Optimization of the Cantilever Beam with TPMS Lattice Structure

Abstract

The topology optimization has been presented in the example of a gyroid cantilever beam with a rectangular cross-section by using the software nTopology. The accuracy of the numerical model was checked by analytical solution, and by measuring strain in the printed beam. The direct integration method has been used to calculate deflection with the variation of the moment of inertia along the beam's axial axis. The corresponding stress and strain values were also calculated and compared with the numerical ones. The values are much lower since the effect of stress concentration has not been considered in analytical solutions. Experimental analysis by measuring strain with strain gauges on a 3D-printed beam was made to confirm the results. In the next step it was determined that the diamond type fits best according to the results of maximum deflection from the chosen three TPMS lattice structures. To optimize the topology of the beam, the thickness of the diamond cell was used as a parameter. The goal was to strengthen the structure by increasing the wall thickness of cells in the places where the beam has higher elastic stress values to get better stress distribution. The mass was additionally reduced by 16.35%.

Keywords

• cantilever beam
• lattice structure
• nTopology
• structural optimization