This research aimed to reduce the amount of material in an exocalf. The calf was to be made lighter for fabrication while maintaining the same amount of strength. nTop was used for the simulation and light-weighting.

Lattice structures were used for light-weighting as they are efficient in reducing excess mass while maintaining the overall strength of the part. Field were used to vary the thickness of the lattice

To drive the optimization, a static analysis was first performed, two fixed restraints were done on the bottom and front of the calf, as well as a force on the motor holder side of the calf, and a counter moment on the front of the calf.  

The material set for the static study was TPU 90A Powder.

Using the same boundary conditions as with the static analysis, a topology optimization was done on the calf, with the goal of removing any excess mass using a stress response and volume fraction response. 

Areas in which there are no material indicate regions of minimal stress so we can expect a thin lattice structure. 

Using the density scalar field from the topology optimization, a voronoi volume lattice can be created such that the lattice is thicker based on regions of higher stress. 

Using the created Voronoi Volume lattice, boolean intersections can be made with the original calf part to trim any excess lattice, and intersections can be made with regions we need (mounts) for a finalized part. 

Using the mass properties feature, it was seen that the weight of the calf was reduced by 58.63 %