Free Form Surface Skinning of 3D Curve Clouds for Conceptual Shape Design

Abstract

In product design, designers often create a multitude of concept sketches as part of the ideation and exploration process. Transforming such sketches to 3D digital models requires special expertise due to a lack of intuitive computer aided design (CAD) tools suitable for rapid modeling. Recent advances in sketch-based user interfaces and immersive environments have introduced novel curve design methods that facilitate the transformation of such sketches into 3D digital models. However, rapid surfacing of such data remains an open challenge. Based on the observation that a sparse network of curves is reasonably sufficient to convey the intended geometric shape, we propose a new method for creating approximate surfaces on curve clouds automatically. A notable property of our method is that it relieves many topological and geometric restrictions of 3D conventional networks such as the curves do not need to be connected to one another or gently drawn. Our method calculates a 3D guidance vector field in the space that the curve cloud appears. This guidance vector field helps drive a deformable closed surface onto the curves. During this deformation, surface smoothness is controlled through a set of surface smoothing and subdivision operations. The resulting surface can be further beautified by the user manually using selective surface modification and fairing operations. We demonstrate the effectiveness of our approach on several case examples. Our studies have shown that the proposed technique can be particularly useful for rapid visualization.

Strokes2Surface: Recovering Curve Networks From 4D Architectural Design Sketches

“…Their specialized surfacing algorithm, coupled with their sketching interface, works by converting raw designer‐drawn strokes into a user‐intended manifold 3D surface by matching edge sequences along input stroke polylines. [BAOBK12] surfaces sparse and imprecise 3D sketches by smoothly deforming an initial low‐fidelity surface of correct topology, using a discrete guidance vector field that points towards the closest stroke point. This approach produces globally smooth surfaces but requires user intervention to specify strokes that should be inserted into the mesh as sharp edge polylines.…”

“…Surfacing Stroke Clouds . In the computer graphics and vision community, a few methods have been proposed to reconstruct 3D geometries from stroke clouds [FK10, BAOBK12, YAB*22, LCX*23]. Relying on the images from coarsely calibrated cameras, [FK10] developed a framework for 3D reconstruction from an unorganized set of curves.…”

BCI-Touch Based System: A Multimodal CAD Interface for Object Manipulation

“…Kara et al presented a study related to the surface skinning of 3D curve clouds drawn in a free form for conceptual shape design [5]. Their method takes into account scattered geometrical and topological data to produce an approximate surface by connecting the curve clouds which are in the form of 3D sketches.…”

“…Their method takes into account scattered geometrical and topological data to produce an approximate surface by connecting the curve clouds which are in the form of 3D sketches. They use a guidance vector field calculated from the input curve clouds to bridge the gap between them and induce a surface without altering any of the geometrical or topological information [5]. Research has also been done to incorporate augmented reality environments with CAD packages for the creation and modification of free form surfaces through 3D sketch-based inputs [6].…”