A global collaborative design framework for sketch-based parametric CAD modelling

Despite that paper-based freehand sketching is still widely used during the conceptual design phase, few are the tools available that allow designers to exploit sketches resulting from this activity at a later design phase. This paper reports the ongoing research on a prototype tool nicknamed mX-Sketch, which addresses this lack of support by linking freehand paper-based sketches with Computer-Aided Design (CAD) technology. Given that paper-based sketching is also used by designers outside their office to express their ideas, the rapid transfer and automatic generation of 3D virtual models from such sketches provide real-time design collaboration. Since a paper-based freehand sketch is inherently vague, the 3D form idea is clarified by means of symbols representing 2D geometric constraints (e.g. perpendicularity). As a result, mX-Sketch produces a parametric 3D virtual model, which can be potentially used downstream in the design process and exchanged in real time in collaborative design scenarios.