Micro-scale feature fabrication using immersed surface accumulation

Most additive manufacturing (AM) processes such as stereolithography (SLA) and selective laser sintering (SLS) use a layer-by-layer fabrication approach. They cannot be used to fabricate geometric features on the surfaces of a pre-existing three-dimensional (3D) object. In addition, existing AM processes are mainly based on a single size scale, e.g. macro-scale or micro-scale, and cannot be used to build a macro-scale object with micro-scale features on its surfaces. In this paper, we present a novel immersed surface accumulation process that can fabricate micro-scale features on macro-scale surfaces. In the process, a surface-based light guide tool is immersed inside liquid resin to fabricate high-resolution features on the surfaces of a pre-existing object. The system design and process settings to fabricate 3D features are presented. The relation between process control and related fabrication property is discussed. Two test cases are presented to demonstrate the effectiveness of the newly developed immersed surface accumulation process.