Sebastian von Mammen

Design and exploration of braiding swarms in VR

Swarm-based braiding of structures represents a novel research direction in the domain of building architecture. The idea is that autonomous agents, for instance robots that unroll threads or plants that grow, are programmed or influenced to braid. It is an aspect of biohybrid systems where organisms and robots join forces. In order to harness this idea, we have developed a swarm-based model that allows architects to explore the resulting design spaces in virtual reality. In this paper, we present (1) the model of our swarm-based simulation that aims at growing braided structures, (2) the design elements to guide the otherwise self-organising virtual agents, and (3) the user interface that allows the user to configure, place and grow the swarms of braiding agents. We also present results of a first user study with students and faculty from architecture, in which we tried to capture the usability of our first prototype based on a survey and an analysis of the built results.

VReanimate — Non-verbal guidance and learning in virtual reality

First aid saves lives and reanimation is an important part of it. We developed a virtual reality (VR) application, VReanimate, that teaches about this aspect of first aid in a controlled digital environment. In this paper we present its non-verbal approach to guiding as many people as possible through the VR experience. In the first part of this paper, we describe the conceptual and implementational details of this approach that is based on showing ghost controllers and headsets to convey the necessary interfacing information in the virtual environment. These projected controllers and headsets were augmented with pictographic user feedback to direct and reinforce the users learnings. In the second part of this paper, we elaborate on our evaluation of the non-verbal approach to teaching first aid implemented by VReanimate. Conducting a qualitative study, we found that the non-verbal approach was able to impart knowledge to all testers. None of the participants had problems with the developed concepts and most of them understood the pictographic language without difficulties. Finally, the paper discusses the potential positive impact of the developed application VReanimate in real world first aid scenarios.

Rethinking real-time strategy games for virtual reality

Recent improvements in virtual reality (VR) technology promise the opportunity to redesign established game genres, such as real-time strategy (RTS) games. In this work we have a look at a taxonomy of RTS games and apply it to RTS titles for VR. Hereby, we identify possible difficulties such as the need for novel means of navigation in VR. We discuss conceivable solutions and illustrate them by referring to relevant work by others and by means of AStar0ID, an exploratory prototype VR RTS science fiction game. Our main contribution is the systematic inspection and discussion of foundational RTS aspects in the context of VR and, thus, to provide a substantial basis to further rethink and evolve the RTS genre in this new light.

Special issue on self-organised construction

This special issue of the Swarm Intelligence journal is a follow-up of the workshop on Self-Organising Construction, which was held in conjunction with the IEEE International Conference on Self-Adaptive and Self-Organizing Systems (SASO) in Augsburg, Germany, in September 2016. The workshop and this special issue bring a wide variety of methods and results from different fields together. They all aim at the same overarching goal: understanding, retracing and making self-organising construction processes technologically viable. The foundational biological perspective on the topic unearths insights about processes, such as nest constructions by social insects. Computer scientists translate and augment the biological principles to coordinated algorithms of collaboration. Engineers aim at providing the hardware platforms for robotic units which are able to transport and place construction materials. And there is the architectural perspective that explores how self-organised construction can complement and innovate established approaches to design, construction and even works of art. At the bottom of all these efforts lies the conceptual paradigm shift towards local interaction and local information in distributed systems: large numbers of individuals contribute to the construction process not by following a predefined plan but by sensing and reacting to stimuli in their local environment. Only carefully coordinated local actions allow for emerging global structures that show global patterns and have appropriate functions. Recently, with the wake of robotic swarms, self-organised construction is quickly gaining significance in the context of various design and construction processes.

The game of flow - cellular automaton-based fluid simulation for realtime interaction

In this paper, we present a realtime fluid simulation based on cellular automata (CAs). The main goal is to demonstrate the performance and extensibility of this approach. To show this, we created a fluid simulation and extended it by simulating different kinds of fluids at the same time with effects like oil foating on water and a focus on short computation time. This makes the simulation interesting for games in VR. In our simulation, we had a high framerate of 100 FPS for a CA running on the CPU with 1763 cells due to parallelization and optimization.

An evolutionary approach to behavioural morphometrics

In this short paper, we briefly outline the design of a new framework, BOODLE (BiOlOgical DeveLopment Environment), that empowers biologists to retrace developmental processes at the intercellular level. This framework allows one to import volumetric data as retrieved by micro-CT scanners. Meta-information such as labels of specific regions can be imported or annotated interactively in the virtual simulation environment. Consistently labelled series of multiple embryonic scans that have been recorded at different times capture developmental processes. In order to generate models to retrace the underlying dynamics, we deploy a Genetic Algorithm (GA). The GA optimises the parameters of physics-based virtual cells to retrace the captured processes in a simulation. In particular, the fitness of a set of parameters is calculated based on comparisons between the emerging geometric shapes and the real-world information. The real-world data is provided by said annotations or inferred from grey values captured by the CT scans. To support effective evolutionary optimisation, the user interface supports the user during the import and refinement of CT-data sets, the editing of landmarks, the popluating of imported volumetric data with virtual cells, and the configuration of the Genetic Algorithm.

3-D visualization of dynamic runtime structures

Continued development and maintenance of software requires understanding its design and behavior. Software at runtime creates a complex network of call--callee relationships that are hard to determine but that developers need to understand to optimize software performance. Existing tools typically focus on static aspects (e.g., Structure101 or SonarQube), or they are difficult to use and require high expertise (e.g., software profiling tools). Unfortunately, these dependencies are hard to derive from static code analysis: For one, static analysis will reveal potential call--callee relationships not actual ones. Second, they are often difficult to detect, since information systems today increasingly use abstraction patterns and code injection, which obscures runtime behavior. In this paper, we present our efforts towards accessible and informative means of visualizing software runtime processes. We designed a novel visualization approach that utilizes a hierarchical and interactive 3-D city layout based on force-directed graphs to display the runtime structure of an application. This promises to reduce the time and effort invested in debugging programming errors or in finding bottlenecks of software performance. Our approach extends the city metaphor for translating programmatic relationships into accessible 3D visualizations. With the identified goals and constraints in mind, we designed a novel visual debugging system, which maps programming code structures to 3D city layouts based on force-directed graphs. Exploration of the animated visualization allows the user to investigate not only the static relationships of large software projects but also its dynamic runtime behavior. We conducted a formative evaluation of the approach with a preliminary version of a prototype. In a series of six interviews with experts in software development and dynamic analysis, we were able to confirm that the approach is useful and supports identifying bottlenecks. The interviews raised and prioritized potential future improvements, several of which we implemented into the final version of our prototype.

A virtual reality simulation for children: Build and create from the perspective of a toy figure

Despite current (commercial) efforts to employ VR in educational and pedagogical contexts with children, the amount of topic-specific research leaves a lot to be desired. For example, no guidelines exist concerning the design or the application for this target group. Furthermore, there are no findings about health effects or potential benefits or issues. With this paper, we present an application, a toy brick construction simulation, which had the aim to adress some of these questions. The article describes the concept and first explorative evaluation, which was realized by conducting an expert interview with an experienced toy researcher. The presented findings should serve as hints concerning potential pedagogical benefits, effects and design aspects and be a basis for future studies with children. Furthermore, we hoped that they will incite discussion and promote research about the use of VR with young children.