Vinayak and Karthik Ramani
A Gesture-free Geometric Approach for Mid-Air Expression of Design Intent
Computer-Aided Design (Elsevier), Available online 17 July 2015, ISSN 0010-4485,

Abstract: The advent of depth cameras has enabled mid-air interactions for shape modeling with bare hands. Typically, these interactions employ a finite set of pre-defined hand gestures to allow users to specify modeling operations in virtual space. However, human interactions in real world shaping processes (such as pottery or sculpting) are complex, iterative and continuous. In this paper, we show that the expression of user intent in shaping processes can be derived from the geometry of contact between the hand and the manipulated object. Specifically, we describe the design and evaluation of a geometric interaction technique for bare-hand mid-air virtual pottery. We model the shaping of a pot as a gradual and progressive convergence of the pot-profile to the shape of the user’s hand represented as a point-cloud (PCL). Thus, a user does not need to learn, know or remember any gestures to interact with our system. Our choice of pottery simplifies the geometric representation allowing us to systematically study how users use their hands and fingers to express the intent of deformation during a shaping process. Our evaluations demonstrate that it is possible to enable users to express their intent for shape deformation without the need for a fixed set of gestures for clutching and deforming a shape.

Proximal Persistence

About Vinayak

Vinayak received his Ph.D. in Mechanical Engineering from Purdue University in December 2015. The central theme of his research is the expression of design intent towards supporting early phase idea generation for product form exploration. During his Ph.D. at the C-Design Lab, he investigated symbolic and geometric interpretations of hand gestures, hand grasp, and arm movements for mid-air shape conceptualization. He extended these ideas to the tangible interactions for quick design ideation using hand-held mobile devices. Currently, he is a post-doctoral scholar in the School of Mechanical Engineering at Purdue University where he continues working at the C-Design Lab. His current research involves building systems for collaborative design using mobile technology.


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Posted in 2015, HUMAN SHAPE INTERACTION, Karthik Ramani, Mid-air Interaction, Vinayak