User Defined Conceptual Modeling Gestures Bige Tunçer and Sumbul Khan Abstract Gesture and speech based interaction offers designers a powerful tech- nique to create 3D CAD models. Previous studies on gesture based modeling have employed author defined gestures which may not be very user friendly. The aim of this study was to collect a data set of user generated gestures and accompanying voice commands for 3D modeling for form exploration in the conceptual architectural design phase. We conducted an experiment with 41 subjects to elicit their preferences in using gestures and speech for twelve 3D CAD modeling referents. In this paper we present the different types of gestures we found, and present user preferences of gestures and speech. Findings from this study will be used for the design of a speech and gesture based Cad modeling interface. Keywords Conceptual architectural design · Gesture based modeling · Natural user interface · Gesture studies · Human computer interaction 1 Introduction This research aims to address the issue of computer support during the conceptual design stage, when problems are ill-defined and designers formulate the initial param- eters for an artifact [1]. Conventional CAD systems use graphical user interfaces that rely on input devices such as mouse and keyboard, which are seen to constrain human-computer dialogue [2]. Gesture and speech based interaction offers a natural and flexible interaction technique for designers for 3D modeling during conceptual B. Tunçer (B ) Architecture and Sustainable Design, Singapore University of Technology and Design, Singapore, Singapore e-mail: bige_tuncer@sutd.edu.sg S. Khan SUTD-MIT International Design Centre, Singapore University of Technology and Design, Singapore, Singapore e-mail: sumbul_khan@sutd.edu.sg © Springer Nature Singapore Pte Ltd. 2018 J.-H. Lee (ed.), Computational Studies on Cultural Variation and Heredity, KAIST Research Series, https://doi.org/10.1007/978-981-10-8189-7_10 115