Developing Digital Media Platforms for Early Design

In recent times, mobile devices are becoming an integral part of our daily life. Software applications on these handheld devices are successfully migrating the traditional paper-based activities such as reading news, books, and even navigating through maps, onto the digital medium. While these applications allow information access anywhere and anytime, there is still a necessity for repurposing these digital media to support content/information creation especially in domains such as industrial design where paper-based activities are common. To utilize direct-touch tablets for collaborative conceptual design, we studied their affordances and iteratively developed a web-based wiki system, named skWiki. In this thesis, we first report an evaluation of the impact of utilizing a capacitive stylus for tracing and sketching on direct-touch tablets. This study uncovers the differences in quantitative and qualitative performance of the tablet medium compared to the paper medium when using a stylus (pen) or finger input for both tracing and sketching. While paper performed better overall, we found that the tablet medium, when used with a capacitive stylus, performed comparably to the paper medium for sketching tasks. These findings can guide sketch application designers in developing an appropriate interaction design for various input methods. In order to explore the advantages of the ubiquity of information generated on digital media, we developed Sketchbox, an Android application for sketching and sharing ideas using Dropbox as the storage cloud. An evaluation of the usage patterns of this application in a collaborative toy design scenario provided necessary guidelines for developing the skWiki system. skWiki overcomes the drawbacks of traditional wiki software, that are used as design repositories, by providing a rich editor infrastructure for sketching, text editing, and image editing. Apart from these features, skWiki provides a higher degree of freedom in sharing (cloning, branching, and merging) different versions of a sketch at various data granularities by introducing the concept of paths for maintaining revisions in a collaborative design process. We evaluated the utility of skWiki through a user study by comparing constrained and unconstrained sharing models. Furthermore, skWiki was used by the students of toy design and product design courses for both collaborative ideation and design activities. We discuss the findings and qualitative feedback from the evaluation of skWiki, and potential features for the next version of this tool

Freeform User Interfaces for Graphical Computing

報告番号: 甲15222 ; 学位授与年月日: 2000-03-29 ; 学位の種別: 課程博士 ; 学位の種類: 博士(工学) ; 学位記番号: 博工第4717号 ; 研究科・専攻: 工学系研究科情報工学専

Barehand Mode Switching in Touch and Mid-Air Interfaces

Raskin defines a mode as a distinct setting within an interface where the same user input will produce results different to those it would produce in other settings. Most interfaces have multiple modes in which input is mapped to different actions, and, mode-switching is simply the transition from one mode to another. In touch interfaces, the current mode can change how a single touch is interpreted: for example, it could draw a line, pan the canvas, select a shape, or enter a command. In Virtual Reality (VR), a hand gesture-based 3D modelling application may have different modes for object creation, selection, and transformation. Depending on the mode, the movement of the hand is interpreted differently. However, one of the crucial factors determining the effectiveness of an interface is user productivity. Mode-switching time of different input techniques, either in a touch interface or in a mid-air interface, affects user productivity. Moreover, when touch and mid-air interfaces like VR are combined, making informed decisions pertaining to the mode assignment gets even more complicated. This thesis provides an empirical investigation to characterize the mode switching phenomenon in barehand touch-based and mid-air interfaces. It explores the potential of using these input spaces together for a productivity application in VR. And, it concludes with a step towards defining and evaluating the multi-faceted mode concept, its characteristics and its utility, when designing user interfaces more generally

Video interaction using pen-based technology

Dissertação para obtenção do Grau de Doutor em InformáticaVideo can be considered one of the most complete and complex media and its manipulating is still a difficult and tedious task. This research applies pen-based technology to video manipulation, with the goal to improve this interaction. Even though the human familiarity with pen-based devices, how they can be used on video interaction, in order to improve it, making it more natural and at the same time fostering the user’s creativity is an open question. Two types of interaction with video were considered in this work: video annotation and video editing. Each interaction type allows the study of one of the interaction modes of using pen-based technology: indirectly, through digital ink, or directly, trough pen gestures or pressure. This research contributes with two approaches for pen-based video interaction: pen-based video annotations and video as ink. The first uses pen-based annotations combined with motion tracking algorithms, in order to augment video content with sketches or handwritten notes. It aims to study how pen-based technology can be used to annotate a moving objects and how to maintain the association between a pen-based annotations and the annotated moving object The second concept replaces digital ink by video content, studding how pen gestures and pressure can be used on video editing and what kind of changes are needed in the interface, in order to provide a more familiar and creative interaction in this usage context.This work was partially funded by the UTAustin-Portugal, Digital Media, Program (Ph.D. grant: SFRH/BD/42662/2007 - FCT/MCTES); by the HP Technology for Teaching Grant Initiative 2006; by the project "TKB - A Transmedia Knowledge Base for contemporary dance" (PTDC/EAT/AVP/098220/2008 funded by FCT/MCTES); and by CITI/DI/FCT/UNL (PEst-OE/EEI/UI0527/2011