• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2010.05a
• /
• pp.357-358
• /
• 2010

• Journal of the Korean Society for Precision Engineering
• /
• v.15 no.6
• /
• pp.97-106
• /
• 1998

In this Paper, a fuel minimizing closed loop explicit inertial guidance algorithm for orbit injection of a rocket is developed. In the formulation, the fuel burning rate and magnitude of thrust are assumed constant. The motion of rocket is assumed to be subject to the average inverse-square gravity, but negligible effects from atmosphere. The optimum thrust angle to obtain a 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 vector is determined by using Pontryagin's maximum principle. To establish real time processing, many algorithms of onboard guidance software are simplified. The explicit guidance algorithm is simulated on the 2nd-stage flight of the N-1 rocket developed in Japan. The results show that the explicit guidance algorithm works well in the presence of the maximum $\pm$10% initial velocity and altitude errors, and exhibits better performance than the open-loop program guidance. The effects of the guidance cycle time are also examined.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2013.05a
• /
• pp.1407-1408
• /
• 2013

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1997.10a
• /
• pp.361-364
• /
• 1997

The re-enty guidance design involves trajectory optimization, generation of a reference drag acceleration profile with the satisfaction of trajectory constraints. This reference drag acceleration profile can be considered as the reference trajectory. This paper proposes the atmospheric re-entry system which is composed of longitudinal, later and range control. This paper shows the a performance of a re-entry guidance and control system using feedback linearization control and predictive control.

• 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 Institute of Control, Robotics and Systems
• /
• v.16 no.2
• /
• pp.177-187
• /
• 2010

A MTG (Multimode Tracking and Guidance) system is employed to compensate for the limitations of individual seekers such as RF (Radio frequency) or IIR (Imaging Infra-red) and to improve the overall tracking and guidance performance in jamming, clutter, and adverse weather environments. In the MTG system, tracking filter, data association, and data fusion methods are important elements to maximize the effectiveness of precision homing missile guidance. This paper proposes the formulation of a Kalman filter for the estimation of line-of-sight rate from seeker measurements in missiles guided by proportional navigation. Also, we suggest the HPDA (Highest Probability Data Association) and data fusion methods of the MTG system for target tracking in the adverse environments. Mont-Carlo simulation is employed to evaluate the overall tracking performance and guidance accuracy.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2012.05a
• /
• pp.1293-1294
• /
• 2012

• Proceedings of the PSK Conference
• /
• 2003.04a
• /
• pp.291.1-291.1
• /
• 2003

The purpose of this study is to provide KFDA's guidance for premarket notification submission and labeling for prescription use drugs of abuse in vitro diagnostic devices. To evaluate in vitro diagnostic devices the following performance characteristics should be described in detail within the submission: analytical sensitivity or minimum detection limit, cutoff concentration, specificity and cross reactivity, interference, precision, method comparison and stability. (omitted)

• International Journal of Precision Engineering and Manufacturing
• /
• v.2 no.3
• /
• pp.61-68
• /
• 2001

A linear motor has a lot of advantages in comparison with conventional feed mechanisms: high transitional speed, acceleration, high control performance and good positioning at high speed. Through the omission of a power transfer element, the linear motor shows no wear and no backlash, has along lifetime and is easy to assemble. Recently, the two types of linear motors, asynchronous and synchronous linear motors, are often applied to machine tools as a fast feed mechanism. In this paper, a comparison between the two types of linear motors as to power loss and thermal behavior is made. The heat sources of the linear motor-the electrical power loss in the motor and the frictional heat on the linear guidance-are measured and compared. Also, the temperature on the linear motor and machine structure is measured and presented.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2004.10a
• /
• pp.273-276
• /
• 2004

Dynamic model of the Korea standardized rubber-tired AGT light rail vehicle, and boundary conditions between vehicle and infrastructures (running track, guidance rail) were defined to analyze vehicular vibration behaviors occurred at the worst condition for straight running track. Using the commercialized software RecurDyn, resultant forces and vibration accelerations of car body and bogies were analyzed. Based on the Korea performance test criteria for urban transit, vertical and lateral vibration of car body were calculated and evaluated as wearing condition of guide wheels. And resultant forces between bogie guidance frame and guide rail in straight running track were analyzed. As the results, the Korea standardized rubber-tired AGT light rail vehicle satisfied the performance criteria and design requirement .