A Novel Approach for Conceptual Structural Design of Gearbox

The paper presents a novel approach for conceptual structural design of a complex machine part. The approach consists of the following four steps: (i) building a geometric-physical model, (ii) extracting a conceptual model, (iii) meeting the strength and stiffness requirements, and (iv) considering structural manufacturability and aesthetics. Due to the design constraints of a complex machine part in both geometrical and physical requirements, a geometric model is built as a simple geometric shape including all connection surfaces. And a physical model is a finite element model with loads and connection constraints incorporated. The conceptual model is a truss structure in accordance with the material distribution and load paths under different load cases. During designing conceptual structure, its skeleton is accomplished according to the optimal material distribution. The dimensions of the structural skeleton are determined based on the required structural strength and stiffness. Finally, by taking into account the manufacturability and aesthetic appearance, a conceptual structure with the required dimensions is accepted as the actual structure of the machine part. Using a gearbox design as an illustrative example, we demonstrated that the proposed approach is efficient and reliable. The new conceptual structure, produced using this approach for a gearbox, is superior to the empirical and analogical approaches because of lack of proven and reliable design methodology in the literature.