arXiv subjects

Felix G. Hamza-Lup

Publications and source records attributed to Felix G. Hamza-Lup.

31 records · Page 2Linked to original sources

arXiv2018

Scene Synchronization for Real-Time Interaction in Distributed Mixed Reality and Virtual Reality Environments

Advances in computer networks and rendering systems facilitate the creation of distributed collaborative environments in which the distribution of information at remote locations allows efficient communication. One of the challenges in networked virtual environments is maintaining a consistent view of the shared state in the presence of inevitable network latency and jitter. A consistent view in a shared scene may significantly increase the sense of presence among participants and facilitate their interactivity. The dynamic shared state is directly affected by the frequency of actions applied on the objects in the scene. Mixed Reality (MR) and Virtual Reality (VR) environments contain several types of action producers including human users, a wide range of electronic motion sensors, and haptic devices. In this paper, the authors propose a novel criterion for categorization of distributed MR/VR systems and present an adaptive synchronization algorithm for distributed MR/VR collaborative environments. In spite of significant network latency, results show that for low levels of update frequencies the dynamic shared state can be maintained consistent at multiple remotely located sites.

cs.NI↗

arXiv2018

Medical Simulation and Training: "Haptic" Liver

Tactile perception plays an important role in medical simulation and training, specifically in surgery. The surgeon must feel organic tissue hardness, evaluate anatomical structures, measure tissue properties, and apply appropriate force control actions for safe tissue manipulation. Development of novel cost effective haptic-based simulators and their introduction in the minimally invasive surgery learning cycle can absorb the learning curve for residents. Receiving pre-training in a core set of surgical skills can reduce skill acquisition time and risks. We present the development of a cost-effective visuo-haptic simulator for the liver tissue, designed to improve practice-based education in minimally invasive surgery. Such systems can positively affect the next generations of learners by enhancing their knowledge in connection with real-life situations while they train in mandatory safe conditions.

cs.HC↗

arXiv2018

The haptic paradigm in education: Challenges and case studies

The process of learning involves interaction with the learning environment through our five senses (sight, hearing, touch, smell, and taste). Until recently, distance education focused only on the first two of those senses, sight and sound. Internet-based learning environments are predominantly visual with auditory components. With the advent of haptic technology we can now simulate/generate forces and, as a result, the sense of touch. The gaming industry has promoted the "touch" on the "wire", allowing complex multi-modal interactions online. In this article we provide a brief overview of the evolution of haptic technology, its potential for education, and existing challenges. We review recent data on 21st century students' behaviors, and share our experiences in designing interactive haptic environments for education. From the "Community of Inquiry" framework perspective, we discuss the potential impact of haptic feedback on cognitive and social presence.

cs.HC↗

arXiv2018

Distributed Augmented Reality with 3D Lung Dynamics -- A Planning Tool Concept

Augmented Reality (AR) systems add visual information to the world by using advanced display techniques. The advances in miniaturization and reduced costs make some of these systems feasible for applications in a wide set of fields. We present a potential component of the cyber infrastructure for the operating room of the future; a distributed AR based software-hardware system that allows real-time visualization of 3D lung dynamics superimposed directly on the patient's body. Several emergency events (e.g. closed and tension pneumothorax) and surgical procedures related to the lung (e.g. lung transplantation, lung volume reduction surgery, surgical treatment of lung infections, lung cancer surgery) could benefit from the proposed prototype.

cs.DC↗

arXiv2018

Sensors in Distributed Mixed Reality Environments

With the advances in sensors and computer networks an increased number of Mixed Reality (MR) applications require large amounts of information from the real world. Such information is collected through sensors (e.g. position and orientation tracking sensors). These sensors collect data from the physical environment in real-time at different locations and a distributed system connecting them must assure data distribution among collaborative sites at interactive speeds. We propose a new architecture for sensor based interactive distributed environments that falls in-between the atomistic peer-to-peer model and the traditional client-server model. Each node in the system is autonomous and fully manages its resources and connectivity. The dynamic behavior of the nodes is triggered by the human participants that manipulate the sensors attached to the nodes.

cs.NI↗

arXiv2018

A Distributed Augmented Reality System for Medical Training and Simulation

Augmented Reality (AR) systems describe the class of systems that use computers to overlay virtual information on the real world. AR environments allow the development of promising tools in several application domains. In medical training and simulation the learning potential of AR is significantly amplified by the capability of the system to present 3D medical models in real-time at remote locations. Furthermore the simulation applicability is broadened by the use of real-time deformable medical models. This work presents a distributed medical training prototype designed to train medical practitioners' hand-eye coordination when performing endotracheal intubations. The system we present accomplishes this task with the help of AR paradigms. An extension of this prototype to medical simulations by employing deformable medical models is possible. The shared state maintenance of the collaborative AR environment is assured through a novel adaptive synchronization algorithm (ASA) that increases the sense of presence among participants and facilitates their interactivity in spite of infrastructure delays. The system will allow paramedics, pre-hospital personnel, and students to practice their skills without touching a real patient and will provide them with the visual feedback they could not otherwise obtain. Such a distributed AR training tool has the potential to: allow an instructor to simultaneously train local and remotely located students and, allow students to actually "see" the internal anatomy and therefore better understand their actions on a human patient simulator (HPS).

cs.DC↗

arXiv2018

Online External Beam Radiation Treatment Simulator

Radiation therapy is an effective and widely accepted form of treatment for many types of cancer that requires extensive computerized planning. Unfortunately, current treatment planning systems have limited or no visual aid that combines patient volumetric models extracted from patient-specific CT data with the treatment device geometry in a 3D interactive simulation. We illustrate the potential of 3D simulation in radiation therapy with a web-based interactive system that combines novel standards and technologies. We discuss related research efforts in this area and present in detail several components of the simulator. An objective assessment of the accuracy of the simulator and a usability study prove the potential of such a system for simulation and training.

cs.GR↗

arXiv2018

Interactive X-ray and proton therapy training and simulation

External beam X-ray therapy (XRT) and proton therapy (PT) are effective and widely accepted forms of treatment for many types of cancer. However, the procedures require extensive computerized planning. Current planning systems for both XRT and PT have insufficient visual aid to combine real patient data with the treatment device geometry to account for unforeseen collisions among system components and the patient. We are proposing a cost-effective method to extract patient specific S-reps in real time, and combine them with the treatment system geometry to provide a comprehensive simulation of the XRT/PT treatment room. The X3D standard is used to implement and deploy the simulator on the web, enabling its use not only for remote specialists' collaboration, simulation, and training, but also for patient education.

cs.GR↗

arXiv2018

Beyond the Desktop: Emerging Technologies for Supporting 3D Collaborative Teams

The emergence of several trends, including the increased availability of wireless networks, miniaturization of electronics and sensing technologies, and novel input and output devices, is creating a demand for integrated, full-time displays for use across a wide range of applications, including collaborative environments. In this paper, we present and discuss emerging visualization methods we are developing particularly as they relate to deployable displays and displays worn on the body to support mobile users.

cs.HC↗

arXiv2018

Generating Classes of 3D Virtual Mandibles for AR-Based Medical Simulation

Simulation and modeling represent promising tools for several application domains from engineering to forensic science and medicine. Advances in 3D imaging technology convey paradigms such as augmented reality (AR) and mixed reality inside promising simulation tools for the training industry. Motivated by the requirement for superimposing anatomically correct 3D models on a Human Patient Simulator (HPS) and visualizing them in an AR environment, the purpose of this research effort is to derive method for scaling a source human mandible to a target human mandible. Results show that, given a distance between two same landmarks on two different mandibles, a relative scaling factor may be computed. Using this scaling factor, results show that a 3D virtual mandible model can be made morphometrically equivalent to a real target-specific mandible within a 1.30 millimeter average error bound. The virtual mandible may be further used as a reference target for registering other anatomical models, such as the lungs, on the HPS. Such registration will be made possible by physical constraints among the mandible and the spinal column in the horizontal normal rest position.

cs.GR↗

arXiv2018

VIEW: A Virtual Interactive Web-based Learning Environment for Engineering

The use of computer-aided and web-based educational technologies such as Virtual Learning Environments (VLE) has increased significantly in the recent past. One example of such a VLE is Virtual Interactive Engineering on the Web (VIEW). VIEW is a 3D virtual, interactive, student centered, framework of web-based modules based on the Extensible 3D standard. These modules are dedicated to the improvement of student success and learning. In this paper, an overview of the recent developments in VIEW along with associated assessment results is presented. An experimental study was also performed to compare the learning experience and performance of students in a physical dissection activity vs. that in a virtual dissection activity using a VIEW module. The results of this study show that students can meet given learning objectives and that there is limited difference in their learning and performance irrespective of a physical or virtual setting.

cs.HC↗

arXiv2018

Haptic Feedback Systems in Medical Education

This paper brings into discussion some of the most relevant technological challenges involving haptic systems in medical education. One of these challenges is choosing the suitable haptic hardware, API or framework for developing a visuo-haptic e-Learning system. The decision is based on several criteria such as the multimodal resources needed by the software system, compatibility with haptic devices and the dynamic configuration of the scene. Another challenge is related to the software system reactivity in conjunction with the user's actions. The immediate haptic feedback from the virtual models, together with the synchronization of the rendered haptic and visual cues seen by the users are essential for enhancing the user's learning ability. Visuo-haptic simulation facilitates accurate training scenarios of medical protocols and surgical processes.

cs.HC↗

arXiv2018

Design and Assessment for Hybrid Courses: Insights and Overviews

Technology is influencing education, providing new delivery and assessment models. A combination between online and traditional course, the hybrid (blended) course, may present a solution with many benefits as it provides a gradual transition towards technology enabled education. This research work provides a set of definitions for several course delivery approaches, and evaluates five years of data from a course that has been converted from traditional face-to-face delivery, to hybrid delivery. The collected experimental data proves that the revised course, in the hybrid delivery mode, is at least as good, if not better, than it previously was and it provides some benefits in terms of student retention.

cs.HC↗