• Journal of the Korean Magnetics Society
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• v.25 no.3
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• pp.83-86
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• 2015

Nowadays the weapon systems are employed air bursting munition (ABM) as smart programmable 40 mm shells which have been developed in order to hit the target with programmed munition that can be air burst after a set distance in the battlefield. In order to improve the accuracy of such a bursting time, by measuring the speed of the munition from the barrel, weapon systems calculate the exact time of flight to the target and then the time information must be inputted to the munition. In this study, we introduce a device capable of detecting a shot at K4 40 mm automatic grenade. The shot is composed of a rotating copper band to convert linear motion into rotary motion when it passes through the barrel, the steel section is exert the effect of fragment and aluminum section to give fuze information. The aluminum section was used to detect munition using eddy current method. To measure muzzle velocity by means of non-contact method, two eddy current probes separated 10 cm was employed. Time interval between two eddy current probe detection times was used as muzzle velocity. The eddy current probe was fabricated U-shape Mn-Zn ferrite core with enamelled copper wire, and 200 kHz alternating current was used to detect inductance change. Measured muzzle velocity using the developed sensor was compared to the Doppler radar system. The difference was smaller than 1%.

• Journal of the Korea Society for Simulation
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• v.29 no.3
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• pp.1-8
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• 2020

When enemy drones infiltrate large urban areas, various forms of great republics are deployed in large areas to respond. Due to the characteristics of a large number of government-run aircraft, the residual coal, other than the hit bullet, falls into various sizes of debris after its own explosion. The damage rate was analyzed by dividing the debris into anti-aircraft guns and guided weapons by deriving four factors: critical speed, fragmentation mass, initial speed of debris, and object collision speed, which can cause damage to human life as the debris falls to the ground. In the future, the North is expected to infiltrate the capital city of Seoul by operating unmanned aerial vehicles, which are asymmetric forces, and the damage could be minimized by setting up pre-fatal and fire-restricted zones to minimize casualties between responses.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.38 no.6
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• pp.547-556
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• 2010

For the safety of aircraft and accuracy of bombs, many companies have researched the new concept of adaptive kit to flying-bombs. For the long distance flying, it's normally used deployed high-aspect ratio wing because of limited volume. The probabilities of large elastic deformation and flutter are increased due to decreased stiffness of high-aspect ratio wing. In this paper, computational fluid dynamics and computational structure dynamics interaction methodology are applied for prediction of aerodynamic characteristics. FLUENT and ABAQUS are used to calculate fluid and structural dynamics. Code-bridge was made base on the compactly supported radial basis function to execute interpolation and mapping. There are some differences between rigid body and fluid-structure interaction analysis which are results of aerodynamics characteristics due to structural deformation. Small successive vibration was observed by interaction.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.3
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• pp.221-228
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• 2014

In this paper, the operational concept and the navigation algorithms for the gliding guided artillery munition are studied. The gliding guided artillery munition has wings for gliding; therefore spin of the munition should be eliminated. The previous navigation algorithms assumed a spinning munition with constant angular velocity; hence, they cannot be applied for the gliding munition. Moreover, lateral stability becomes worse due to decrease of angular momentum. Therefore, side force should be controlled to improve the stability, and the munition should maneuver, then the previous navigation algorithms for typical fixed-wing aircraft cannot be applied. In this paper, we apply the previous navigation algorithms for the spinning munition. Spin is eliminated and wings are deployed based on the estimation results, and the advanced navigation algorithm for the non-spinning munition is introduced.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.25 no.5
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• pp.405-411
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• 2012

Inside a rotorcraft fuel cell, pipes and components are located for fuel storage and fuel supply into the engine. Utility helicopters, operated in battle fields, fly at lower altitude compared to fixed-wing aircraft and hence are more likely to be exposed to gunfire. Since internal pressure of fluid increases when hit, the effect on LRU due to increase in pressure must taken into account when designing the aircraft for survivability. However, it is costly and time consuming to manufacture a fuel cell for gunfire test, and due to constraints from usage of live ammunition, related data gathered through numerical simulation is needed. In this study, numerical simulation on rotorcraft fuel cell exposed to gunfire was carried out using Autodyn to analyze bullet movement inside the fuel cell after hit, and internal pressure of fluid and equivalent stress on fuel cell assessed.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.9
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• pp.1093-1098
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• 2013

A single-crystal sapphire is used as a transparent bulletproof window material; however, few studies have investigated the dynamic behavior and fracture properties under high-speed impact. High-speed and high-resolution sequential images are required to study the interaction of the bullet with the brittle ceramic materials. In this study, a device is developed to capture the sequence of high-speed impact/penetration phenomena. This system consists of a speed measurement device, a microprocessor-based camera controller, and multiple CCD cameras. By using a linear array sensor, the speed-measuring device can measure a small (diameter: up to 1 2 mm) and fast (speed: up to Mach 3) bullet. Once a bullet is launched, it passes through the speed measurement device where its time and speed is recorded, and then, the camera controller computes the exact time of arrival to the target during flight. Then, it sends the trigger signal to the cameras and flashes with a specific delay to capture the impact images sequentially. It is almost impossible to capture high-speed images without the estimation of the time of arrival. We were able to capture high-speed images using the new system with precise accuracy.

• Journal of the Korea Society for Simulation
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• v.30 no.3
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• pp.11-17
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• 2021

The 30mm anti-aircraft gun has been developed with various types of weapon systems such as protective, protective complex, and wheel-type anti-aircraft artillery. The role of this anti-aircraft gun is an important anti-aircraft weapon in charge of air defense. Anti-aircraft weapons are tasked with defending the airspace from aircraft attacks. In particular, anti-aircraft weapons are organized in combination with mechanized units. And anti-aircraft weapons are prone to attack by enemies because they operate on the front lines of the battlefield. The enemy is expected to attack our troops by covering up or concealing as much as possible in order to increase their viability. Therefore, this study analyzed whether our 30mm anti-aircraft bullets could subdue the enemy in cover. This study analyzed the performance of 30mm anti-aircraft bullets using the M&S technique. For this study, live shooting and simulation method by M&S were used for the experiment. In this study, steel plate and plywood were used for the live shooting experiment. In addition, in the simulation process through M&S, this study used the PRODAS model, AUTODYN model, and Split-x model to analyze the trajectory, penetration, and fragmentation capability of 30mm anti-aircraft bullets. According to the experimental results, it has been proven that 30mm anti-aircraft bullets can destroy enemy armored vehicles. 30mm anti-aircraft bullets succeeded in quickly subduing enemies concealed in general buildings or forests. In this way, it was possible to minimize damage to allies in advance.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2005.11a
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• pp.479-483
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• 2005

BBU is the weapon system for the extension of range through the reduction of base drag in 155mm. It has been mass-produced since 2000. The purpose of this research is productivity increase through the reduction of process lead time. Development process is as follows. First, formulation tests about propellent and liner, Second, spin test and final firing test about end products.

• Journal of Advanced Navigation Technology
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• v.2 no.2
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• pp.84-99
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• 1998

As a part of closed-loop guidance law studies for anti-ballistic missile defense, a mid-course guidance law is proposed to engage the target with the predetermined attitude for increased terminal effectiveness. The proposed guidance law is based on the predicted target position calculated from a simplified solution of target motion and the estimates of an extended Kalman filter utilizing noisy nonlinear radar measurements. Extension of the proposed mid-course guidance to 3 dimensional engagements are also studied. Performance of the proposed mid-course guidance law together with a terminal guidance law in the form of conventional proportional navigation guidance is evaluated by a series of simulation studies.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.652-655
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• 2010

BBU attached to the 155mm is the weapon system for the extension of range through the reduction of base drag. This research focus on the development of inhibitor formulation changing cure agent from DDI to IPDI. Development process is as follows. First, the formulation test about basic property Second, the study on the application of process. Third, the tests for the quality and aging properties. The test results are satisfied with the all of the requirments. In results, this research is contributed to the stable manufacturing in the instability of supplying of cure agent.