In case vehicle system has low travel distance and short duration of engine operation, this can be relatively susceptible to engine scuffing related problem. Users also experience inconvenience in system maintenance that they have to manually start engine periodically in cold night during winter. In order to solve such problems and improve system's life cycle, the automatic engine start system is developed. In order to develop the automatic engine start sytem for air defense system BIHO, two types of engine start sytem and the engine sub system are studied and four steps to start and control the automatic engine start system is suggested. The prototype of automatic engine start system was tested for the single assembly and vehicle-installed test and all requirement of the system was madeto prove its possible application.

Air Defense System requires fast movement of the turret to detect and attack the flying target of enemy. In order for the air defense system to operate accurately and properly, it is necessary to optimize the design of the motor brake system. The air defense system that is not designed properly has possibility of low performance of the gun turret and environment of operators. The previous air defense system had such flaw in its design and it caused much noise and current in the operation of the turret. In order to resolve this flaw, we changed the position and design of the components of the motor brake system to reduce load and achieved the 62.5% reduced current and 40% reduced noise of the motor brake system compared to the previous design.

An Automatic feed mechanism is one of the most important systems that make up the air defence gun. The System which consists of consecutive mechanisms from a magazine to the breech of automatic machine gun(Dual) carries ammunitions through the feeding pass with a high speed by the electric boosters to synchronize with gun firing speed. In order to feed the rounds smoothly without jamming, it is necessary to optimize the design of the driving torque needed to carry them and to get a proper distribution of power between rounds after performing mathematical calculation. In this study, in order to predict and prevent malfunctions of feeding and unloading ammunition, we have developed an optimal computational model using CATIA and multi-body dynamics software, ADAMS.