed speed sprayer. 1) Both the remote control and the induction guidance operation were possible with the developed speed sprayer. 2) Sixteen functions of the forwarding, backing, halting, steering, 3-way valve for nozzles and fan operating etc. were utilized on the remote control system. 3) It was concluded that the DTMF method, having less transmitting error, performed better than the FSK method for an agricultural remote controller. A radio station may be necessary. 4) The digital inductive guidance system, consisting of five low-impedance detection coils and a window comparator circuit, performed better than the analog detecting system, guiding route using inductive voltage differential from tow detection coils.

• Journal of the Korean Society for Precision Engineering
• /
• v.9 no.1
• /
• pp.53-65
• /
• 1992

For improving the performance of maglev systems with a combined lift and guidance, it is suggested that the multivariable control systems and a secondary suspension should be added. The former is required to reject both track irregularities in vertical disturbances and wind gusts in lateral disturbances, and the latter to guarantee passengers against an unsatisfied criteria in ride quality. In this paper, bond graph model for the study of nonlinear dynamics of maglev systems with a combined lift and guidance is presented briefly. And, the secondary suspension is analyzed to understand the role of stiffness and damping factors in passive devices. Finally, LQG/LTR mulitivariable control systems are designed for the overall maglev systems with and without secondary suspension, and then the system performances in these two cases are evaluated.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.11 no.4
• /
• pp.29-35
• /
• 2008

In this paper, a new guidance law to reduce sensitivity to the initial heading errors is proposed. In order for shaping the input weights over the flight, we introduce the distribution functions expressed in terms of time-to-go and its inverse term. By applying the optimal control theory with the synthesized weights, the homing guidance law is derived. Also the characteristics of the proposed law are examined. Various computer simulations show the good performance of the proposed guidance.

• 제어로봇시스템학회:학술대회논문집
• /
• 1988.10a
• /
• pp.142-147
• /
• 1988

Free-path-type guidance system does not need a hardwired path in the environment so that it gives a mobile robot a flexible path. ln this study to achieve the free-path-type guidance system for a mobile robot which is steered by the differential steering of both drive forewheels, position recognition systems are constructed using odometer system as an internal position sensor. Two odometer systems, a auxiliary wheel odometer and a 2-encoder odometer system are constructed and path following algorithms using these odometer systems are designed and experimented. PID control type is adopted in the path following algorithms.

• Journal of Institute of Control, Robotics and Systems
• /
• v.18 no.2
• /
• pp.87-93
• /
• 2012

In this paper, a formation guidance method for UAVs (Unmanned Aerial Vehicles) to simulate the formation flight of birds proposed. The proposed method solves all issues of approaching for formation, formation keeping, and scarce chance to be collided with each UAV during formation process. Also, we design the feedforward controller to compensate the change of speed and heading for maneuvering of the leader UAV and the feedback controller to consider the response lag of the system. The stability and performance of the proposed controller is verified via numerical simulations of the full 6-Dof model of UAV.

• 제어로봇시스템학회:학술대회논문집
• /
• 1992.10a
• /
• pp.596-600
• /
• 1992

In CLOS guidance, feedback compensation of the Coriolis acceleration is used to reduce miss distance. This paper presents the effects of the bandwidth of target and missile on the optimal Coriolis acceleration compensation. A state space formulation of CLOS guidance is used to implement CLOS guidance in feedback form. And the LQR control method is applied to find the optimal feedback gain. From the analysis of the Riccati equations of the optimal control, the following facts are observed: When the target is agile, the optimal gain is reduced, since the compensation becomes ineffective. The missile bandwidth also affects the Coriolis accleration compensation. Narrower missile requires more compensation for the Coriolis acceleration.

• Journal of Advanced Navigation Technology
• /
• v.16 no.1
• /
• pp.8-15
• /
• 2012

This paper on the assumption that the target is stationary and the velocity of missile is fixed value. In three dimensional space. Using flight path angle to simultaneous control impact-time-and-angle base on a homing guidance law. The independent variable in the nonlinear engagement model is the flight path angle of the missile. The propose homing guidance law can see the controllability of impact-time-and-angle. And also can see the processing of the missile arrive at the target. It is applied to several salvo attack scenarios. The performance of the proposed guidance law is verified by simulations.