Winner of the “All-Conference Best paper of ASME IDETC/CIE 2012” award
Abstract: We present the paradigm of natural and exploratory shape modeling by introducing novel 3D interactions for creating, modifying and manipulating 3D shapes using arms and hands. Though current design tools provide complex modeling functionality, they remain non-intuitive and require significant training since they segregate 3D shapes into hierarchical 2D inputs, thus binding the user to stringent procedural steps and making modifications cumbersome. In addition the designer knows what to design when they go to CAD systems and the creative exploration in design is lost. We present a shape creation paradigm as an exploration of creative imagination and externalization of shapes, particularly in the early phases of design. We integrate the capability of humans to express 3D shapes via hand-arm motions with traditional sweep surface representation to demonstrate rapid exploration of a rich variety of fairly complex 3D shapes. We track the skeleton of users using the depth data provided by low cost depth sensing camera (Kinect). Our modeling tool is configurable to provide a variety of implicit constraints for shape symmetry and resolution based on the position, orientation and speed of the arms. Intuitive strategies for coarse and fine shape modifications are also proposed. We conclusively demonstrate the creation of a wide variety of product concepts and show an average modeling time of a only few seconds while retaining the intuitiveness of communicating the design intent.