Human factors and ergonomics

This work analyzes the impact of subjective factors on users' immersive experience, while using glove-based handling devices as input system. A user-study has been conducted on a Virtual Training framework, evaluating usability and mental effort perceived with such devices.

Keywords: Frustration , Gloves , Handling devices , Usability , User study , Virtual Training

The creation and management of content are among the main open issues for the spread of Augmented Reality. In Augmented Reality interfaces for procedural tasks, a key authoring strategy is chunking instructions and using optimized visual cues, i.e., tailored to the specific information to convey. Nevertheless, research works rarely present rationales behind their choice. This work aims to provide design guidelines for the localization of in-view and not occluded components, which is recurrent information in technical documentation. Previous studies revealed that the most suited visual cues to convey this information are auxiliary models, i.e., abstract shapes that highlight the space region where the component is located. Among them, 3D arrows are widely used, but they may produce ambiguity of information. Furthermore, from the literature, it is unclear how to design auxiliary model shapes and if they are affected by the component shapes. To fill this gap, we conducted two user studies. In the first study, we collected the preference of 45 users regarding the shape, color, and animation of auxiliary models for the localization of various component shapes. According to the results of this study, we defined guidelines for designing optimized auxiliary models based on the component shapes. In the second user study, we validated these guidelines by evaluating the performance (localization time and recognition accuracy) and user experience of 24 users. The results of this study allowed us to confirm that designing auxiliary models following our guidelines leads to a higher recognition accuracy and user experience than using 3D arrows.

Keywords: Augmented reality , Authoring , Auxiliary model , Localization

Mixed Reality (MR) technology has gained popularity in the manufacturing industry over the last few decades. In the maintenance field, it helps workers in document analysis and decision-making during operations. While numerous studies have demonstrated the empirical benefits of MR, few have examined its applicability in a real industrial context. Among them, many focus on user performance. The novelty of our work is to evaluate mainly the acceptance of MR technology by experienced technicians using smart glasses for maintenance tasks in a real industrial context. We conducted a user study involving 7 workers who were asked to follow the instructions provided by an MR Technical Documentation (MRTD) developed considering authoring guidelines already validated in the literature but only in a laboratory context. The industrial operators performed both navigation tasks within the menu of the MRTD and a disassembly task, following the instructions displayed on the smart glass. The evaluation in the real working scenario showed that MRTD is highly appreciated by workers even if they have no previous experience with smart glasses. These results allow us to confirm the goodness of the design guidelines followed for the authoring of the MRTD.

Keywords: Industrial Operator Support , Mixed Reality , Smart Glasses , Technical Documentation , User Acceptance

The biophilic design of virtual workplaces consists of introducing additional natural elements in the virtual environment (VE) with respect to those needed for the main task. It has received increasing attention in recent years, and an increasing number of studies are showing that exposure to biophilic elements in an immersive VE produces positive effects on human well-being. However, in the literature, there are no guidelines about the setting of the different variables of biophilic design in a VE. In this work, we investigated one of these variables, i.e., the effect of the animations of biophilic elements, formulating the following research question: how do animations of biophilic virtual elements affect user attention while performing a working task? We carried out an experiment in which users performed two levels of difficulty of the n-Back cognitive test in three VEs: two identical biophilic VE, one with all static elements and another one in which some of these elements were animated, and an additional empty VE used as a baseline. Performance measurements, eye-tracking measurements, and subjective measurements were collected from 24 users. We found that introducing animations of biophilic elements does not affect user performance in the cognitive task. Furthermore, we found that users' gaze remains fixed on the main task for more than 94% of the time. However, the use of animations does not bring added value to users in terms of user experience, whereas it causes an increase in perceived distraction and mental effort.

Keywords: Animations , Biophilic Design , Positive Computing , Virtual Reality

The use of eXtended Reality (XR) technologies, including augmented reality (AR), virtual reality (VR), and mixed reality (MR), has become increasingly popular in museums to enhance the visitor experience. However, the impact of XR technologies on Learning Performance in the context of archeological museums needs to be better understood. This study aims to investigate the relationships between Usability, Presence and Learning Performance by developing XR experiences showcasing archeological artefacts and conducting user testing to evaluate their effectiveness. A laboratory test is conducted to compare a VR application with a mobile AR one, presenting the digital models of five archeological findings. Descriptive statistics are used to compare the two case studies, providing valuable insights into the impact of XR technologies on the visitor experience from a learning perspective. The study confirms that Usability has a more significant effect on learning than Presence and can help designers and museum managers better understand the factors contributing to a successful XR experience. The findings suggest that while Presence is an important factor in improving visitors' experience, Usability should be the priority when designing XR experiences for museums.

Keywords: Cultural heritage , Technological Benchmarking , XR Technologies

The concept of sustainability concerns the ability to satisfy current needs without compromising the possibility for future generations to satisfy their own needs. Over the years this concept turned out to be an essential theme for many industries because of a spread and heightened sensitivity towards environmental protection and social responsibility. Nevertheless, every firm still needs to guarantee the economic viability of its actions and retain its competitive advantage over competitors to remain in the market. This idea corresponds to the triple bottom line approach, according to which the business performance should be monitored from three perspectives, namely economic, environmental, and social. From one side sustainability means the integration of multiple practices, whereas on the other side, the current globalized and competitive economy requires enterprises to combine sustainability with practices of Industry 4.0 to contribute to Circular Economy objectives. The aim is to make choices that improve all three aspects. This work proposes an approach able to involve all three pillars of sustainability and the forefront tools to evaluate them. The case study presents the improvement of the manufacturing process for kitchen furniture. The aim was to create a smart working environment able to increase productivity and mitigate ergonomic risks ensuring a reduced environmental impact. Four parallel manual assembly lines were replaced with one semi-automated line, in which some specific workstations can adapt the product position to the operator's anthropometric measures. The re-design of the workplace allowed both the reduction of out-of-quality pieces and the enhancement of worker well-being. The main results show the achieved optimization for each pillar.

Keywords: Lifecycle analysis , Sustainability , Sustainable manufacturing , Three pillars , Worker well-being

The transition to Industry 5.0 emphasizes the human-centric perspective and pushes for ergonomic risks prevention and mitigation. The diffusion of the production paradigms of mass customization and mass personalization also increases the need for methods and tools to support workers in manufacturing activities. The growing number of product variants requires a higher cognitive load and increases the likelihood of human errors. Work instructions become fundamental, as well as their digitalization. The technologies enabling industry 4.0 have opened up new scenarios for the use of this information, from extended reality to digital assistance systems. This work deals with the human-centered redesign of a workstation for the wire harness assembly with the aim of mitigating the ergonomic risks for operators, both physical and cognitive. Four different scenarios for using the work instructions were implemented and tested: paper-based instructions, workstation display, mixed reality application usable with a head-mounted display, and augmented reality application that only requires a projection system. The experimentation involved user experience evaluation, performance assessment, and objective postural analysis through inertial sensors.

Keywords: ergonomics , human-centered manufacturing , industry 5.0 , mixed reality , work instructions

With the rising concept of Industry 5.0, the worker's needs and well-being are placed at the center of the production process. This new human-centered approach will let the industrial sector reach many social goals besides employment and growth. Working in an unhealthy workplace can lead to stress, frustration, and worry. Moreover, the operator's well-being and performance could be affected and compromised by high mental demand due to the increase in production complexity. As a result, work-related stress has grown to be one of the major health issues, and new tools and methods for stress detection need to be researched and developed. However, the detection and assessment of mental stress in real settings is still an open challenge. Within working contexts, the most widespread assessment methods are subjective evaluations based on self-rating questionnaires whereas objective evaluations or multi-modal approaches are mainly used in controlled environments. This paper proposes a systematic review of the research works related to stress detection on-field in working environments. Although there are many research papers on stress detection in controlled laboratory conditions, the number of studies examining this topic in a working context is very limited. A descriptive and detailed analysis provides an extensive overview of the current state of the art. Finally, the paper addresses open issues, challenges, and future research directions for stress detection in working environments.

Keywords: Human factors , Human-centered manufacturing , Industry 5.0 , Stress detection , Work-related stress

The increasingly high rate of work-related musculoskeletal disorders among workers is leading to the necessity for innovative systems for risk assessment. Although traditional methods for physical ergonomics assessment, based on the observation of working activity and manual compilation of standard analysis, are easy-to-use and very widespread, they provide a subjective evaluation and require a well-trained ergonomist. These factors lead to the requirement for objective evaluation and the new technologies can support the development of real-time risk assessment tools. Nowadays, the main technologies used for ergonomic assessment are inertial sensors and markerless depth cameras. Despite their reliability, the former are intrusive and expensive. This paper aims at comparing the accuracy and reliability of (1) wearable inertial sensors (as a reference) and (2) a markerless system composed of three RGB-D cameras. Using Machine Learning algorithms and open-source libraries, the system can track and record the operator movements and postures rebuilding the human skeleton. The proposed system has been tested in the laboratory where different static postures have been recorded. The preliminary experimentation provided satisfactory results in terms of accuracy and reliability.

Keywords: Ergonomics , Inertial Sensors , Markerless System , Motion Capture , RGB-D Cameras

In the last decade, museums and exhibitions have benefited from the advances in Virtual Reality technologies to create complementary virtual elements to the traditional visit. The aim is to make the collections more engaging, interactive, comprehensible and accessible. Also, the studies regarding users' and visitors' engagement suggest that the real affective state cannot be fully assessed with self-assessment techniques and that other physiological techniques, such as EEG, should be adopted to gain a more unbiased and mature understanding of their feelings. With the aim of contributing to bridging this knowledge gap, this work proposes to adopt literature EEG-based indicators (valence, arousal, engagement) to analyze the affective state of 95 visitors interacting physically or virtually (in a VR environment) with five handicraft objects belonging to the permanent collection of the Museo dell'Artigianato Valdostano di Tradizione, which is a traditional craftsmanship museum in the Valle d'Aosta region. Extreme Gradient Boosting (XGBoost) was adopted to classify the obtained engagement measures, which were labeled according to questionnaire replies. EEG analysis played a fundamental role in understanding the cognitive and emotional processes underlying immersive experiences, highlighting the potential of VR technologies in enhancing participants' cognitive engagement. The results indicate that EEG-based indicators have common trends with self-assessment, suggesting that their use as ‘the ground truth of emotion' is a viable option.

Keywords: craftsmanship , cultural heritage , EEG , user engagement , Virtual Reality , XGBoost

This paper explores how the examination of additively manufactured auxetic componentry can be applied in human-centred design settings with particular focus on biomedical products. Firstly, the design applications of auxetics are detailed followed by a review of the key problems facing practical researchers in the field with the treatment of boundary conditions identified as a key issue. The testing setup that is then introduced utilises a novel method of part mounting and facilitates optical analysis and real-time force–displacement measurements. A study is advanced that analyses three different auxetic structures (re-entrant, chiral, and semi-rigid), a set of samples of which were additively manufactured in flexible TPU material. A range of parameters were varied across the three designs including interior geometry and wall thicknesses in order to demonstrate the effectiveness of the setup for the examination of the different structures. The results from these examinations are subsequently discussed and a number of suggestions made regarding how this kind of analysis may be integrated into novel design development workflows for achieving human-centred biomedical devices which often require detailed consideration of ergonomic and usability factors.

Keywords: Auxetics , Biomedical applications , Human-centred design , Mechanical testing

In the context of Industry 4.0 and Industry 5.0, the introduction of collaborative workplaces, where humans and robots work together, represents a growing trend to improve the productivity, adaptability, and flexibility of production plants. Indeed, human–robot collaboration (HRC) is a very deepened topic in the scientific community and the designing of collaborative workplaces is a challenging issue due to the high level of complexity and multidisciplinary of its features. This work tackles the complexity of collaborative workplaces and proposes a structured framework to support strategic decisions in designing. A multi-level designing framework is proposed as a supporting tool for designers. Within five domains of collaborative robotics, the elements of a collaborative workplace are identified and proposed in a framework in order to better consider human safety and working conditions during the designing process. A decomposition matrix and an adjacency matrix are used to develop a multi-level designing workflow. Finally, an interactive tool is presented, named “Smart Graph Interface” (SGI), to read and exploit the contents of the framework. The SGI is applied to three case studies from the literature, to spread out principal outcomes in terms of applicability and robustness.

Keywords: Collaborative workplace design , Graph theory , Human–robot collaboration , Multi-level design , User interface

In recent decades industrial development has led to increasingly sophisticated machinery and systems, which require complex maintenance routines. Consequently, maintenance operators may not have the sufficient skills to perform recovery procedures properly and quickly, so that the need of assistance from the manufacturer's after-sales service or companies specialized in maintenance services. Such actions usually lead to very long recovery times, high maintenance costs, and a temporary drop in production. In this scenario, we should consider that Industry 4.0 is making available innovative technologies, such as Augmented Reality (AR), suitable for improving the skills and competencies of operators without burdening their cognitive load, and consequently wellbeing. However, technologies must be selected, designed, and used according to the users' needs to be effective and useful. The paper presents a user experience (UX)-driven methodology for designing user-centric AR applications for complex maintenance procedures. The methodology was applied to a real industrial case concerning the management of CNC machines in a plant producing tractors components, where a smartphone-based AR application was designed and tested with users. The satisfactory results highlighted the potential benefits of AR in industry and specifically in maintenance.

Keywords: Augmented Reality , Industry 4.0 , Maintenance , Operator 4.0 , User experience design

Modern automated production systems (e.g., automatic machines, assembly lines, robotic cells) are typically governed by dedicated industrial controllers, such as Programmable Logic Controllers (PLCs), which supervise and coordinate the process by exchanging I/O data, sequencing tasks or triggering actions with the involved automation modules. Different solutions have been developed to offer an intuitive Human-Machine Interface (HMI) programming to the user, based on PLC HMI editors, according to vendor-specific programming languages. However, in the current industrial practice, user interfaces (UIs) are usually generated by software specialists and far from adopting any user-centered approach. As a result, the generated UIs are poorly usable and hard to understand for end users (e.g., operators), diverging from Industry 5.0 ideas that put humans at the center of the modern factory design. In this context, the present paper aims at exploring how the adoption of User eXperience (UX) driven approaches can benefit the design of industrial PLC UIs, reflecting on advantages and limits, and transdisciplinary perspectives. A case study utilizing Beckhoff TwinCAT as PLC environment and Adobe XD as UX design tool is examined and discussed.

Keywords: Human-machine interface , Programmable Logic Controllers , User experience , User interface , User-centered design

Due to the rising digitalization in the past few years, even more data can be collected from smart products and sensors to describe the real world, goods, environments, and newly humans including those mutual interactions. Digital twin (DT) has become a key word in engineering, society, and medicine, which is also a hot topic in research for creating virtual data-driven replicas of real objects and simulating their behaviors to predict and optimize the entire system functioning. DTs can mirror the physical entities throughout their lifecycle and create real-time connections between the physical and virtual worlds to monitor and control physical objects from any location. Physical objects can be any living or non-living object, such as humans, machines, robots, cars, buildings, plants, food, or economy. Numerous papers related to DT in various industries have been presented, but very few are focusing on the human-related aspects and the quality of the human machine interaction. In this context, how to shape a human-centric digital twin (HCDT)? The paper states the needs of a human-centric approach in the design and development of DT and presents a set of significant applications of HCDT in different fields, from industry to medicine, from economics to society, discussing the positioning of the HCDT concept in the landscape of transdisciplinary engineering, which is also subject of a workshop during the conference.

Keywords: Digital Twin , Human-centric approaches , Human-machine interaction , Transdisciplinary Engineering

Nowadays, logistics is increasingly becoming a crucial process in the modern factories, and numerous companies are paying growing attention to the continuous improvement of quality and efficiency of logistic processes. Although Industry 4.0 concept introduced new digital technologies and led to high degree of automation of industrial and logistic systems, many tasks still rely on human work, especially in the warehouse. As a consequence, the consideration of the operators' needs is definitely a key topic to guarantee high quality work performance, according to Industry 5.0 paradigm. In this context, the quality of the training procedures is fundamental to speed up the knowledge transfer and empower operators through the use of digital technologies. This paper presents the development of a novel training methodology based on Augmented Reality (AR), promoting a learning-by-doing approach to enhance both operators' satisfaction and process efficiency and flexibility. A dedicated AR application has been developed for a spare parts warehouse of a large enterprise operating in the agriculture and construction vehicles sector, according to a User-Centered Design (UCD) approach. Results from field testing showed how the AR application is positively rated by the operators, guaranteeing high user satisfaction, and limiting the training effort.

Keywords: Augmented Reality (AR) , Training , User-Centered Design (UCD) , warehouse Operation

Total knee arthroplasty (TKA) is the surgical procedure of choice for end-stage osteoarthritis. Even if it is widely performed, there is still dissatisfaction with the surgical procedure in about 20-30% of patients. Factors such as malalignment of the implant and the size of the components have been reported as the most common reasons for post-operative complaints. Custom-made prostheses have been introduced to replicate each individual joint geometry and kinematics. In this study, a novel approach is proposed to automate custom-made knee implant design. The aim is to create a pipeline, where customized implants can be designed automatically for a large number of patients, reducing the time for design. Firstly, a manual procedure for designing the implant is defined. The lower part of the femur is extruded with a thickness that matches with the natural anatomy of the patient and cut planes are used to design the customized femoral implant. Then, an automatic procedure is developed. For the purpose, a statistical shape model of femur, based on 33 patients, is created and employed. The procedure is tested with 5 study cases showing the potential of the methodology. Results will be furtherly validated on a larger scale.

Keywords: 3D Modelling , Customization , Human Modelling , Personalized , Statistical Shape Model , Total Knee Arthroplasty

Logistic activities can cause long-term musculoskeletal problems due to repetitive and incorrect movements, heavy loads, and uncomfortable positions. Ergonomic evaluations are conducted to prevent these risks, optimize workstations, and work processes. Some studies use automatic evaluation of ergonomic indices or frameworks for optimizing workstations and logistics reorganization. However, optimization is often disconnected from real-world case studies. This research work validates a new approach that integrates an automatic ergonomic evaluation and optimization in real-world scenarios, comparing this analysis with traditional manual evaluation method. Our approach is applied to a real logistics case study using a wearable motion capture system and an interactive interface that displays the Digital Twin of the analyzed task. Results show that our approach provides a more accurate evaluation of the ergonomics and an evident time-saving.

Keywords: Ergonomics , Optimization , Warehouse Logistic

With technological innovation and advancements, especially in autonomy, battery and digitization, the future of air transport and mobility is transiting towards a broader spectrum of Advanced Air Mobility (AAM) and Urban Air Mobility (UAM). UAM envisions safer, faster, and more sustainable air mobility for smarter cities and urban environments including passenger transport and goods delivery. Nevertheless, this concept is still considered extremely breakthrough and several technological and operational aspects are mostly undefined. In this context, a comprehensive approach to AAM/UAM may be to adapt cutting-edge technologies in developing sustainable framework and Human-Machine Interfaces (HMIs) in order to realize the challenges, benefits, and conditions of such transport system in advance for future safer, more reliable and globally approved operations. One of the technologies that can contribute to accelerate advancements through human centred simulating UAM processes and operations is XR (eXtended Reality). This paper presents the early steps of a multidisciplinary study performed under the framework of PNRR (Piano Nazionale di Ripresa e Resilienza) and MOST (Centro Nazionale Mobilità Sostenibile) project in analyzing the perspectives of XR based HMIs for UAM paradigm and potential AAM/UAM use case scenarios that can be simulated with XR in view of attaining efficient and effective future solutions. Furthermore, the work introduces the state-of-the-art overview on XR facilitated UAM applications and considers prospective potential use cases that can be developed through PNRR research study in demonstrating XR as an enabling technology in promising areas of the UAM framework. © 2023, Association of American Publishers.

Keywords: Advanced Air Mobility , Extended Reality , Human Machine Interfaces , Immersive Technologies , U-Space , Unmanned Aerial Systems , Urban Air Mobility

Autonomous vehicles companies are awakening of cutting-edge technology by offering self-driving cars, however, customers' acceptance and trust of this high-tech product has become a significant open challenge in the world. It can be expected that autonomous vehicles (AVs) ameliorate traffic flow, lessen accidents and injuries, and save the time on travel in addition to people's life. Despite the increment of human replacement by the artificial intelligence in various industries and artifacts, most customers have not convinced with this big revolutionize transportation yet. This paper presents an experiment that evaluated the impact of personality, affinity to technology and demographics on human's trust in autonomous vehicles. 19 engineering students did participate in the experiment by using an autonomous vehicle with level 2, that had automated speed and trajectory maintenance, but without automatic detection for obstacles, objects or events while driving. First, the AV programmer explained its function and information about the track to all participants. Then, they were asked to answer to 9 questions of Affinity for Technology Interaction (ATI) scale, 17 demographic questions, and 10 questions of Big Five Questionnaire (BFQ). Afterwards, all participants rode 10-minute path in a pre-defined rout with the accompaniment of the AV programmer to control probable dangerous situations. Finally, they completed Trust in Automation Scale questionnaire. Gathering data was analysed using IBM SPSS 26. The mean and standard deviation were calculated for descriptive data and the Spearman for analytical data. The results showed a behavioural split (50/50) among people having and not having complete confidence in the autonomous vehicle. Nervous people trust the AV less than others, like people with little or no experience in using an AV. As well, the more transparency we had in the AV's behaviours and presenting information about it, the more trust and security was perceived by participants. People with high level of technology affinity experienced more trust in the AV, as the effect of frequent exposures with an AV. It's worth mentioning that females are more conservative and prefer to trust an AV less than males. The results indicated that various variables could affect people's trust in AVs. Obviously, changing people's demographics and some aspects of personality seem to be impossible most of the times, while as approved by other recent studies, their affinity to technology, as a new type of personality, can change or be changed. As the results showed, it is recommended to AVs companies to design a good system in the vehicle, in order to present all information to passengers clearly. In addition, if some conditions are provided that people can test these vehicles and know more about their functions in detail, their trust will definitely increase significantly.

Keywords: Autonomous vehicle , Personality , Technology affinity , Trust , User experience