In this study, the abnormal noise phenomenon generated intermittently in the shock absorber of the combat armored vehicle was approached from the side of the squeak joint to solve the phenomenon. In order to identify the cause of the noise, the factors causing friction in the shock absorber were checked from the viewpoint of problem product analysis, process, and design. As an improvement plan, by improving the non-lubricated section in the nitrogen chamber, the operating noise was reduced to a level lower than that of a general automobile engine along with the elimination of noise. Considering that this is a combat vehicle, it is judged that it has been improved so as not to affect the survivability and health of the crew during equipment operation. Through the improvement of this study, it is expected to prevent power loss and improve the emotional quality of our soldier.

Combat-armored vehicles were equipped with an automatic-fire-extinguishing system to ensure the safety of the crew and vehicle from fires on the vehicle. When a fire was occurred, the automatic-fire-extinguishing system automatically detects the fire through sensors and detection lines, sprays a fire extinguisher, and notifies the crew visually and audibly. Recently, there had been cases of automatic-fire-extinguishing systems malfunction on combat-armored vehicles. In this study, in order to resolve the automatic-fire-extinguisher's malfunction phenomenon, ground noise and inter-circuit noise generated from the fire detection line were identified, and the resistance connected on the circuit was revised to remove noise. As a result of resistance revision, the noises was eliminated and the electromotive force difference between input circuits was made constant, thereby improving the malfunction of the automatic-fire-extinguishing system. By applying the result, it was confirmed that the control device sensed a temperature similar to the actual temperature on actual vehicles, and it was confirmed that the automatic-fire-extinguishing system's malfunction phenomenon was not founded in the field vehicles after then.

A universal joint is a device that transmits the power of a combat vehicle engine to a cooling fan. The power of the engine is transmitted to the universal joint as it is without buffering, and play occurs at the joint between the drive shaft connected to the engine and the driven shaft connected to the cooling fan according to the usage time. Accordingly, the universal joint is periodically replaced, and the criterion for this is the degree of torsion of the universal joint. However, if the universal joint is not properly maintained during the replacement cycle, damage to the universal joint as well as damage to the surrounding power supply may occur. Accordingly, a backlash measuring device was developed to determine the limit of durability of the universal joint, and the limit of durability was derived through regression analysis of the backlash value according to the use time obtained from the accelerated life test.

Combat vehicles were developed in two types depending on the purpose of operation. The body of the vehicle is relatively large welded structure, and there is a quality problem in that welding deformation occurs in a certain area. Welding deformation is a problem that is inevitably generated during the welding process, and additional corrective work is performed. However, due to the structural characteristics of the welded structure of combat vehicl, there are many limitations in the correction method, which lowered the productivity. To improve this problem, we intend to establish improvement measures through analysis of the areas where welding deformation occurs and apply corrective measures suitable for welding structures of combat vehicles. For the design improvement plans, the finite element analysis were used and the correction method were applied to simulated structure to confirm the possibility. Finally, the improvement effect was confirmed by manufacturing the actual welded structure. Based on the results of this study, it is expected that the productivity of related similar welding structures as well as structures of wheeled armored vehicles, can be improved.

In this study, analyzed the cause of failure of the cardan shaft for water propulsion of an armored wheeled vehicle. During the development test(DT), the vehicle was deflected to the left on the water. As a result of the confirmation, increasing angular displacement and abrasion of SPIDER(Universal joint) occurred. As a result of a structure analysis and torsion fracture test, cause of failure is not insufficient design and strength deficit of each parts. and as a result of a simulation review of the assembly layout of each part, it was confirmed that excessive rotational vibration occurred. In order to solve this problem, improved the assembly layout of the water propulsion system and the worn SPIDER lubrication. Since there has been no occurrence of the same case between military operations so far, it has been confirmed that the improvement plan is appropriate.

The battle vehicle has six types of indicators attached to the instrument panel in consideration of the special battlefield environment. However, many problems of moisture occurred during the operation of combat vehicles. These moisture phenomena can adversely affect aesthetics and functionality. Moisture is generated on the instrument panel due to the inflow of external moist air, the desorption of the moist air inside the parts, and the fluctuation of the dew point temperature. In this paper, we try to derive the root cause of various moisture generation and provide an improvement measures for moisture control. Therefore, the failure mechanism of the instrument panel may be analyzed and the design may be changed depending on the failure factor. Furthermore, the effect of the design change is verified, and the humidity performance is evaluated.

The premature failure of the universal joint connecting the drive gear box and the cooling fan caused a deterioration in serviceability and operability. Universal joint is a device that transmits engine power to a cooling fan. Internal pin breakage and shaft separation can cause secondary damage such as cooling fan malfunction and radiator damage caused by component failure. The purpose of this paper is to analyze the damage phenomenon of universal joints caused by bundles in SPVs and to improve them. In order to verify the improvement, a single part test and a system conformance test were conducted, and durability test was conducted to confirm the improvement effect on the improved prototype. Through these, the effects of increasing the durability of the improved product were estimated.

This study is to investigate the improvement of quality and cost reduction of welding materials for combat vehicles through localization. The existing imported welding wires and localized welding wires were evaluated. The evaluation of the welding wires was performed for the feedability, chemical/mechanical properties, macro testing, and weldability. As a result of evaluation, the localized welding material met all the evaluation standard values. In addition, it showed excellent performance in terms of weldability and feedability. It is judged that the welding quality is improved thanks to the improvement of feeding characteristics through the localization of the welding material, and the fatigue of the worker is also expected to be relieved.

This study is to investigate the cause of the malfunction of the ground tracked combat vehicle rotating roller and set future direction of improvement. The integrity of the initially used plate and rotating roller was evaluated. As evaluation methods, mechanical property test, radiographic test and size checking test were performed. PA66, PA12, PET, and POM were selected among polymer materials and tested for water absorption rates. Through mechanical property test and radiographic test, the materials used initially were identified to be sound. In the evaluation of the selected four polymer materials, it was confirmed that the PET was excellent in the mechanical properties and the water absorption rate. PET is excellent in mechanical properties and water absorption.

In this paper, we compared and analyzed the performance of the GPS L1/L2 signal with GPS L1 using the navigation system. Generally the GPS receiver calculates the position of the satellite by using the ephemeris data recevied from GSP Satellites, and also calculates the position of its own using the pseudorange. This paper provides an overview of the device which can receive an GPS L1/L2, and compares the GPS L1 with the GPS L2 signal power using the simulator. It was confirmed that the GPS L1/L2 receiver and the GPS L1 receiver met the requirements of standards and it is similar to the navigation performance of the GPS L1 Receiver with the GPS L1/L2 receiver. It was also confirmed that the GPS L2 band can not correct ionospheric error in the navigation system of the combat vehicle.

This paper briefly reviews the path planning methods that are applicable to the autonomous mobile robots for the military. Two distinct path search algorithms, A* and D* that are most popular and flexible in public applications, among those reviewed are coded and analyzed in terms of combat environment assessment factors called METT+TC for the area of operations. The results imply that it is important to consider the characteristics of defense acquisition process and the specific requirements of defense operation so that the successful technology development of the Robot products is directly linked to the defense procurement of Robot products.