Sergio Casas | Universitat de València (original) (raw)

Papers by Sergio Casas

The geometric calibration of projectors is a demanding task, particularly for the industry of vir... more 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 approaches, and has been designed by considering the spatial restrictions of virtual reality simulators. The method has been validated from a mathematical point of view, and the complete system—which is currently installed in a shopping mall in Spain—has been tested by different users.

Motion platforms and motion cueing algorithms (MCA) have been included in virtual reality applica... more Motion platforms and motion cueing algorithms (MCA) have been included in virtual reality applications for several decades. They are necessary to provide suitable inertial cues in vehicle simulators. However, the great number of operational constraints that these devices and algorithms suffer, namely limited physical space, elevated costs, absence of sufficient power, difficulty of tuning and lack of standardized assessment methods, have hindered their widespread use. This work tries to clarify open questions in the field, such as: How important is MCA tuning? How much does size, number of DOF and power/latency matter? Can the absence of motion be better than poor motion cueing? What are the key factors that should be addressed to enhance the design of these devices? Although absolute certain answers cannot be given, this paper tries to clarify these research questions by performing massive experiments with simulated motion platforms of different types, sizes and powers. The informa...

Home automation (HA) systems can be considered as an implementation of the internet of everything... more 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 solutions, and IP-based HA systems. This chapter proposes a way to deal with the interoperability problem by means of the open-source platform openHAB. It is based on the concept of a home automation bus, an idea that enables the separation of the physical and the functional view of any device, allowing ...

Applied Sciences

Due to the increasing use of data analytics, information visualization is getting more and more i... more Due to the increasing use of data analytics, information visualization is getting more and more important. However, as data get more complex, so does visualization, often leading to ad hoc and cumbersome solutions. A recent alternative is the use of the so-called knowledge-assisted visualization tools. In this paper, we present STMaps (Spatio-Temporal Maps), a multipurpose knowledge-assisted ontology-based visualization tool of spatio-temporal data. STMaps has been (originally) designed to show, by means of an interactive map, the content of the SILKNOW project, a European research project on silk heritage. It is entirely based on ontology support, as it gets the source data from an ontology and uses also another ontology to define how data should be visualized. STMaps provides some unique features. First, it is a multi-platform application. It can work embedded in an HTML page and can also work as a standalone application over several computer architectures. Second, it can be used ...

2018 IEEE International Symposium on Mixed and Augmented Reality Adjunct (ISMAR-Adjunct)

Figure 1: The proposed occlusion system. A real object (left) is augmented (right) with virtual c... more Figure 1: The proposed occlusion system. A real object (left) is augmented (right) with virtual content through the use of an inverse hole-based depth mask, shown with green color, instead of the traditional one, depicted in red color (middle).

Smart Systems Design, Applications, and Challenges

In this chapter, authors deal with the problem of visualizing summarized information in a complex... more 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 management of the city. The SAR system relies on a multi-projector mapping procedure, and therefore authors also explain the technical details that the calibration and implementation of this type of AR application requires.

Smart Systems Design, Applications, and Challenges

Multisensory stimuli can be integrated in systems that make use of different paradigms, such as V... more 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 supports and integrates various types of displays and interactive applications, providing users with multisensory experiences.

Research Anthology on Usage and Development of Open Source Software

Home automation (HA) systems can be considered as an implementation of the internet of everything... more 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 solutions, and IP-based HA systems. This chapter proposes a way to deal with the interoperability problem by means of the open-source platform openHAB. It is based on the concept of a home automation bus, an idea that enables the separation of the physical and the functional view of any device, allowing ...

Recent Advances in 3D Imaging, Modeling, and Reconstruction

Cultural heritage (CH) tells us about our roots, and therefore, constitutes a rich value for the ... more 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 authors focus their attention in the technologies of virtual reality (VR), augmented reality (AR), and serious games (SGs). They aim to explore these technologies in order to show their benefits in the dissemination and understanding of CH. Though the work involving them is not trivial, and usuall...

Research Anthology on Rehabilitation Practices and Therapy

Virtual and Augmented Reality are technologies widely used in a variety of areas, including the m... more 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 these enhanced mirrors could bring for the mental health treatment.

Applied Sciences

The incorporation of the elderly into digital leisure has been especially driven by the developme... more The incorporation of the elderly into digital leisure has been especially driven by the development of games and applications that link the experience of play with beneficial effects for the user. Some of these benefits arise at a cognitive level, fostering intellectual activity of adults through playful experiences that combine audio-visual entertainment with brain training. Seniors are also engaged by active video games that use control interfaces to perform physical actions or activities, encouraging motor play. In this paper, we present the application of HybridPLAY for the elderly, a self-developed technology initially thought to transform playgrounds into scenarios for a set of interactive digital games. In this paper, we show that, although HybridPLAY was initially developed for children and teenagers, the versatile features of this technology make it appropriate also for the elderly. After having tested HybridPLAY with a small group of seniors who completed a usability test ...

DYNA INGENIERIA E INDUSTRIA

Libro de Actas IN-RED 2017 - III Congreso Nacional de Innovación Educativa y de Docencia en Red, Jul 13, 2017

Both the degree in Telematic Engineering and the degree in Multimedia Engineering have a subject ... more Both the degree in Telematic Engineering and the degree in Multimedia Engineering have a subject of Software Engineering. One competence of this subject is to train students as professionals for the real world. For this aim, we have applied two versions of a role-playing game where there are both clients, who ask for a system development project, and developers. In the degree in Telematic Ingineering, the teacher plays the role of client, while students play the role of developers. Regarding the degree of Multimedia Engineering, students play both the role of client and developer at the same time (for different projects). In this paper, we tackle both experiences and we show a comparative of results. For Telematic Engineering, we ensure that the workload is the same for all the students. Moreover, the teacher can control directly the work of the students since he/she knows perfectly the project that needs to be developed. Regarding Multimedia Engineering, we try to enhance the students' creativity since they must devise themselves a project to develop. Moreover, the students learn how to develop both roles, which can be useful for the real world.

2018 IEEE International Symposium on Mixed and Augmented Reality Adjunct (ISMAR-Adjunct), Oct 1, 2018

Figure 1: The proposed occlusion system. A real object (left) is augmented (right) with virtual c... more Figure 1: The proposed occlusion system. A real object (left) is augmented (right) with virtual content through the use of an inverse hole-based depth mask, shown with green color, instead of the traditional one, depicted in red color (middle).

Multimedia Tools and Applications

The inspection of prefabricated buildings involves different stages and tasks such as the collect... more The inspection of prefabricated buildings involves different stages and tasks such as the collection of measurements, the visual inspection of components and the written annotation of defects. Traditionally, inspectors have documented the process, the kind of defects and the proposed correction measures in paper format, hindering the collaboration with other experts (either simultaneously or asynchronously) and the collection of other types of annotations (e.g. images, 3D elements). In this paper, we present an AR tool designed to aid inspectors during this process. The tool has many benefits, as it allows simultaneously performing a collaborative inspection, taking multitype and geolocated annotations, their monitoring and edition, and performing in situ augmented visualizations. The quantitative and qualitative user evaluation carried out with our tool in a real environment (including usability and satisfaction evaluations) shows the relevance that such a technology might bring to the field and prove that our tool is usable and fulfils most of the inspectors’ expectations.

Virtual Reality

Motion platforms and motion cueing algorithms (MCA) have been included in virtual reality applica... more Motion platforms and motion cueing algorithms (MCA) have been included in virtual reality applications for several decades. They are necessary to provide suitable inertial cues in vehicle simulators. However, the great number of operational constraints that these devices and algorithms suffer, namely limited physical space, elevated costs, absence of sufficient power, difficulty of tuning and lack of standardized assessment methods, have hindered their widespread use. This work tries to clarify open questions in the field, such as: How important is MCA tuning? How much does size, number of DOF and power/latency matter? Can the absence of motion be better than poor motion cueing? What are the key factors that should be addressed to enhance the design of these devices? Although absolute certain answers cannot be given, this paper tries to clarify these research questions by performing massive experiments with simulated motion platforms of different types, sizes and powers. The information obtained from these experiments will be important to customize the design of real devices for this particular use. Ideally, subjective experiments with human experts would have been preferred. However, the use of simulated devices allows comparing many different motion platforms. In this paper, forty of these devices are simulated, optimized by means of a heuristic algorithm and compared with objective indicators in order to measure their relative performance using the classical MCA, something that would require an unreasonable amount of effort with real users and real devices. The obtained results show that MCA tuning is of the utmost importance in motion cueing. They also suggest that high power can usually compensate for lack of size and that a 6-DOF motion platform slightly improves the performance of a 3-DOF motion platform.

Revista Iberoamericana de Automática e Informática Industrial RIAI

Resumen El uso de plataformas robóticas de movimiento en simuladores de vehículos y aplicaciones ... more Resumen 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 simulador se construye con el objetivo de permitir la simulación rápida de manipuladores robóticos y se ejemplifica con una plataforma de dos grados de libertad, aunque el método propuesto podría emplearse en otros dispositivos. En las pruebas realizadas se valida la precisión y velocidad de la simulación, concluyéndose que se obtiene una fidelidad satisfactoria y una velocidad de simulación elevada que permite emplear el simulador como sustituto del hardware real con algoritmos de washout.

Multimodal Technologies and Interaction

The use of augmented reality (AR) in cultural heritage (CH) applications opens a whole set of pos... more The use of augmented reality (AR) in cultural heritage (CH) applications opens a whole set of possibilities, including the virtual transformation of CH elements. This paper presents TinajAR, a mirror-based AR application designed to serve both as an edutainment application in the field of CH and also as an artistic expression. As an edutainment application, TinajAR features a multi-marker video-based AR application designed to show virtual ceramic pieces and explain the pottery process through virtual avatars. As an artistic expression, TinajAR seeks to reinterpret an ancient type of cellar called calado, which was used in the past for storing wine in northern Spain. The reinterpretation consists in giving a different but meaningful use to the space. TinajAR was used by around 1800 people during a ceramics exhibition in La Rioja, Spain and was assessed at the satisfaction level with 56 users by means of a system usability scale, giving very satisfactory results.

The geometric calibration of projectors is a demanding task, particularly for the industry of vir... more 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 approaches, and has been designed by considering the spatial restrictions of virtual reality simulators. The method has been validated from a mathematical point of view, and the complete system—which is currently installed in a shopping mall in Spain—has been tested by different users.

Motion platforms and motion cueing algorithms (MCA) have been included in virtual reality applica... more Motion platforms and motion cueing algorithms (MCA) have been included in virtual reality applications for several decades. They are necessary to provide suitable inertial cues in vehicle simulators. However, the great number of operational constraints that these devices and algorithms suffer, namely limited physical space, elevated costs, absence of sufficient power, difficulty of tuning and lack of standardized assessment methods, have hindered their widespread use. This work tries to clarify open questions in the field, such as: How important is MCA tuning? How much does size, number of DOF and power/latency matter? Can the absence of motion be better than poor motion cueing? What are the key factors that should be addressed to enhance the design of these devices? Although absolute certain answers cannot be given, this paper tries to clarify these research questions by performing massive experiments with simulated motion platforms of different types, sizes and powers. The informa...

Home automation (HA) systems can be considered as an implementation of the internet of everything... more 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 solutions, and IP-based HA systems. This chapter proposes a way to deal with the interoperability problem by means of the open-source platform openHAB. It is based on the concept of a home automation bus, an idea that enables the separation of the physical and the functional view of any device, allowing ...

Applied Sciences

Due to the increasing use of data analytics, information visualization is getting more and more i... more Due to the increasing use of data analytics, information visualization is getting more and more important. However, as data get more complex, so does visualization, often leading to ad hoc and cumbersome solutions. A recent alternative is the use of the so-called knowledge-assisted visualization tools. In this paper, we present STMaps (Spatio-Temporal Maps), a multipurpose knowledge-assisted ontology-based visualization tool of spatio-temporal data. STMaps has been (originally) designed to show, by means of an interactive map, the content of the SILKNOW project, a European research project on silk heritage. It is entirely based on ontology support, as it gets the source data from an ontology and uses also another ontology to define how data should be visualized. STMaps provides some unique features. First, it is a multi-platform application. It can work embedded in an HTML page and can also work as a standalone application over several computer architectures. Second, it can be used ...

2018 IEEE International Symposium on Mixed and Augmented Reality Adjunct (ISMAR-Adjunct)

Figure 1: The proposed occlusion system. A real object (left) is augmented (right) with virtual c... more Figure 1: The proposed occlusion system. A real object (left) is augmented (right) with virtual content through the use of an inverse hole-based depth mask, shown with green color, instead of the traditional one, depicted in red color (middle).

Smart Systems Design, Applications, and Challenges

In this chapter, authors deal with the problem of visualizing summarized information in a complex... more 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 management of the city. The SAR system relies on a multi-projector mapping procedure, and therefore authors also explain the technical details that the calibration and implementation of this type of AR application requires.

Smart Systems Design, Applications, and Challenges

Multisensory stimuli can be integrated in systems that make use of different paradigms, such as V... more 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 supports and integrates various types of displays and interactive applications, providing users with multisensory experiences.

Research Anthology on Usage and Development of Open Source Software

Home automation (HA) systems can be considered as an implementation of the internet of everything... more 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 solutions, and IP-based HA systems. This chapter proposes a way to deal with the interoperability problem by means of the open-source platform openHAB. It is based on the concept of a home automation bus, an idea that enables the separation of the physical and the functional view of any device, allowing ...

Recent Advances in 3D Imaging, Modeling, and Reconstruction

Cultural heritage (CH) tells us about our roots, and therefore, constitutes a rich value for the ... more 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 authors focus their attention in the technologies of virtual reality (VR), augmented reality (AR), and serious games (SGs). They aim to explore these technologies in order to show their benefits in the dissemination and understanding of CH. Though the work involving them is not trivial, and usuall...

Research Anthology on Rehabilitation Practices and Therapy

Virtual and Augmented Reality are technologies widely used in a variety of areas, including the m... more 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 these enhanced mirrors could bring for the mental health treatment.

Applied Sciences

The incorporation of the elderly into digital leisure has been especially driven by the developme... more The incorporation of the elderly into digital leisure has been especially driven by the development of games and applications that link the experience of play with beneficial effects for the user. Some of these benefits arise at a cognitive level, fostering intellectual activity of adults through playful experiences that combine audio-visual entertainment with brain training. Seniors are also engaged by active video games that use control interfaces to perform physical actions or activities, encouraging motor play. In this paper, we present the application of HybridPLAY for the elderly, a self-developed technology initially thought to transform playgrounds into scenarios for a set of interactive digital games. In this paper, we show that, although HybridPLAY was initially developed for children and teenagers, the versatile features of this technology make it appropriate also for the elderly. After having tested HybridPLAY with a small group of seniors who completed a usability test ...

DYNA INGENIERIA E INDUSTRIA

Libro de Actas IN-RED 2017 - III Congreso Nacional de Innovación Educativa y de Docencia en Red, Jul 13, 2017

Both the degree in Telematic Engineering and the degree in Multimedia Engineering have a subject ... more Both the degree in Telematic Engineering and the degree in Multimedia Engineering have a subject of Software Engineering. One competence of this subject is to train students as professionals for the real world. For this aim, we have applied two versions of a role-playing game where there are both clients, who ask for a system development project, and developers. In the degree in Telematic Ingineering, the teacher plays the role of client, while students play the role of developers. Regarding the degree of Multimedia Engineering, students play both the role of client and developer at the same time (for different projects). In this paper, we tackle both experiences and we show a comparative of results. For Telematic Engineering, we ensure that the workload is the same for all the students. Moreover, the teacher can control directly the work of the students since he/she knows perfectly the project that needs to be developed. Regarding Multimedia Engineering, we try to enhance the students' creativity since they must devise themselves a project to develop. Moreover, the students learn how to develop both roles, which can be useful for the real world.

2018 IEEE International Symposium on Mixed and Augmented Reality Adjunct (ISMAR-Adjunct), Oct 1, 2018

Figure 1: The proposed occlusion system. A real object (left) is augmented (right) with virtual c... more Figure 1: The proposed occlusion system. A real object (left) is augmented (right) with virtual content through the use of an inverse hole-based depth mask, shown with green color, instead of the traditional one, depicted in red color (middle).

Multimedia Tools and Applications

The inspection of prefabricated buildings involves different stages and tasks such as the collect... more The inspection of prefabricated buildings involves different stages and tasks such as the collection of measurements, the visual inspection of components and the written annotation of defects. Traditionally, inspectors have documented the process, the kind of defects and the proposed correction measures in paper format, hindering the collaboration with other experts (either simultaneously or asynchronously) and the collection of other types of annotations (e.g. images, 3D elements). In this paper, we present an AR tool designed to aid inspectors during this process. The tool has many benefits, as it allows simultaneously performing a collaborative inspection, taking multitype and geolocated annotations, their monitoring and edition, and performing in situ augmented visualizations. The quantitative and qualitative user evaluation carried out with our tool in a real environment (including usability and satisfaction evaluations) shows the relevance that such a technology might bring to the field and prove that our tool is usable and fulfils most of the inspectors’ expectations.

Virtual Reality

Motion platforms and motion cueing algorithms (MCA) have been included in virtual reality applica... more Motion platforms and motion cueing algorithms (MCA) have been included in virtual reality applications for several decades. They are necessary to provide suitable inertial cues in vehicle simulators. However, the great number of operational constraints that these devices and algorithms suffer, namely limited physical space, elevated costs, absence of sufficient power, difficulty of tuning and lack of standardized assessment methods, have hindered their widespread use. This work tries to clarify open questions in the field, such as: How important is MCA tuning? How much does size, number of DOF and power/latency matter? Can the absence of motion be better than poor motion cueing? What are the key factors that should be addressed to enhance the design of these devices? Although absolute certain answers cannot be given, this paper tries to clarify these research questions by performing massive experiments with simulated motion platforms of different types, sizes and powers. The information obtained from these experiments will be important to customize the design of real devices for this particular use. Ideally, subjective experiments with human experts would have been preferred. However, the use of simulated devices allows comparing many different motion platforms. In this paper, forty of these devices are simulated, optimized by means of a heuristic algorithm and compared with objective indicators in order to measure their relative performance using the classical MCA, something that would require an unreasonable amount of effort with real users and real devices. The obtained results show that MCA tuning is of the utmost importance in motion cueing. They also suggest that high power can usually compensate for lack of size and that a 6-DOF motion platform slightly improves the performance of a 3-DOF motion platform.

Revista Iberoamericana de Automática e Informática Industrial RIAI

Resumen El uso de plataformas robóticas de movimiento en simuladores de vehículos y aplicaciones ... more Resumen 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 simulador se construye con el objetivo de permitir la simulación rápida de manipuladores robóticos y se ejemplifica con una plataforma de dos grados de libertad, aunque el método propuesto podría emplearse en otros dispositivos. En las pruebas realizadas se valida la precisión y velocidad de la simulación, concluyéndose que se obtiene una fidelidad satisfactoria y una velocidad de simulación elevada que permite emplear el simulador como sustituto del hardware real con algoritmos de washout.

Multimodal Technologies and Interaction

The use of augmented reality (AR) in cultural heritage (CH) applications opens a whole set of pos... more The use of augmented reality (AR) in cultural heritage (CH) applications opens a whole set of possibilities, including the virtual transformation of CH elements. This paper presents TinajAR, a mirror-based AR application designed to serve both as an edutainment application in the field of CH and also as an artistic expression. As an edutainment application, TinajAR features a multi-marker video-based AR application designed to show virtual ceramic pieces and explain the pottery process through virtual avatars. As an artistic expression, TinajAR seeks to reinterpret an ancient type of cellar called calado, which was used in the past for storing wine in northern Spain. The reinterpretation consists in giving a different but meaningful use to the space. TinajAR was used by around 1800 people during a ceramics exhibition in La Rioja, Spain and was assessed at the satisfaction level with 56 users by means of a system usability scale, giving very satisfactory results.