다물체 동역학을 이용한 기어 쌍의 전달오차 해석

Abstract

This research has developed two multibody gear models. One is the rigid body model and the other is the flexible body gear model. The flexible body gear model produces accurate results while the computation is very long. If many gear pairs exist in a system, the computation would grow significantly. In order to focus in reduce the computation time. Gear tooth is meshed into 8 node hexa solid elements. The mesh quality is very important to produce an accurate solution. Mesh size has been reduced so that the contact surface is smooth enough to produce a smooth contact force while a pair of gear teeth is mating. Only five gear teeth are meshed into solid elements and the rest part of the gear is left as a rigid body to reduce computation time. The gear body is allowed to rotate relative to the ground by a revolute joint. Flexible to flexible body contacts are defined to simulate the gear tooth contacts. Each gear tooth is modeled as a rigid body with a revolute joint and a rotational spring. Therefore, the gear tooth is allowed to have a relative rotation with respect to the gear shaft. The stiffness of the rotational spring accounts for the gear tooth compliance due to the flexibility of the gear tooth. Rigid to rigid contacts are defined to simulate the gear tooth contacts. This research is focused reduce calculate time so that the simplified rigid model produces the same results as these from the flexible body model.