Virtual and augmented reality

The “Augmented Humans” term refers to the opportunity to improve human possibilities by using innovative technologies such as Artificial Intelligence (AI) and Extended Reality (XR). Digital therapies, particularly suitable for those treatments requiring multiple sessions, are increasingly being adopted for home-based treatment, enabling continuous monitoring and rehabilitation for patients, thus alleviating the burden on healthcare facilities by facilitating remote therapy sessions and follow-up visits. Among these, the Mirror Therapy (MT) for patients suffering from Phantom Limb Pain (PLP) could benefit greatly. This paper proposes a novel “Augmented Humans” framework for the treatment of PLP through home-based MT; the framework is designed to consider the activities carried on by the therapy center, the patient, and the system supporting the treatment. Moreover, an XR-based solution that integrates a Deep Learning (DL) approach has been developed to provide patients with a self-testing and self-assessment tool for conducting at-home rehabilitation sessions independently, even in the absence of physical medical staff. The DL algorithm enables real-time monitoring of rehabilitation exercises and automatic provision of personalized feedback on the gesture's performance, supporting the progressive improvement of the patient's movements and his ability to adhere to the treatment plan. The technical feasibility and usability of the proposed framework have been evaluated with 23 healthy subjects, highlighting an overall positive user experience. Remarkable results were obtained in terms of automatic gesture evaluation, with macro averaged accuracy and F1-score of 95%, paving the way for the adoption of the “Augmented Humans” approach in the healthcare domain.

Keywords: Augmented humans , Augmented therapy , Deep learning , Digital therapy , Extended reality , Home-based treatment , Phantom limb pain

The 2030 Agenda for Sustainable Development, adopted by the United Nations, underscores the importance of inclusive and equitable quality education to promote global awareness. However, progress in this field has been delayed by global crises, including the COVID-19 pandemic and conflicts, highlighting the urgent need for innovative educational solutions. Virtual reality (VR) offers significant potential for creating personalized and inclusive learning environments, particularly in science, technology, engineering, and mathematics (STEM) education. This study presents the development and evaluation of an immersive virtual reality laboratory (VR Lab) focused on material science and mechanics. The VR Lab aims to enhance students' comprehension of complex micro and macro engineering phenomena and strengthen their cognitive skills. Employing a usability and effectiveness evaluation among undergraduate engineering students, the study provides preliminary evidence of VR's efficacy as an educational tool. Results demonstrate notable improvements in students' ability to visualize complex concepts and apply theoretical knowledge to practical scenarios, bridging the gap between theory and practice. The immersive nature of VR not only enhances engagement but also promotes a deeper understanding of key engineering and material science topics. These findings support the integration of VR in STEM education as a complementary tool for enriching learning experiences and promoting educational inclusivity.

Keywords: education , educational technology , engineering , immersive laboratory , virtual reality

Featured Application: Use of virtual reality technology in numerosity estimation tasks. Numeracy, the ability to use basic mathematical skills in everyday life, is essential in modern society. Recent studies have shown a connection between numeracy and visual numerosity perception, yet traditional 2D screen-based assessment methods often lack ecological validity and participant engagement. This study evaluates the viability of conducting numerosity estimation tasks in virtual reality (VR) and to determine whether hallmarks of numerosity processing, typically observed in laboratory settings, can be replicated in immersive environments. Six participants completed a psychophysical evaluation in VR, comparing the numerosity of visual stimuli consisting of two sets of spheres. The VR experiment successfully replicated two distinctive patterns found in traditional psychophysical studies: increased precision and decreased response times at high numerosities. Specifically, Weber fractions drop by approximately a factor of two, with values ranging from ~15% for low and intermediate conditions to ~8% in high numerosities, and response times decreases from ~663 ms for low numerosities to ~593 ms for high numerosities. These findings highlight that VR can be effectively used for numerosity estimation tasks, providing a controlled and immersive environment that traditional methods cannot achieve, while significantly expanding methodological possibilities in psychophysical research.

Keywords: human–computer interaction , numerosity estimation , perception , virtual reality

Underwater Cultural Heritage (UCH) sites offer unique opportunities for archaeological exploration and cultural tourism but remain difficult to interpret due to the environmental constraints of the underwater setting. This paper introduces an integrated Underwater Augmented Reality (UWAR) system designed to support real-Time, site-specific interpretation for recreational divers. The approach combines opto-Acoustic 3D reconstruction with thematic annotation and portable AR delivery. A high-resolution, georeferenced 3D model of the site is generated by fusing multibeam sonar and underwater photogrammetry data. This model provides the spatial framework for distributing interpretive content through georeferenced Points of Interest (POIs), including descriptive texts, images, and 3D reconstructions. The system architecture includes a smart buoy equipped with USBL and GNSS positioning systems and an underwater mobile device for AR visualization. This setup enables real-Time localization and contextual content delivery without the need for permanent infrastructure. The presented UWAR system aims to improve site readability, promote active learning and support sustainable cultural engagement, offering a scalable model for heritage interpretation in underwater environments.

Keywords: Smart Buoy , Underwater 3D Reconstruction , Underwater Augmented Reality (UWAR) , Underwater Cultural Heritage (UCH) , Underwater Navigation

In the context of Industry 4.0, the Operator 4.0 paradigm plays a crucial role in seamlessly integrating new digital technologies into smart factories. These technologies are designed to accommodate workers with varying skills, capabilities, and preferences. To promote the adoption of these innovative digital tools and ensure high user acceptance, it is essential to prioritize human factors and place workers at the heart of the development process. This can be achieved through structured design strategies, such as those employed in user-centered design approaches. Within this framework, this paper introduces an innovative Augmented Reality tool designed to facilitate and streamline real-time inspection activities performed by operators on assembled products at the workplace. The development of this tool was based on a user-centered design approach, which actively engaged end-users at different stages of design and testing phases. User studies were conducted using a real case study to evaluate the usability and user acceptance of the proposed solution. The results are encouraging, indicating a promising path forward for the effective and valid implementation of this AR tool in an industrial setting.

Keywords: Industrial augmented reality , Industry 4.0 , Operator 4.0 , Technology acceptance model , Usability , User-centered design

Performing precise underwater manipulation is a challenging task, especially when applied to the field of underwater cultural heritage (UCH). In fact, errors in measuring the distance between a predefined target and the manipulator's end-effector can lead to significant issues, such as collisions or challenges in grasping objects. Therefore, there is a need to equip operators with tools that enhance their visualization and interaction capabilities, enabling more precise underwater manipulation. To this end, the paper introduces a novel simulation-based approach to increase environmental perception during underwater manipulation operations based on the adoption of stereo vision and acoustic imaging sensors. Specifically, the paper presents the software architecture of an underwater simulator that leverages a graphics engine to replicate a system comprising a Remotely Operated Vehicle (ROV) equipped with a robotic manipulator, stereo camera, and forward-looking sonar. The proposed simulation framework leverages both the Unity engine and ROS2 to enhance underwater robotic simulations. This paper presents preliminary results on stereovision and acoustic simulation, demonstrating how the integration of these sensing modalities improves environmental perception during underwater manipulation tasks.

Keywords: Augmented Reality , Marine Robotics , Robot Operating System 2 (ROS2) , SDG14 , Underwater manipulation

The use of virtual reality (VR) in higher education and training has been widely explored in various fields, with divergent results. This study examines whether VR is a suitable learning support tool compared to traditional methods, such as 2D static slides or physical models, focusing on usability, workload, and learning effectiveness in an engineering education context. A total of 184 first-year BSc engineering students voluntarily participated in an experimental activity. Participants were divided into three groups, each experiencing a different learning condition: slides-based, VR-based, and physical model-based. The study design ensured comparability across conditions using 3 out of 4 levels provided by the ICAP (Interactive, Constructive, Active, Passive) framework. Usability was assessed using the System Usability Scale, workload via the NASA Task Load Index, and learning outcomes through a task-based test. The study found no significant differences in test scores across the three conditions. However, participants in the VR-based and physical model-based conditions reported significantly higher usability and lower perceived workload compared to the slides-based condition. The VR-based condition provided an immersive environment while maintaining comparability in cognitive engagement. The findings demonstrate that VR can serve as an effective alternative to traditional learning methods, particularly for enhancing usability and reducing cognitive workload. However, its integration must be carefully designed to ensure cognitive engagement and optimize learning outcomes. This study highlights VR's potential in engineering education and underscores the importance of aligning tools with pedagogical goals.

Keywords: engineering education , learning , usability , virtual reality , workload

Technology is constantly evolving, changing how industries work by making processes more efficient. This shift, known as Industry 4.0, connects the real and digital worlds, allowing devices, people, and systems to communicate through the Internet. Key technologies include Internet of Things, big data, additive manufacturing, artificial intelligence, machine learning, augmented reality, and digital twins. This paper focuses on researching and implementing enabling technologies of Industry 4.0 by illustrating the design of DT models and AR experiences of a test bench with a motorized planetary gearbox. The case study starts from the CAD realization and assembly of all the components by using PTC Creo Parametric. Then, sensors are installed and connected to data acquisition devices to acquire and monitor input and output parameters of the system. Finally, AR experiences are developed using Vuforia Studio starting from CAD models of real components. The AR experience showed when the gearbox was not working properly, with the output shaft running about 13% slower than expected. Because of this, the gearbox was disassembled, and the inspection found some rusted parts inside. This paper presents the steps to create a DT model and AR interface using affordable hardware and software. The project shows how these tools can be used in industrial settings and education for activities such as hands-on learning, plant design, real-time monitoring, predictive maintenance, remote support, and sharing knowledge.

Keywords: Augmented reality , Digital twin , Gearbox , Industry 4.0 , Smart factory

The use of virtual reality technologies in the field of cultural heritage can play a central role in enhancing visitors' experience and accessibility of artifacts and artworks. However, the virtual museum (VM), other than being captivating, should be inclusive, ensuring equal participation and learning opportunities for all people, including those with disabilities. Accordingly, the integration of visual stimuli with tactile information by means of haptic technology can provide an innovative medium to experience VM contexts, enhancing the quality visitors experience, especially with reference to people with vision impairments or blindness, according to a universal design perspective. Though haptic devices could represent an asset for cultural heritage fruition and education, only a limited number of studies considered their application to enhance the VM visitors' experience so far, while their suitability for people with vision impairments or blindness is far from being properly investigated. Therefore, this study aims at bridging this research gap, illustrating the methods and results of a co-design process of a VM application integrated with a haptic interface involving people with vision impairments or blindness. The developed application consists of a multi-modal system that integrates haptic feedback with audio and visual information, geared toward providing the most comprehensive and engaging experience possible for users with vision impairments or blindness.

Keywords: Accessibility , Cultural Heritage , Guidelines , Haptic Technology , Leisure , Virtual Reality Technologies , Visual Impairment , VM Applications

Traditional surgical training methods often lack the immersive and interactive elements necessary for optimal skill acquisition. Virtual reality (VR) technology has emerged as a transformative tool in surgical education, offering realistic simulations that enhance technical proficiency, psychomotor skills, and cognitive planning. This paper presents a novel collaborative cross-platform VR framework that supports multi-user interaction, enabling trainees and instructors to engage in a shared virtual environment. Structured around a modular digital hospital, the system facilitates real-time training sessions, interactive knowledge sharing, and procedural simulations with integrated feedback mechanisms. A user study demonstrated a significant reduction in errors, improved precision, and faster task completion, underscoring the system's effectiveness in enhancing surgical training efficiency. Participants rated usability highly, highlighting the system's intuitive design, engagement, and potential for democratizing surgical education.

Keywords: Collaborative Learning , Digital Hospital , Medical Simulation , Multi-User VR , Surgical Training , Virtual Reality

In recent years, the application of ergonomics to workplace safety monitoring has gained increasing interest from companies and public institutions, allowing for the evaluation of the potential impact that dangerous situations may have on workers during their routine activities. This study presents a method for real-time monitoring of human physiological and motor responses to simulated workplace hazards during virtual reality safety training. The setup allows for precise measurements of both physiological and postural parameters during simulated scenarios. Moreover, a representative case study involving the sudden arrival of a forklift in a warehouse is presented. Five healthy participants were exposed to this scenario, with changes in heart rate variability and trunk posture being captured. The results demonstrate the effectiveness of sensor-based monitoring in detecting stress responses and postural adaptations to hazardous stimuli. This approach provides a basis for understanding human responses in simulated hazardous environments and may help to optimize safety training aimed at increasing workers' risk perception and improving overall workplace safety. Although based on a small sample, the findings provide preliminary insights into the feasibility of sensor-based monitoring during VR safety training.

Keywords: heart rate , kinematic analysis , markerless motion analysis , posture , safety , trunk , virtual reality

This study presents a multi-user virtual reality (VR) tool designed to enhance hands-on learning in engineering education through real-time sensorized digital twins. The motivation stems from the limitations of traditional laboratory settings, such as time constraints and restricted access to physical equipment, which can hinder practical learning. The developed environment allows multiple students, wearing VR headsets, to interact simultaneously with a real-time synchronized virtual model of an engine, replicating its physical counterpart at the Mechanical Engineering Laboratory of the Pontificia Universidad Católica de Valparaíso, Chile. This novel integration of VR and digital twin technology offers students a unique opportunity to observe engine behavior in operation within a safe, controlled virtual space. By bridging theoretical knowledge with practical experience, this approach deepens understanding of complex mechanical concepts while fostering the development of key technical skills. Additionally, the use of real-time data visualization and digital twins provides a safer, more interactive, and efficient alternative to traditional laboratory practices, overcoming constraints like time limitations and equipment availability. This innovative method introduces students to Industry 4.0 principles, encouraging data-driven analysis and informed decision making.

Keywords: combustion-less engine , digital twins , education , engineering education , Industry 4.0 , IoT , real-time sensing , virtual reality

Application of wearable robotic devices in training programs is gaining more and more interest. In the last few years, several training devices based on haptic and audiovisual stimuli have been developed to enhance training by stimulating proprioception. Transparency of these devices is a key parameter for the evaluation of their performance. In this study, we present the results of a transparency study of SIDE, a fully wearable 4-degree-of-freedom exoskeleton that provides haptic feedback to shoulder and elbow. The study examines transparency both kinematically and with respect to muscle activations using inertial sensors and surface electromyography, respectively. The study involved seven healthy subjects, who were asked to perform simple movements with their shoulder and elbow in two conditions (with and without an exoskeleton) and with three different masses. Our analysis, conducted using a repeated-measures ANOVA test, revealed that from a kinematic perspective, there were no observable differences between conditions. However, our findings showed greater muscle activation, especially for the anterior, middle, and posterior deltoids and the biceps brachii, when the exoskeleton was in use. At the conclusion of the experiment, subjective opinions of the participants were collected, revealing that they had not perceived any difference between the conditions.

Keywords: Biomechanics measurements , EMG , Exoskeleton , IMU , Surgeon training , Transparency

Technological advancements are profoundly reshaping industrial environments, particularly by introducing paradigms such as Industry 4.0 and Industry 5.0, prioritizing increased productivity alongside worker well-being improvements. Concurrently, the European Union reports a fast-aging population, reflected in the industrial workforce. Consequently, assessing the impact of emerging technologies across different age groups is crucial. This study employed an Immersive Virtual Reality (IVR) system to simulate a high-risk industrial scenario for training workers on safety and operational procedures. Fifty participants were divided into three age groups: young ranging from 19 to 33 years old, middle-aged ranging from 34 to 48 years old, and older ranging from 49 to 63 years old. The IVR system recorded execution times and errors, while subjective measures were collected using the User Experience Questionnaire, System Usability Scale, and Virtual Reality Sickness Questionnaire (VRSQ). The results show that younger participants committed significantly more errors but completed tasks faster, although this difference was not statistically significant. Self-assessment scores revealed no significant increase in VRSQ values across groups, while younger participants rated the system's hedonic quality significantly higher than the older group. System usability was rated substantially higher than the minimum acceptable threshold, with younger participants providing significantly better evaluations compared to older ones. This study highlights the importance of a human-centered design in IVR systems, complying with age-related needs to enhance usability. This approach ensures IVR technology in industrial training achieves optimal efficiency and effectiveness across diverse workforce demographics.

Keywords: Age-related performance , Immersive virtual reality , Industrial safety training , User experience metrics , Workplace accident prevention

Effective communication and stakeholder collaboration are vital for successful design reviews. Traditionally reliant on physical mediums, design reviews now predominantly use digital 3D models for their flexibility and cost-effectiveness. Recent advancements in extended reality (XR) technology allow for immersive interactions with 3D models, enhancing spatial understanding. However, research often limits the choice to XR or flat screens, overlooking task-specific needs. This paper proposes a methodology using functional modeling and activity theory to assess XR's suitability for various design review tasks. By categorizing tasks and analyzing functionalities, it guides the optimal use of XR and flat screens, enhancing design review effectiveness. Future research will empirically validate and refine this framework to support hybrid design review protocols, improving collaborative design processes. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

Keywords: Activity Theory , Asymmetric Collaboration , Design Reviews , Functional Modeling

The upcoming generation of smart, wearable, embedded, and ubiquitous technology paved the way to a new era of context-aware, intelligent mixed reality (MR) user experiences, as a mash up of separate advancements in key areas of MR, artificial intelligence (AI), and spatial computing. We sought contributions extending current boundaries of MR user experiences that addressed new methods, technologies, approaches, applications, case studies, and industrial showcases for novel insights, breakthrough designs, discussions, and developments in this rapidly evolving domain. This second chapter of the Special Issue presents three contributions in the field of MR user smart guidance. The first contribution is a sensor-rich MR application in the field of cultural heritage, offering innovative navigation for exploring the artworks. Rather than passively receiving information, visitors are actively guided and engaged in contents of interest. The other two propose the combination of MR technology with AI tools for task guidance in complex cognitive and emotionally demanding scenarios. These works clearly show the still undiscovered potential of the integration of these technologies, but also the limitations and challenges to be addressed by future research.

Keywords: Context-Aware , Embedded technology , Guidance system , Mash up , Mixed reality , Smart technology , Smart wearables , Spatial computing , Ubiquitous technology , Users experiences

The advent of virtual simulation and Augmented Reality has had a profound impact on industrial processes, enhancing operational efficiency and optimising production workflows. This paper presents a comprehensive study on the development and implementation of a Mixed Reality Lab designed for the assembly and disassembly of industrial products. The primary objective is to create an advanced and intuitive Virtual Reality (VR) environment that facilitates industrial operators' learning and reduces training time while minimising errors. The project encompasses the scanning and 3D modelling of industrial components using various technologies, including photogrammetry, structured light, laser scanning, and LiDAR. These techniques are evaluated for their precision and effectiveness in generating accurate 3D models. The VR environment is developed using Unity, incorporating features that support interactive and immersive user experiences. Detailed methodologies for the creation and refinement of point clouds, mesh generation, and virtual environment setup are provided. The assembly and disassembly processes are tested using a brake assembly as a case study, thereby demonstrating the system's ability to manage complex industrial tasks. The results indicate significant improvements in training efficiency and operational precision, with potential applications across various industrial sectors.

Keywords: Mixed reality , Simulation , Training , User-centred application

This paper describes how to create interactions between the virtual world and the medical environment to solve one of the problems frequently encountered during the design phases of operations, highlighting the importance of this project in the realm of Applied R&D + i for high-detail, patient-specific medical operations. In particular, rotations and translations required to solve valgus and varus problems of the tibia and femur are analyzed. Currently, prostheses are produced using non-specific software that requires the presence of an external operator. A virtual reality (VR) application to improve the interaction between the software and the surgeon, thus simplifying the prosthesis design process, is presented. The method proposed in this paper applies mechanical design to the medical field, starting from the principles of Industry 4.0 for human–machine interaction. Virtual Reality implements mechanical concepts such as the hinge and its function in virtual environments like Unity. This approach allowed us to limit the movement of an object in space to rotations around an axis defined by the end user, making these rotations ‘parametric', i.e. traceable to finite mathematical values. It was demonstrated that the design of wedge-shaped prostheses for realigning the tibia and femur during surgery has been thus simplified.

Keywords: Augmented reality , Parametric operation , Surgery planification , Training , Virtual reality

Nowadays, the technological maturity achieved by Extended Reality (XR) technologies allows to develop applications that foster positive emotions and promote personal growth. The scope of this work is to present the first results about a research project (BIOXRE - BIOphilic design of Extended Reality working Environments) focused on the application and evaluation of the biophilia hypothesis of Positive Computing in virtual workplaces. In the literature, there is effectively evidence that biophilic design improves human wellbeing. However, only a few studies evaluated its effectiveness in improving operators' wellbeing in the real workplace. For the first time, BIOXRE aims to exploit the biophilic design to XR applications supporting procedural tasks. The goal is to improve the wellbeing of human operators without affecting their performance in accomplishing manual tasks supported by XR visualization. The outcome of the project will be to extract guidelines for the spatial augmentation of real workplaces, fostered by the biophilic design, that will derive from a well-structured user evaluation in the target industrial scenario.

Keywords: biophilic design , Industry 5.0 , Positive Computing

This study aims to explore the use of Augmented Reality (AR) visual assets to convey procedural instructions, specifically for conveying information about component orientation. We focused on assembly scenarios where no affordance is provided for orientation while maintaining a consistently high affordance for how components are mounted. This information is recurrent in tasks where users are familiar with components that fit together without needing specialized tools but lack knowledge of the specific orientations required for the assembly. A typical example is placing rubber gaskets that fit smoothly into grooves but where no markings indicate the correct sealing side. We evaluated six different AR presentation modes for conveying component orientation: image, video, static side-by-side product model, animated side-by-side product model, static in-situ product model, and animated in-situ product model. The literature provides no clear agreement on which is the most effective. To fill this gap, we conducted a user study with 36 participants, measuring completion time, accuracy, and cognitive load across the six AR presentation modes. We also analyzed how users interacted with each of them and collected user subjective feedback. Our findings revealed that the animated side-by-side product model ensures better completion time, demanding less cognitive load and being favored by users.

Keywords: assembly , Augmented Reality , authoring , instruction , orientation , visual asset