KCEV(Korean Combat Engineer Vehicle) perform the mission of removing mines and various military obstacles buried in the battlefield and opening passageways. It is characterized by modifying the chassis of the K1 series tank and equipping it with an excavator, track-width mine plough, and magnetic signature duplicator. KCEV has a steering wheel, and steering force is transmitted to the transmission steering lever through the steering linkage and acceleration linkage. KCEV can be steered in up to 3 gears, and it was confirmed that there was a risk of interference with the acceleration linkage as a bending occurred in the steering linkage when steering to the right in 3 gears. In this study, we examined the bending of the acceleration linkage and proposed a method to increase the stiffness of the acceleration linkage tube to improve it. Structural analysis was conducted to confirm the effect of increasing rigidity, and the improvement was confirmed by applying it to an actual vehicle. As a result, it was confirmed that not only the bending displacement of the steering linkage was reduced, but also the stress in the bent area was reduced.

The purpose of this study is to determine the stiffness of rubber of dynamic damper. This damper system reduces the steering wheel vibration caused by idling oscillation of the engine. Therefore, in order to measure the stiffness of the silicone rubber in the dynamic damper system, the material test of the silicone rubber was carried out. Using the measured stiffness, the FEM model of the dynamic damper system was constructed and the correlation by the experimental data was shown at an error of less than 2%. In addition, the dynamic damper system was simplified to a two-degree-of-freedom spring-mass model and the effect of the stiffness change of the rubber on the natural frequency of the column shaft was analyzed theoretically. As a result, the amplitude of the column shaft was reduced as the stiffness of the silicone rubber was lowered.