Holger Graf

The Common Implementation Framework as Service Towards Novel Applications for Streamlined Presentation of 3D Content on the Web

We solve a standing issue of the recently published Common Implementation Framework (CIF) for Online Virtual Museums: programmatic access to the transcoding, optimization and template rendering infrastructure of the CIF. We propose a method that enables researchers and developers to build novel systems on top of the CIF infrastructure beyond its current Cultural Heritage workflow. Therefore, we introduce a way to programmatically access the powerful backend of the CIF through a universal access layer, addressable by standards like HTTP and the JSON Data Interchange Format. In order to demonstrate our approach, we present two different use cases in which the CIF pipeline is utilized as a service through the proposed resource-based access layer: a native mobile iOS application for browsing 3D model repositories realizing just-in-time optimization of large models, and a MeshLab plugin to asynchronously convert and prepare a model for the Web.

Beyond 3D "As-Built" Information Using Mobile AR Enhancing the Building Lifecycle Management

The success of smart phone technologies changed the way information is processed as more and more geo-referenced structures are emerging linking information to specific locations within our environment. Thereby, Augmented Reality has become a key technology as it analyses the smart phone sensor data (camera, GPS, inertial) to derive the detailed pose of the smart phone, with the aim to correlate our real environment to the geo-referenced information space. In particular, this is relevant for application fields where 3Dmodels are used in planning and organization processes as e.g. facility management. In facility construction and management Building Information Model (BIM) was established as a standard that not only holds the 3D-building-geometry but encompasses pipe/electrical systems as well as semantic building information, for example properties and conditions of building components. With this motivation our work integrates BIM and Augmented Reality.

Real-time 3D reconstruction and pose estimation for human motion analysis

In this paper, we present a markerless 3D motion capture system based on a volume reconstruction technique of non rigid bodies. It depicts a new approach for pose estimation in order to fit an articulated body model into the captured real-time information. We aim at analyzing athletes movements in real-time within a 3D interactive graphics system. The paper addresses recent trends in vision based analysis and its fusion with 3D interactive computer graphics. Hence, the proposed system presents new methods for the 3D reconstruction of human body parts from calibrated multiple cameras based on voxel carving techniques and a 3D pose estimation methodology using Pseudo-Zernike Moments applied to an articulated human body model. Several algorithms have been designed for the deployment within a GPGPU environment allowing us to calculate several principle process steps from segmentation and reconstruction to volume optimization in real-time.

Mesh deformations in X3D via CUDA with freeform deformation lattices

In this paper we present a GPU-accelerated implementation of the well-known freeform deformation algorithm to allow for deformable objects within fully interactive virtual environments. We furthermore outline how our real-time deformation approach can be integrated into the X3D standard for more accessibility of the proposed methods. The presented technique can be used to deform complex detailed geometries without pre-processing the mesh by simply generating a lattice around the model. The local deformation is then computed for this lattice instead of the complex geometry, which efficiently can be carried out on the GPU using CUDA.

Towards a common implementation framework for online virtual museums

We present a prototypical solution to a common problem in the Cultural Heritage (CH) domain. After creation, 3D models of CH artifacts need to be processed to a format suitable for presentation on multiple platforms, e.g. in a Web Browser for online virtual museum applications, to target desktop computers and mobile devices alike. The constraints of an in-browser presentation give rise to a series of optimization and conversion concerns that need to be addressed to successfully display the CH objects in a Web application. Current 3D authoring tools do not readily support this kind of optimization and conversion required for CH domain scenarios. We therefore propose a web-based service framework, which solves the problem of pipelining 3D models for interactive Web presentations. We apply open-source technologies like X3DOM, Flask, Celery, and Redis to create a Common Implementation Framework (CIF) that allows content designers or researchers to optimize their 3D models for the Web through a simple one-step process.

Linear Static, Real-Time Finite Element Computations Based on Element Masks

This paper presents a new method for the manipulation of a given CAE domain in view of VR based explorations that enables engineers to interactively inspect and analyze a linear static domain. The interactions can ideally be performed in real-time in order to provide an intuitive impression of the changes to the underlying volumetric domain. We take the approach of element masking, i.e. the blending out of computations resulting from computational overhead for inner nodes, based on the inversion of the stiffness matrix. This allows us to optimize the re-simulation loop and to achieve real-time performance for strain and stress distributions with immediate visualization feedback caused by interactively changing boundary conditions. The novelty of the presented approach is a direct coupling of view dependent simulations and its close linkage to post-processing tasks. This allows engineers to also inspect the changes of the stress field inside of the volume during, e.g. cross sectioning.

Virtual Reality Based Interactive Conceptual Simulations

This paper presents a new approach for the design and realization of a Virtual Reality (VR) based engineering front end that enables engineers to combine post processing tasks and finite element methods for linear static analyses at interactive rates. “What-if-scenarios” have become a widespread methodology in the CAE domain. Here, designers and engineers interact with the virtual mock-up, change boundary conditions (BC), variate geometry or BCs and simulate and analyze its impact on the CAE mock-up. The potential of VR for post-processing engineering data enlightened ideas to deploy it for interactive investigations at conceptual stage. While it is a valid hypothesis, still many challenges and problems remain due to the nature of the “change’n play” paradigm imposed by conceptual simulations as well as the non-availability of accurate, interactive FEM procedures. Interactive conceptual simulations (ICS) require new FEM approaches in order to expose the benefit of VR based front ends.

Muntermacher - think and move interface and interaction design of a motion-based serious game for the generation plus

This paper presents a holistic approach to design a media system based on a new user interface and interaction device aimed to motivate seniors of the generation plus enhancing their daily physical activity. As a result of the newly designed game, the senior finds himself within a colorful world of a game in which he interacts with small lively figures using a newly designed interaction device accounting for physical activity. The combination of both design elements, lead to a gameplay that provides adequate mechanism for cognitive and physical activity, challenging representatives of the generation plus to exercise more.

Accelerated real-time reconstruction of 3D deformable objects from multi-view video channels

In this paper we present a new framework for an accelerated 3D reconstruction of deformable objects within a multi-view setup. It is based on a new memory management and an enhanced algorithm pipeline of the well known Image-Based Visual Hull (IBVH) algorithm that enables efficient and fast reconstruction results and opens up new perspectives for the scalability of time consuming computations within larger camera environments. As a result, a significant increase of frame rates for the volumetric reconstruction of deformable objects can be achieved using an optimized CUDA-based implementation on NVIDIAs Fermi-GPUs.

Virtual Reality Based Space Operations – A Study of ESA’s Potential for VR Based Training and Simulation

This paper presents the results of a study the authors conducted together over a year in order to identify key issues of ESA’s (European Space Agency) potential for a deployment of Virtual Reality training environments within space operations. Typically, ESA simulates several operations using DES like systems that need to be linked to a VR environment for training purposes. Based on the second generation of VR equipment and development tools the paper describes a holistic design approach from scenario development through design decisions on SW and HW choices until the final development of a PoC for a virtual lunar base that might simulate the metabolism of a lunar base. Here the idea was to mirror the mass- and energy-flows within a lunar base in order to maintain an environment, in which astronauts can live and work and to establish a tool that supports the training of astronauts for operating such a lunar base, the one likely next step of human space exploration beyond the International Space Station as identified by ESAs decision makers. In the end, we have realized a PoC for a fire emergency case on a lunar base allowing astronauts being trained in a fully simulated and integrated environment. The system could be tested and evaluated in two set-ups, first using classical VR controllers, second, using recent VR glove technology.