0000000000040948
AUTHOR
Sergio Casas
showing 36 related works from this author
A VR-Enhanced Rollover Car Simulator and Edutainment Application for Increasing Seat Belt Use Awareness
2021
Most countries have active road safety policies that seek the objective of reducing deaths in traffic accidents. One of the main factors in this regard is the awareness of the safety measures, one of the most important being the correct usage of the seat belt, a device that is known to save thousands of lives every year. The presented work shows a VR-enhanced edutainment application designed to increase awareness on the use of seat belts. For this goal, a motorized rollover system was developed that, synchronized with a VR application (shown in a head-mounted display for each user inside a real car), rolls over this car with up to four passengers inside. This way, users feel the sensations …
An empirical evaluation of two natural hand interaction systems in augmented reality
2022
AbstractHuman-computer interaction based on hand gesture tracking is not uncommon in Augmented Reality. In fact, the most recent optical Augmented Reality devices include this type of natural interaction. However, due to hardware and system limitations, these devices, more often than not, settle for semi-natural interaction techniques, which may not always be appropriate for some of the tasks needed in Augmented Reality applications. For this reason, we compare two different optical Augmented Reality setups equipped with hand tracking. The first one is based on a Microsoft HoloLens (released in 2016) and the other one is based on a Magic Leap One (released more than two years later). Both d…
Towards an extensible simulator of real motion platforms
2014
Abstract The limitations of a real motion platform will not normally be discovered until it is completely built and tested. Late identification of its limitations imposes the necessity of a redesign of the motion platform. This, in turn, incurs important and significant economic costs for the manufacturer. Note that any change in the original design of the motion platform requires an investment in resources, money and time in order to perform the re-design of the platform. The main contribution of this paper is to address this problem by creating a virtual motion platform (VMP). This virtual motion platform is a computer-based simulation of a real motion platform which produces the same out…
Lessons Learned from the Design and Development of Vehicle Simulators
2018
Vehicle simulators are crucial tools used in a variety of areas, such as aviation, driving, or maritime transportation. International standards require the use of motion-based vehicle simulators in training scenarios. However, the huge variety of applications and requirements makes it difficult for end users to find a motion-based commercial solution that fulfils their needs. On the other hand, commercial solutions are usually expensive as they involve specific hardware and software. Although some ad-hoc solutions have been reported, a generalized design strategy is needed. In this article, the authors emphasize the need for finding a development methodology for these important tools and th…
An Augmented Reality (AR) CAD System at Construction Sites
2011
Augmented Reality (AR) technologies allow computer-generated content to be superimposed over a live camera view of the real world. Although AR is still a very promising technology, currently only a few commercial applications for industrial purposes exploit the potential of adding contextual content to real scenarios. Most of AR applications are oriented to fields such as education or entertainment, where the requirements in terms of repeatability, fault tolerance, reliability and safety are low. Different visualization devices, tracking methods and interaction techniques are described in the literature, establishing a classification between Indoor and Outdoor AR systems. On the one hand, t…
To Move or Not to Move?
2019
This chapter deals with the problem of including motion cues in VR applications. From the challenges of this technology to the latest trends in the field, the authors discuss the benefits and problems of including these particular perceptual cues. First, readers will know how motion cues are usually generated in simulators and VR applications in general. Then, the authors list the major problems of this process and the reasons why its development has not followed the pace of the rest of VR elements (mainly the display technology), reviewing the motion vs. no-motion question from several perspectives. The general answer to this discussion is that motion cues are necessary in VR applications—…
Interacting with Augmented Reality Mirrors
2018
This chapter deals with the topic of Augmented Reality Mirrors (ARMs) – a kind of specular interfaces making use of Augmented Reality technology. The review presented in the chapter first analyses the current setups for the construction of ARMs. Secondly, it presents a study on their potential for inferring in human perception (e.g. behaviour and emotions) and the high interactivity potential and usability they have. In the third place, it shows their use in different areas of knowledge, namely entertainment, edutainment, clothing, arts and medical therapy. Then, the chapter presents a discussion, highlighting the current technological barriers and the need for more research. Finally, futur…
Multisensory Experiences in Virtual Reality and Augmented Reality Interaction Paradigms
2020
Multisensory stimuli can be integrated in systems that make use of different paradigms, such as Virtual Reality (VR), Augmented Reality (AR) or, in a wider sense, Mixed Reality (MR), enhancing user experiences within the virtual content. However, despite the many technological solutions that exist (both hardware and software), only visual and sonic stimuli can be considered as highly integrated in consumer-grade applications. This chapter addresses the current state of the art in multisensory experiences, taking also in consideration the aforementioned interaction paradigms, and brings the benefits and challenges. As an example, authors introduce ROMOT, a RObotic 3D-MOvie Theatre, that supp…
Optimization of 3-DOF Parallel Motion Devices for Low-Cost Vehicle Simulators
2017
Motion generation systems are becoming increasingly important in certain Virtual Reality (VR) applications, such as vehicle simulators. This paper deals with the analysis of the Inverse Kinematics (IK) and the reachable workspace of a three-degrees-of-freedom (3-DOF) parallel manipulator, proposing different transformations and optimizations in order to simplify its use with Motion Cueing Algorithms (MCA) for self-motion generation in VR simulators. The proposed analysis and improvements are performed on a 3-DOF heave-pitch-roll manipulator with rotational motors, commonly used for low-cost motion-based commercial simulators. The analysis has been empirically validated against a real 3-DOF …
A comparative analysis of two immersive virtual reality systems in the integration and visualization of natural hand interaction
2022
AbstractIt is generally accepted that the use of natural interaction provides a positive impact in Virtual Reality (VR) applications. Therefore, it is important to understand what is the best way to integrate and visualize this feature in VR. For this reason, this paper presents a comparative study of the integration of natural hand interaction in two immersive VR systems: a Cave Audio Visual Experience (CAVE) system –where users’ real hands are visible– and a non-see-through Head-Mounted Display (HMD) system –where only a virtual representation of the hands is possible–. In order to test the suitability of using this type of interaction in a CAVE and compare it to an HMD, we raise six rese…
From the Paper to the Tablet: On the Design of an AR-Based Tool for the Inspection of Pre-Fab Buildings. Preliminary Results of the SIRAE Project
2018
Energy-efficient Buildings (EeB) are demanded in today’s constructions, fulfilling the requirements for green cities. Pre-fab buildings, which are modularly fully-built in factories, are a good example of this. Although this kind of building is quite new, the in situ inspection is documented using traditional tools, mainly based on paper annotations. Thus, the inspection process is not taking advantage of new technologies. In this paper, we present the preliminary results of the SIRAE project that aims to provide an Augmented Reality (AR) tool that can seamlessly aid in the regular processes of pre-fab building inspections to detect and eliminate the possible existing quality and ener…
Applying particle swarm optimization to the motion-cueing-algorithm tuning problem
2017
The MCA tuning problem consists in finding the best values for the parameters/coefficients of Motion Cueing Algorithms (MCA). MCA are used to control the movements of robotic motion platforms employed to generate inertial cues in vehicle simulators. This problem is traditionally approached with a manual pilot-in-the-loop subjective tuning, based on the opinion of several pilots/drivers. Instead, this paper proposes applying Particle Swarm Optimization (PSO) to solve this problem, using simulated motion platforms and objective indicators rather than subjective opinions. Results show that PSO-based tuning can provide a suitable solution for this complex optimization problem.
Development of a Hybrid Method to Generate Gravito-Inertial Cues for Motion Platforms in Highly Immersive Environments
2021
Motion platforms have been widely used in Virtual Reality (VR) systems for decades to simulate motion in virtual environments, and they have several applications in emerging fields such as driving assistance systems, vehicle automation and road risk management. Currently, the development of new VR immersive systems faces unique challenges to respond to the user’s requirements, such as introducing high-resolution 360° panoramic images and videos. With this type of visual information, it is much more complicated to apply the traditional methods of generating motion cues, since it is generally not possible to calculate the necessary corresponding motion properties that are needed to …
Current Trends on the Acquisition, Virtual Representation, and Interaction of Cultural Heritage
2020
Cultural heritage (CH) tells us about our roots, and therefore, constitutes a rich value for the society. Its conservation, dissemination, and understanding are of utmost importance. In order to preserve CH for the upcoming generations, it needs to be documented, a process that nowadays is done digitally. Current trends involve a set of technologies (cameras, scanners, etc.) for the shape and radiometric acquisition of assets. Also, intangible CH can be digitally documented in a variety of forms. Having such assets virtualized, a proper dissemination channel is of relevance, and recently, new technologies that make use of interaction paradigms have emerged. Among them, in this chapter, the …
Heuristics for solving the parameter tuning problem in motion cueing algorithms.
2017
[ES] Diversos tipos de plataformas robóticas son empleadas habitualmente para la generación de claves gravito-inerciales en simuladores. Además del control de los actuadores, dichas plataformas deben ejecutar complejos algoritmos de control conocidos como algoritmos de washout, que deben ser ajustados para que el movimiento generado sea similar al simulado. El ajuste de dichos algoritmos es complejo por el elevado número de parámetros que poseen. Además, dicho ajuste se ha venido realizando tradicionalmente de modo manual mediante evaluaciones subjetivas. En este trabajo, los autores proponen un método automático de ajuste basado en optimización heurística, métricas objetivas, y simulación …
A Hybrid Virtual-Augmented Serious Game to Improve Driving Safety Awareness
2018
The use of 3D virtual content and Augmented Reality (AR) in certain applications allows designing tools and serious games that are more attractive to the potential users. Focusing on the area of learning and education, these technologies can be adapted to the requirements of the application that needs to be developed, to the available devices on which they are expected to run and also to the learning content. However, in most applications only a single interaction paradigm and a single visualization mode is used, restricting the potential benefits of the system. In this paper, we propose a software application designed to improve driving safety awareness and learning for both adults and chi…
Towards a simulation-based tuning of motion cueing algorithms
2016
Abstract This paper deals with the problem of finding the best values for the parameters of Motion Cueing Algorithms (MCA). MCA are responsible for controlling the movements of robotic motion platforms used to generate the gravito-inertial cues of vehicle simulators. The values of their multiple parameters, or coefficients, are hard to establish and they dramatically change the behaviour of MCA. The problem has been traditionally addressed in a subjective, partially non-systematic, iterative, time-consuming way, by seeking pilot/driver feedback on the generated motion cues. The aim of this paper is to introduce a different approach to solve the problem of MCA tuning, by making use of a simu…
A particle swarm approach for tuning washout algorithms in vehicle simulators
2018
Abstract The MCA tuning problem involves finding the most appropriate values for the parameters (or coefficients) of Motion Cueing Algorithms (MCA), also known as washout algorithms. These algorithms are designed to control the movements of the robotic mechanisms, referred to as motion platforms, employed to generate inertial cues in vehicle simulators. This problem can be approached in several different ways. The traditional approach is to perform a manual pilot-in-the-loop subjective tuning, using the opinion of several pilots/drivers to guide the process. A more systematic approach is to use optimization techniques to explore the vast parameter space of the MCA, using objective motion fi…
Virtual and Augmented Reality Mirrors for Mental Health Treatment
2020
Virtual and Augmented Reality are technologies widely used in a variety of areas, including the medical sector. On the other hand, regular mirrors have been traditionally used as tools to aid in mental health treatment for a variety of diseases and disorders. Although it is possible to build Virtual and Augmented Reality experiences based on mirror metaphors, there are very few contributions of this kind in the medical sector. In this chapter, the great benefits that regular mirrors have brought for mental health treatment are addressed. In addition, a review on the state of the art in mirror-based Virtual and Augmented Reality applications is given, highlighting the potential benefits that…
A Multi-Projector Calibration Method for Virtual Reality Simulators with Analytically Defined Screens
2017
The geometric calibration of projectors is a demanding task, particularly for the industry of virtual reality simulators. Different methods have been developed during the last decades to retrieve the intrinsic and extrinsic parameters of projectors, most of them being based on planar homographies and some requiring an extended calibration process. The aim of our research work is to design a fast and user-friendly method to provide multi-projector calibration on analytically defined screens, where a sample is shown for a virtual reality Formula 1 simulator that has a cylindrical screen. The proposed method results from the combination of surveying, photogrammetry and image processing approac…
ROMOT: A Robotic 3D-Movie Theater Allowing Interaction and Multimodal Experiences
2017
In this paper we introduce ROMOT, a RObotic 3D-MOvie Theater. ROMOT is built with a robotic motion platform, includes multimodal devices and supports audience-film interaction. Differently from other similar systems, ROMOT is highly versatile as it can support different setups, integrated hardware and contents. Regarding to the setups, here we present a first-person movie, a mixed reality environment, a virtual reality interactive environment and an augmented reality mirror-based scene. Regarding to integrated hardware, the system currently integrates a variety of devices and displays that allow audiences to see, hear, smell, touch and feel the movement, all synchronized with the filmic exp…
A Case Study on Vestibular Sensations in Driving Simulators.
2022
Motion platforms have been used in simulators of all types for several decades. Since it is impossible to reproduce the accelerations of a vehicle without limitations through a physically limited system (platform), it is common to use washout filters and motion cueing algorithms (MCA) to select which accelerations are reproduced and which are not. Despite the time that has passed since their development, most of these algorithms still use the classical washout algorithm. In the use of these MCAs, there is always information that is lost and, if that information is important for the purpose of the simulator (the training simulators), the result obtained by the users of that simulator will no…
Motion-Cuing Algorithms
2015
Objective:The aim of this study was to characterize the human response to motion-cuing algorithms (MCAs) by comparing users’ perception to several proposed objective indicators.Background:Other researchers have proposed several MCAs, but few improvements have been achieved lately. One of the reasons for this lack of progress is that fair comparisons between different algorithms are hard to achieve, for their evaluation needs to be performed with humans and the tuning process is slow.Method:This characterization is performed by means of a comparison of the subjective perception of vehicle simulation users (90 participants) against several proposed objective indicators that try to measure MCA…
Simulation of parallel mechanisms for motion cueing generation in vehicle simulators using AM-FM bi-modulated signals
2018
Abstract The use of robotic motion platforms in vehicle simulators is relatively common. However, the process of testing and tuning the so-called washout algorithms, used for motion cueing generation in motion-based vehicle simulators, is complex. This process can be reduced in cost, simplified, improved, shortened and performed safer if virtual motion platforms are used instead of real devices. This paper deals with identifying a method to perform a fast but reliable simulation of parallel mechanisms to be used for motion cueing generation. The method relies on the use of Laplacian polynomial transfer function models by means of using AM-FM bi-modulated signals as reference inputs to achie…
Motion Cueing Algorithms: A Review
2017
Robotic motion platforms are commonly used in motion-based vehicle simulation. However, the reproduction of realistic accelerations within a reduced workspace is a major challenge. Thus, high-level control strategies commonly referred to as motion cueing algorithms (MCA) are required to convert the simulated vehicle physical state into actual motion for the motion platform. This paper reviews the most important strategies for the generation of motion cues in simulators, listing the advantages and drawbacks of the different solutions. The motion cueing problem, a general scheme and the four most common approaches – classical washout, adaptive washout, optimal control and model predictive con…
Simulación de Plataformas Robóticas de Movimiento para Aplicaciones de Realidad Virtual Mediante Filtros Digitales
2017
[ES] El uso de plataformas robóticas de movimiento en simuladores de vehículos y aplicaciones de Realidad Virtual es relativamente habitual. Sin embargo, el ajuste de los algoritmos que controlan su funcionamiento, denominados algoritmos de washout, no es sencillo y requiere de numerosas pruebas hasta obtener una apropiada fidelidad de movimiento. Disponer de herramientas que permitan simular plataformas de movimiento puede permitir simplificar esta tarea. Es por ello que este trabajo presenta un método para la caracterización y simulación de manipuladores robóticos mediante filtros digitales de segundo orden, sencillo de implementar y ajustar a partir de una caracterización previa. El simu…
Challenges and Trends in Home Automation
2021
Home automation (HA) systems can be considered as an implementation of the internet of everything (IoE) where many devices are linked by intelligent connections in order to improve the quality of life at home. This chapter is dedicated to analyzing current trends and challenges in HA. Energy management, safer homes, and improved control over the house are some of the benefits of HA. However, privacy, security, social disruption, installation/maintenance issues, economic costs, market fragmentation, and low interoperability represent real problems of these IoE solutions. In this regard, the latest proposals in HA try to answer some of these needs with low-cost DIY solutions, wireless solutio…
Addressing the Occlusion Problem in Augmented Reality Environments with Phantom Hollow Objects
2018
Occlusion handling is essential to provide a seamless integration of virtual and real objects in AR applications. Different approaches have been presented with a variety of technologies, environment conditions and methods. Among these methods, 3D model-based occlusion approaches have been extensively used. However, these solutions could be too time-consuming in certain situations, since they must render all the occlusion objects even though they are invisible. For this reason, we propose an inverse 3D model-based solution for handling occlusions, designed for those AR applications in which virtual objects are placed inside a real object with holes or windows. With this restriction, the occl…
MIME: A Mixed-Space Collaborative System with Three Immersion Levels and Multiple Users
2018
Shared spaces for remote collaboration are nowadays possible by considering a variety of users, devices, immersion systems, interaction capabilities, navigation paradigms, etc. There is a substantial amount of research done in this line, proposing different solutions. However, still a more general solution that considers the heterogeneity of the involved actors/items is lacking. In this paper, we present MIME, a mixed-space tri-collaborative system. Differently from other mixed-space systems, MIME considers three different types of users (in different locations) according to the level of immersion in the system, who can interact simultaneously – what we call a tri-collaboration. For the thr…
Augmented Reality-Based Training Systems for Teaching Health and Safety Procedures in Construction
2019
Traditional teaching methods are not always efficient, especially in areas where the concepts to teach relate to physical work that must be done outside the classroom. This is the case of the construction sector, where the teaching of safety procedures is crucial to reduce the number of accidents, but traditional methods fail to highlight the importance of these procedures. The use of computer simulation through new technologies such as augmented reality (AR) can engage more students in order to better understand the concepts. In addition, they can visualize virtual elements superimposed on the real world to simulate the real situations they will later face in construction. This chapter dea…
On the Development of VR and AR Learning Contents for Children on the Autism Spectrum
2018
Autism spectrum disorder (ASD) is an umbrella term used to group a range of brain development disorders. The learning profile of most people with ASD is mainly visual, and VR and AR technologies offer important advantages to provide a visually based mean for gaining access to educational contents. The prices of VR and AR glasses and helmets have fallen. Also, a number of tools that facilitate the development and publication of AR and VR contents have recently appeared. Therefore, a scenario of opportunity for new developments has appeared in this field. This chapter offers guidelines for developing AR and VR learning contents for people on the autism spectrum and analyses those guidelines f…
Mixing Different Realities in a Single Shared Space
2019
The concept of internet of everything involves an intelligent connection of people, processes, data, and things. In this sense, shared spaces aimed to connect different users that collaborate following a common purpose are of relevance to the field. Many computer-based collaborative environments have been proposed in recent years. However, the design of mixed-platform collaborative spaces, in which different paradigms—such as augmented reality (AR) and virtual reality (VR)—are blended, is still uncommon. This chapter aims to analyze the benefits and features of these systems, reviewing existing related works and proposing a series of features for the design of effective mixed-platform colla…
Entertainment virtual reality system for simulation of spaceflights over the surface of the planet Mars
2006
In recent years Virtual Reality technologies have enabled astronomers to recreate and explore three dimensional structures of the Universe for scientific purposes. Mars, due to its scientific interest,has been the focal point of numerous research projects using these technologies, however, none of these virtual reality tools have been developed specifically for entertainment purposes.The focus of this paper is to present MarsVR, as an entertainment research project that educates people on the topography and orography of the planet Mars from the perspective of popular science. Some projects have been designed MarsVR for entertainment purposes and include the latest advances in 3D real time a…
A Mobile Augmented Reality System for Enhancing Electrical Machine Supervision
2019
Electrical machines are used almost everywhere, and our daily life depends on them. For this reason, it is important to articulate mechanisms to control, supervise, and perform proper maintenance of these machines, especially those used in critical industrial process. The SCADA protocol is one of the technologies that eases the operation and supervision of electrical machines. However, the absence of a spatial connection between the SCADA signals and the machines being supervised suggests the use of augmented reality (AR) to fill this void. This chapter describes SIMARA: A Mobile AR application based on a dual computer-vision system (QR-codes and fiducial markers). SIMARA provides a robust …
Multi-Dimensional Acquisition, Representation, and Interaction of Cultural Heritage Tangible Assets
2018
The acquisition, digital representation and interaction of cultural heritage (CH) assets is of high interest for an accurate documentation of our cultural legacy. Detailed studies demand more information on the assets apart from the mere visual appearance or even shape of objects. In this regards, some research works can be found that combine shape with other kind of data, such as radiometric (e.g., IR, thermal radiation, etc.) or semantic information, leading to multi-Dimensional (mD) virtual objects. In this chapter, we review the state of the art of different techniques to deal with mD acquisition of CH tangible assets. We also discuss some representation (e.g., visual, sonic, etc.) and …
Virtual and Augmented Reality for the Visualization of Summarized Information in Smart Cities
2020
In this chapter, authors deal with the problem of visualizing summarized information in a complex system like a smart city. They introduce the topic of smart city in the context of the information revolution that is taking place in the world. Next, they review how this information can be visualized, highlighting immersive 3D methods such as Virtual Reality (VR) and Augmented Reality (AR), which are particularly suitable for these applications, since 2D information does not usually induce a focused and sustained attention. The chapter describes and shows a use case in which VR and Spatial AR (SAR) are used in a smart city system to visualize summarized information about the state and managem…