Process design for micromilling of stochastically distributed bionic surface structures

The process design for the manufacturing of surface structures with functional tribological properties is a major challenge when machining workpieces with freeform surfaces. Distortion effects of the structures and limitation of CAD/CAM-systems require the development of novel technological solutions. The paper presents a new approach for designing the machining processes of functional textures on freeform surfaces. Within the approach, a new bionic motivated type of micromilled surface structures is presented. By stochastically distributing sampling points for the replication of machining commands of individual structure elements, a stochastic surface structure can be produced while simplifying the process design. In this paper, the procedure for generating NC paths on the free-form surfaces of using Poisson-Disk sampling as well as transferring this to a machine-compatible machining program is illustrated. The basic approach as well as the resulting surface structures are further compared with the method of NC-projection and the potentials of the new approach are discussed.