Determining the optimal build directions in layered manufacturing

Determining the optimal build directions is one of the most critical factors in RP processes because it affects on the build time, support structure, surface quality as well as the cost. The previous methods could handle simple parts or limited objective functions. Moreover the methods with multiple objective functions, had abstracted them into a single fitness function in which the characteristics of individual objectives could not be reflected properly. In the present work a new algorithm is presented to determine the optimal build-up directions of the part in Stereolithography systems. The algorithm can help RP users select among the optimal build-up directions.The optimization is done using Multi-Objective Genetic Algorithm (MOGA). The method proposed here handles build time, support volume and surface finish as objective functions individually. At each GA step, the surface finish is achieved applying adaptive layer thickness method and optimization algorithm finds the optimal build directions with minimum build time and volume support. The algorithm is developed by MATLAB. To evaluate the algorithm, several sample parts are checked. Key-Words: StereolithographyOptimal Build DirectionMulti Objective Optimization Genetic Algorithm