Human factors and ergonomics

The scarce availability of water in highly populated cities is about to become a social problem. While the water service companies work on improving the distribution network in order to reduce losses, it is evident that one of the main problems is due to an excess of use of this resource by users. This consumption is relatively controlled when excessive consumption is clearly associated, in the consumer mind, with high costs. However, when users are in public places they tend to consume water because of a loss of correlation with costs. In this paper, we describe the design of a device to be installed in public environments, which aims to reduce the consumption of water. The device measures in real time the flow of water and sends the user visual and sound information trying to create a link between consumption and costs. The device has been installed in a university campus bathroom and has been tested. Test results show a reduction in water consumption, especially in the interactive prototype approach compared to the conventional treatment. Further modifications for future development of the interactive device is also discussed.

Keywords: Design for sustainable behavior , Multisensory product experience , Sustainability , User centred design , Water conservation

A bursting number of achievements in the autonomous vehicle industry have been obtained during the past decades. Various systems have been developed to make automated driving possible. Due to the algorithm used in the autonomous vehicle system, the performance of the vehicle differs from one to another. However, very few studies have given insight into the influence caused by implementing different algorithms from a human factors point of view. Two systems based on two algorithms with different characteristics are utilized to generate the two driving styles of the autonomous vehicle, which are implemented into a driving simulator in order to create the autonomous driving experience. User's skin conductance (SC) data, which enables the evaluation of user's cognitive workload and mental stress were recorded and analyzed. Subjective measures were applied by filling out Swedish occupational fatigue inventory (SOFI-20) to get a user self-reporting perspective view of their behavior changes along with the experiments. The results showed that human's states were affected by the driving styles of different autonomous systems, especially in the period of speed variation. By analyzing users' self-assessment data, a correlation was observed between the user “Sleepiness” and the driving style of the autonomous vehicle. These results would be meaningful for the future development of the autonomous vehicle systems, in terms of balancing the performance of the vehicle and user's experience.

Keywords: Autonomous vehicle , Driving style , Human behavior

More and more modern digital applications allow users to make experiences that elicit their senses. More traditional applications allow users to make visual and sound experiences. Recently, the sense of touch has been introduced to enrich the users' experiences with digital worlds. The sense of smell is equally important for enriching and making the experiences engaging, but has been mostly neglected so far, mostly because of the limited knowledge about olfaction and of olfactory technologies. This chapter presents a methodology for the development of applications including multisensory user experiences based also on the sense of olfaction. The methodology has been used and tested for the development of applications in various sectors, which are reported in the chapter.

Virtual, Augmented and Mixed Reality technologies are more and more getting attention from tourism researchers and professionals, because of their recognized potential to support marketing activities. The paper describes the development of a multisensory environment thought for a travel agency, which combines visual, auditory, tactile and olfactory stimuli. The idea is to develop an experience able to provide a virtual preview of the desired holiday destination, resulting in both an attractive experience for the customer and an effective way to increase sales. A case study about the multisensory experience of a walk on Italian Alps has been developed. The multisensory experience is based on a video streaming, recorded in the real environment, synchronously matched with a haptic interface. The haptic interface is made up of a pair of slippers provided with actuators, and also an actuator positioned on the customer trunk, used to reproduce the feeling of a snowball hit. Moreover, an olfactory display is also used to provide pine smell during the walk. During the experience, the user is sitting on a yoga ball, whose inclination allows him/her to start and stop the multisensory virtual experience.

Keywords: Multisensory simulation , User experience , Virtual prototyping , Virtual tourism

Recently, an increasing need for sophisticated multimedia analytics tools has been observed, which is triggered by a rapid growth of multimedia collections and by an increasing number of scientific fields embedding images in their studies. Although temporal data is ubiquitous and crucial in many applications, such tools typically do not support the analysis of data along the temporal dimension, especially for time periods. An appropriate visualization and comparison of period data associated with multimedia collections would help users to infer new information from such collections. In this paper, we present a novel multimedia analytics application for summarizing and analyzing temporal data from eye-tracking experiments. The application combines three different visual approaches: Time∘diff, visual-information-seeking mantra, and multi-viewpoint. A qualitative evaluation with domain experts confirmed that our application helps decision makers to summarize and analyze multimedia collections containing period data.

Keywords: Data visualization , Multimedia analytics , Multimedia application , Period data

Previous studies have failed to provide a comprehensive view on the value perception of green products. The present research takes up this challenge through an experiment in which 43 participants have interacted with and evaluated 40 products-20 baseline products and 20 green products of the same categories. The experiment included both self-assessments to monitor conscious evaluations of the products and biometric measurements (Eye-Tracking and Galvanic Skin Response) to capture unconscious aspects. The results show that different forms of perceived value emerge clearly. Green products, for which participants required greater efforts in the search for relevant information, boost the value attributed to creative solutions still believed of high quality. This effect is significantly more evident for participants showing remarkable interest for sustainability issues. Conversely, alternative products feature greater value perception because they are acknowledged to be functional and reliable.

Keywords: Attitude-behavior gap , Biometric measures , Creativity , Eco-design , Estimated price , Eye-tracking , Green products , Principal component analysis , Value perception , Willingness to pay

Biometric devices and especially eye tracking systems have been used in various sectors such as neuroscience, clinical research, training and learning, linguistics, biomechanics, ergonomics and market research. So far, there are only a few applications of eye tracking in industrial environments such as engineering design and manufacturing or assembly. The aim of this research is to review why and to what extent biometric devices such as eye tracking systems can be used in industry. The research provides an overview of the state of the art in using these technologies in industrial engineering with a special focus to design and manufacturing. In addition, this paper briefly describes two currently running test series of the research team to investigate the usability of these systems in industrial engineering.

Keywords: assembly , assistance systems in production , biometric devices , biometric measurement , design , eye tracking , industry 4.0 , manufacturing

The outreach of application domains for Additive Manufacturing (AM) is expanding and end-use products represent their next frontier. Contextually, design methods are developed for exploiting the unique AM capabilities. They largely benefit from the knowledge about peculiarities, constraints and technical performances of the various AM processes and devices. However, while the mechanical properties of objects created with AM are widely studied, there is lack of research on emotional and perceptual aspects. This is of great relevance in the mentioned perspective of employing AM for end-use products. The paper aims to elucidate which perceptual mechanisms are activated when a user observes an object generated with AM instead of traditional technologies. An experiment has involved 43 participants who have evaluated ten pairs of objects, constituted by a commercial product and a replica made with Fused Deposition Modelling. Testers have answered a questionnaire, as well as their visual behavior has been recorded with eye-tracking glasses. Based on results, replicas suffer from poor attractiveness and especially low perceived quality. They have also given rise to more careful exploratory behaviors because they likely require a lengthier examination for testers' assessment or they arouse curiosity. It can be inferred that Fused Deposition Modelling does not exhibit sufficient accuracy to achieve acceptability with reference to everyday products. Nevertheless, it is also deemed that limited improvements might compensate for the perception of technical unsuitability this technology engenders. This can be verified by repeating the experiment with more sophisticated and precise AM devices.

Keywords: Design for additive manufacturing , End-use products , Eye-tracking , Fused deposition modelling

The fourth industrial revolution aims at digitizing the production, supply and distribution chains. In the course of this, an optimization of the processes should take place, through which the productivity can be increased, and the error rate can be minimized. Not only the production lines and the production processes are in the focus, but also the role of the employee himself becomes more and more important, for whom the working environment has to be made more comfortable and more pleasant. Technological opportunities also consist of biometric measurement techniques, which include Eye Tracking as technology. In order to achieve the goals of Industry 4.0, Eye Tracking can be used to design the working environment of the future individually to the employee. The article discusses the benefits and critical points of Eye Tracking for optimizing assembly processes in production. The results of tests with this technology in the laboratory and in a small and mediums sized company are critically examined.

Computer aided technologies (CAT) are becoming an indispensable instrument to design, improve and manufacture new products and services. Digital human modelling (DHM) systems allow to simulate the Human-artifact interface and to evaluate, in early step of design process, the ergonomic performances of new products or workplaces. In particular, for products that have to be used in a “constrained” workplace, different tasks and activities are associated with different postures. The aim of this study is to investigate the influence of anthropometric characteristics and expectations on the postural comfort perception through the CAT/DHM systems, while using four office devices: desktop computer, laptop computer, tablet and smartphone. A statistical sample of healthy students was selected and their anthropometric characteristics were measured. The postures assumed by the participants were gathered in a not-invasive way by cameras. The angular detection was performed directly on snapshots by using Kinovea® software. Human joints' an-gles were used for the virtual-postural analysis, through DELMIA® software. The evaluation of postural comfort was obtained in two ways: CaMAN® software developed by the researchers from the Department of Industrial Engineering in Salerno (Italy) was used to calculate the objective comfort indexes while an appropriate questionnaire, given to subjects during the devices usage, was used to evaluate the subjective com-fort indexes. The results of analyses show a difference between subjective and objective postural comfort indexes for all the devices: this difference has been associated to the expectations.

Keywords: Comfort evaluation , Computer aided technologies , Expectations , Not-invasive postural analysis , Office devices

Currently, the word ‘comfort' is often used in relation to the marketing of products such as chairs, cars interiors, clothing, hand tools and even airplane tickets. In this field of research, the aim of this study is to investigate the influence of spinal posture on postural (dis)comfort perception; the test case is the analysis of the interaction between humans and vending machines for purchasing food or beverages. A statistical sample of 20 healthy students (subjects) performed the required tests, with each participant asked to take a product from three different vending machines (snacks, drinks and coffee). The subjects' postures were acquired non-invasively using cameras; software and instruments for virtual prototyping were used for posture analysis and interaction modelling, both questionnaires (subjective) and comfort-analysis software (objective) were used to rate the perceived (dis)comfort. The results obtained from simulations and questionnaires were compared, and a method to weigh the effect of the perceived spinal discomfort on overall postural (dis)comfort was proposed. These results reveal a good correlation between subjective perception and objective evaluation obtained through simulations, confirming the validity of the proposed method.

Keywords: Comfort evaluation , Information fusion , Non-invasive postural analysis , Spine discomfort , Vending machines

Everyday life is increasingly rich in man-machine interactions and new challenges in user interface design arise. In particular, it emerges the need of adaptable solutions that learn from the user's behavior to improve their experience. In this context, the paper aims to redesign an existing UI to make it an Adaptive System. The introduction of an adaptive module allows finding the optimal interface features combination based on the user profile and previously interactions. The experimentation results demonstrate the adaptability and versatility of the proposed application by evaluating the user satisfaction and the perceived adaptability with respect to the native application.

Keywords: adaptive interfaces , household appliances , usability , user-centered

In manufacturing context, social dimension is often neglected. With Industry 4.0, companies focus more on technologies and data. However, human continues to play a key role in cyber-physical systems and company growth. This work proposes a method to help the company to evaluate workers' experience and identify the optimal solution to improve workers' well-being and company performance. It starts from personalized social analysis within a production plant to identify ergonomics problems and intelligently suggest effective corrective actions. The latter are selected achieving the best trade-off between social, economic and productive aspects. Three case studies are proposed to validate the method.

Keywords: Human factors , Industry 4.0 , Manufacturing systems , Social sustainability

The purpose of this study is to research if a headrest benefits the comfort of the passenger and lowers muscle activity in the neck when sitting in a reclined (slouched)posture while watching in flight entertainment (IFE)in an aircraft business class seat. No significant differences in muscle activity in the musculus sternocleidomastoid and musculus trapezius pars descendant were found between the conditions with headrest and without headrest. A significant difference in expected comfort rating was found. Subjects indicated they expect to experience more comfort with a headrest when watching IFE for a duration of two movies during a long-haul flight. This study also found a significant difference in posture. In the condition without headrest the head was more upright compared to the condition with headrest. The lack of significant difference in muscle activity and the significant difference in posture may indicate that humans tend to look for a head position that is neutral, in the sense of minimal muscle effort. This study shows that the use of a headrest may benefit the comfort experience of the passenger during flight. However, further research is necessary on the design of the headrest and the long-term effects of head support on comfort, discomfort, muscle activity and fatigue for watching IFE in a slouched posture.

Keywords: Aircraft seat , Comfort , EMG , Headrest , Neck angle , Posture , TV

BACKGROUND: Several comfort perception models have proposed an objective method to evaluate 'effects in the internal body' and 'perceived comfort'. Postural comfort is one aspect of comfort/discomfort perception, and this current work adds to existing knowledge toward a more objectified posture evaluation for comfort. OBJECTIVE: The authors have used the concept of Range of Rest Posture (RRP), as proposed by Apostolico et al. The study focused on the identification of RRP within the Comfort Range of Motion (CROM) for lower limbs. METHODS: The proposed method is based on extensive experimental work involving 114 healthy individuals (59 males and 55 females) ranging from 20 to 40 years old. The age range was narrowed to avoid an age-clustering of results due to inhomogeneity of the statistical sample. Data were processed using statistical methods for identifying the RRP in the experimental CROM. Several Maximum Level of Comfort (MLC) positions were found within the RRP. RESULTS: RRPs for lower limbs of men and women have been identified and can be used for virtual comfort assessment. CONCLUSIONS: This paper shows a method to evaluate in a more objective way the subjective postural comfort perception and results allow researchers to improve models for the virtual preventive comfort assessment.

Keywords: Comfort evaluation , lower limbs joints , range of motion , rest posture

The aim of this work is to define a new method that helps researchers to analyze perceptions of (dis)comfort in dynamic conditions. Recent studies pay considerable attention to body movements, mobility, and stability to measure comfort or discomfort when seated. Most of these discuss the relations between subjective comfort/discomfort and objective measurements (e.g. body pressure distribution, body movement and EMG) for short- and medium-term sitting. The present analysis took place in a classroom of the Industrial Engineering Department at the University of Salerno. The participants included 25 students (12 females and 13 males), who were observed during classroom hours. The students were invited to sit at a combo-desk and were free to perform different combinations of movements while writing and listening. These activities required that they adapt their body movements, as the combo-desk was fixed to the floor. A pressure pad was used to detect pressure at interface and center of pressure's changes, allowing for the bodies' motion data to be recorded. The aim was to identify the correct threshold to be used for movement detection and to investigate correlations between the number of movements and the perceived (dis)comfort. The study also identifies those body parts that have the greatest effect on (dis)comfort perception.

Keywords: Body movements , Center of pressure , Classroom seat , Comfort , Discomfort , Pressure map , School furniture

The most advocated schemes of comfort perception have proposed an objective method to evaluate “effects in the internal body” and “perceived effects”—the state of the art for comfort/discomfort evaluation. Postural comfort is one aspect of comfort/discomfort perception, and this current work adds to existing knowledge toward a more objectified posture evaluation for comfort. The authors have used the concept of Range of Rest Posture (RRP), as proposed by Apostolico et al. [1], useful for comfort evaluation. The study focused on the identification of RRP within the Comfort Range of Motion (CROM) for these human joints in the lower limbs: hip, knee, and ankle. The proposed method is based on extensive experimental work involving 114 healthy individuals (59 males and 55 females) ranging from 20 to 40 years old. The age range was narrowed to avoid an age-clustering of results due to inhomogeneity of the statistical sample. The experimental data were processed using statistical methods for identifying the RRP in the experimental CROM. Several Maximum Level of Comfort (MLC) positions were found within the RRP. These positions were among the most important information in the comfort evaluation analyses.

This work is focused on the analysis of the fall of a human being from a given height. With reference to forensic disputes, the final subject position is often the only evidence and foreseeing the body trajectory and the respective driving force may not be trivial. This article illustrates how multibody models can be used for this aim. A multibody model of a human subject has been built, given his stature and his known mass. This model was made of 15 segments, whose inertial properties, joint centres and volumes were deduced from anthropometric databases. This model was validated against experimental tests performed on a Hybrid III dummy: it was able to reproduce the peak impact head force with an error lower than about 10%. Some examples are produced to illustrate the usefulness of this validated model as a tool for the analysis of falls, and how it can be easily parametrized to make multiple simulations with different initial conditions/environment configurations. As such it is a valuable tool for forensic analyses.

Keywords: Anthropometric data , Fall from height , Forensic biomechancis , Multibody model

The designers of two-wheeled motorcycles, in the phase of setting up a new project, have the need to carry out ergonomic evaluations on both the pilot and the passenger, from which the optimal comfort and control conditions will arise during the future use of the vehicle. Commonly, the most used method is based on the previous experience of the manufacturer and on the comparison with the choices made by the competitors. This article describes a methodology developed in collaboration with the Italian motorcycle brand Aprilia, owned by Piaggio & C., a company world leader in the sector, designed for the setup phase of new vehicles. The method provides a flexible tool, starting from the Enduro segment and for the different users' body size (expressed in percentiles). The analysis was done on five commercial Enduro motorcycles from different leading competitor manufacturers. The authors used a mixed method based on numerical and experimental data, detected on virtual models, and on report cards made by professional testers. The results have been showed and discussed.

Keywords: Anthropometric , CAE , Ergonomics , Human factors , Motorcycles

In the speed-based competition, with the use of fast vehicles, a fundamental aspect is the safety and comfort of the drivers. In each speed-based competition, the drivers are subjected to vibrations and stresses whose evaluation is fundamental in order to quantify the discomfort of them. The comfort conditions are guaranteed by a deep study of the correct size of the internal spaces, the right posture of the drivers and the right choice of the position of the elements inside the vehicles (damping elements, position of the steering wheel, position of instruments, etc.). Another important aspect is the assessment of the escape spaces in case of accident. To reach these goals, the Governing Body act with the definition and the verification of technical rules. In this work the field of interest is powerboats sport. During the powerboat race, the reached speed and the z-acceleration of the boat lead to several stresses on drivers. Two different approaches have been investigated, a traditional 2D approach and an innovative 3D approach. Results have been discussed.

Keywords: Ergonomics , Human factors , Safety design , Seat comfort