SHAPE OPTIMIZATION OF SPACE TRUSSES SUBJECT TO FREQUENCY CONSTRAINTS

An evolutionary node shift method is presented for shape (geometry) optimization of a space truss structure with several frequency constraints. Coordinates of nodes or joints are regarded as design variables in the process. By means of design sensitivity analysis, the nodal efficiency or sensitivity number is first defined, and the most efficient nodes are identified and shifted in priority. The optimal solution is achieved gradually with a minimum weight increment. Kuhn-Tucker optimality conditions are then used to examine the obtained result to ensure weight minimization. Finally, two typical trusses are employed to demonstrate the feasibility and effectiveness of the method.