Jan Riemann

ObjecTop: occlusion awareness of physical objects on interactive tabletops

In this paper, we address the challenges of occlusion created by physical objects on interactive tabletops. We contribute an integrated set of interaction techniques designed to cope with the physical occlusion problem as well as facilitate organizing objects in hybrid settings. These techniques are implemented in ObjecTop, a system to support tabletop display applications involving both physical and virtual objects. We compile design requirements for occlusion-aware tabletop systems and conduct the first in-depth user study comparing ObjecTop with conventional tabletop interfaces in search and layout tasks. The empirical results show that occlusion-aware techniques outperform the conventional tabletop interface. Furthermore, our findings indicate that physical properties of occluders dramatically influence which strategy users employ to cope with occlusion. We conclude with a set of design implications derived from the study.

Liquido: Embedding Liquids into 3D Printed Objects to Sense Tilting and Motion

Tilting and motion are widely used as interaction modalities in smart objects such as wearables and smart phones (e.g., to detect posture or shaking). They are often sensed with accelerometers. In this paper, we propose to embed liquids into 3D printed objects while printing to sense various tilting and motion interactions via capacitive sensing. This method reduces the assembly effort after printing and is a low-cost and easy-to-apply way of extending the input capabilities of 3D printed objects. We contribute two liquid sensing patterns and a practical printing process using a standard dual-extrusion 3D printer and commercially available materials. We validate the method by a series of evaluations and provide a set of interactive example applications.

StackTop: Hybrid Physical-Digital Stacking on Interactive Tabletops

The concurrent use of digital and physical documents on interactive surfaces is becoming more and more common. However, the integration of both document types is limited, one example being the ability to stack documents. In this paper we propose StackTop, an integrated system supporting ordered hybrid digital/physical piling (hybrid stacking) on interactive surfaces. This allows for a tighter physical/digital integration in hybrid workspaces and provides a more consistant approach when working with hybrid document sets.

BYO*: Utilizing 3D Printed Tangible Tools for Interaction on Interactive Surfaces

Sharing and manipulating information are essential for collaborative work in meeting scenarios. Nowadays, people tend to bring their own devices as a result of increasing mobility possibilities. However, transferring data from one device to another can be cumbersome and tedious if restrictions like different platforms, form factors or environmental limitations apply. In this paper, we present two concepts to enrich interaction on and between devices through 3D printed customized tangibles: 1) Bring your own information, and 2) bring your own tools. For this, we enable interactivity for low-cost and passive tangible 3D printed objects by adding conductive material and make use of touch-enabled surfaces. Our system allows users to easily share digital contents across various devices and to manipulate them with individually designed tools without additional hardware required.

FreeTop: Finding Free Spots for Projective Augmentation

Augmenting the physical world using projection technologies or head-worn displays becomes increasingly popular in research and commercial applications. However, a common problem is interference between the physical surfaces texture and the projection. In this paper, we present FreeTop, a combined approach to finding areas suitable for projection, which considers multiple aspects influencing projection quality, like visual texture and physical surface structure. FreeTop can be used in stationary and mobile settings for locating free areas in arbitrary physical settings suitable for projective augmentation and touch interaction.

In-Situ Occlusion Resolution for Hybrid Tabletop Environments

In this paper we explore the use of in situ occlusion resolution in mixed physical/digital tabletop scenarios. We propose the extension of back-projected tabletops with interactive top-projection to turn the physical object’s surface into peripheral displays. These displays are used to resolve occlusion in situ without the need to use additional tabletop display space and keeping the spatial perception of the occluded objects. We contribute a visualization concept and a set of interaction techniques for in situ occlusion resolution and easy access to occluded objects. The techniques are implemented in a system named ProjecTop, which is evaluated in an quantitative user study. The study results highlight how top-projection can be beneficially used. We conclude with a set of design implications derived from the study’s results.

PeriTop: extending back-projected tabletops with top-projected peripheral displays

Integrating digital tabletops into homes or desktop environments will give rise to a set of problems emerging from placing everyday objects on interactive tabletops. Chief among them is the arbitrary placement of physical objects that considerably limits the digital working space on the surface of tabletops. In this paper we contribute PeriTop, an interactive back-projected tabletop system which exploit the surface of physical objects and tabletop rims as additional interactive displays to represent and interact with digital objects. This is realized by augmenting the tabletop system with an inexpensive pico projector-depth camera pair. We support the PeriTop approach by depicting several salient use case scenarios aiding users in performing activities on hybrid physical-digital tabletop settings.

CheckMate: Exploring a Tangible Augmented Reality Interface for Remote Interaction

The digitalized world comes with increasing Internet capabilities, allowing to connect persons over distance easier than ever before. Video conferencing and similar online applications create great benefits bringing people who physically cannot spend as much time as they want virtually together. However, such remote experiences can also tend to lose the feeling of traditional experiences. People lack direct visual presence and no haptic feedback is available. In this paper, we tackle this problem by introducing our system called CheckMate. We combine Augmented Reality and capacitive 3D printed objects that can be sensed on an interactive surface to enable remote interaction while providing the same tangible experience as in co-located scenarios. As a proof-of-concept, we implemented a sample application based on the traditional chess game.

FlowPut: Environment-Aware Interactivity for Tangible 3D Objects

Tangible interaction has shown to be beneficial in a wide variety of scenarios since it provides more direct manipulation and haptic feedback. Further, inherently three-dimensional information is represented more naturally by a 3D object than by a flat picture on a screen. Yet, todays tangibles have often pre-defined form factors and limited input and output facilities. To overcome this issue, the combination of projection and depth cameras is used as a fast and flexible way of non-intrusively adding input and output to tangibles. However, tangibles are often quite small and hence the space for output and interaction on their surface is limited. Therefore, we propose FlowPut: an environment-aware framework that utilizes the space available on and around a tangible object for projected visual output. By means of an optimization-based layout approach, FlowPut considers the environment of the objects to avoid interference between projection and real-world objects. Moreover, we contribute an occlusion resilient object recognition and tracking for tangible objects based on their 3D model and a point-cloud based multi-touch detection, that allows sensing touches also on the side of a tangible. Flowput is validated through a series of technical experiments, a user study, and two example applications.

An Evaluation of Hybrid Stacking on Interactive Tabletops

Stacking is a common practice of organizing documents in the physical world. With the recent advent of interactive tabletops, physical documents can now coexist with digital documents on the same surface. As a result, systems were developed and studied which allow piling of both types of documents with the physical documents being placed on top of the digital ones. In this paper, we study the concept of true hybrid stacking, allowing users to stack both types of documents in an arbitrary order using a hybrid tabletop system called StackTop. We discuss the results and derive implications for future hybrid tabletop systems with stacking support.