Human factors and ergonomics

Despite the increasing importance of human–machine interaction (HMI) in design, there are not reference models defining and describing design activities where users are directly involved in the team. Some years ago, the situated function–behaviour–structure (FBS) framework was developed to model traditional engineering design processes but these mainly focus on technological matters and users are not directly addressed. The goal of this research is to extend this framework to cover several aspects of the HMI field. To achieve this goal, an existing design aid named interaction design integrated method is exploited. The design activities based on this aid are mapped onto the situated FBS framework to highlight possible lacks or misalignment. The outcomes are used to find where and how to intervene to extend the framework. The mapping highlighted six criticalities and their analysis allowed for adding the users as a new agent in the design process, as well as for introducing new variables and design activities referred to this new actor.

Keywords: Descriptive models of design processes , Human–machine interaction , Situated function–behaviour–structure framework , User–centered design

This research aims at moving from design for disabled people to design led by disabled people. This is achieved by defining a roadmap suggesting how to involve people affected by Autism Spectrum Disorder (ASD) in design. These people could represent an added value given their uncommon reasoning mechanisms. The core of the roadmap consists of tests involving groups of ASD and neurotypical people. These tests are performed using shapes; the testers are asked for interacting with these shapes and highlighting aroused functions, meanings and emotions. The outcomes are analyzed in terms of variety, quality, frequency and originality, and elaborated in order to pursue unforeseen, innovative design solutions.

Keywords: Autism Spectrum Disorder (ASD) , Design Activities , Design by disabled people

The evaluation of the exposure to risk factors in workplaces and their subsequent redesign represent one of the practices to lessen the frequency of work-related musculoskeletal disorders. In this paper we present K2RULA, a semi-automatic RULA evaluation software based on the Microsoft Kinect v2 depth camera, aimed at detecting awkward postures in real time, but also in off-line analysis. We validated our tool with two experiments. In the first one, we compared the K2RULA grand-scores with those obtained with a reference optical motion capture system and we found a statistical perfect match according to the Landis and Koch scale (proportion agreement index = 0.97, k = 0.87). In the second experiment, we evaluated the agreement of the grand-scores returned by the proposed application with those obtained by a RULA expert rater, finding again a statistical perfect match (proportion agreement index = 0.96, k = 0.84), whereas a commercial software based on Kinect v1 sensor showed a lower agreement (proportion agreement index = 0.82, k = 0.34).

Keywords: Ergonomics , Kinect v2 , RULA

Text legibility in augmented reality with optical see-through displays can be challenging due to the interaction with the texture on the background. Literature presents several approaches to predict legibility of text superimposed over a specific image, but their validation with an AR display and with images taken from the industrial domain is scarce. In this work, we propose novel indices extracted from the background images, displayed on an LCD screen, and we compare them with those proposed in literature designing a specific user test. We collected the legibility user ratings by displaying white text over 13 industrial background images to 19 subjects using an optical see-through head-worn display. We found that most of the proposed indices have a significant correlation with user ratings. The main result of this work is that some of the novel indices proposed had a better correlation than those used before in the literature to predict legibility. Our results prove that industrial AR developers can effectively predict text legibility by simply running image analysis on the background image.

This study describes an User-Centered approach to design an User Interface (UI) to support daily activities of people with dementia. Such interface is the main hub of a home automation system able to monitor the house and reminds to the users some information when they approach the door to leave the home. In order to involve end users in UI evaluation at the end of the first stage of the design process, a specific experimental protocol, based on task analysis, structural interview, and behavioral observation, is defined. It allows to evaluate user-machine interaction considering aspects related to both adequacy of product feature and user's subjective opinion and behavior. A disposable high fidelity prototype of the UI is realized by using a touch screen tablet. Two tests, respectively dedicated to verify the adequacy of the icons and the understandability of the interface, are performed. A total of 20 subjects with different MMSE score are involved. Results show that people with low and medium dementia are able to understand and use the touch interface and provide some suggestion about how the GUI can be improved. Finally, some approaches to support the future development activities and the next usability tests are discussed.

Keywords: Assistive Technology , Dementia , Human-Computer Interaction , Usability Evaluation

During old age, perceptual and cognitive abilities naturally decline, resulting in an increased difficulty at performing complex activities, e.g., cooking. A digital cookbook, complying with design recommendations, was designed to assist older adults in meals preparation. In particular, three versions were compared in a between-subjects experiment: one based on text, one based on text and images and one integrating text and videos. The study reports on a preliminary evaluation aiming at (a) testing the feasibility of the digital cookbook as a means for assisting older users and (b) which feature was more effective. All versions were well-received. Results from behavioral observations suggest that the image-based version was more beneficial as compared to its video-based counterpart. No differences emerged between the image-based and the text-based versions. In general, the digital cookbook proved to be an effective tool. However, the inclusion of complex multimedia materials, e.g., video tutorials, can be detrimental for healthy older users.

Keywords: Ageing in place , Older adults , Touch screen interface

Touchscreen technologies have become increasingly common in personal devices, so it seems necessary to improve their accessibility and usability for the older people. In the past years, a lot of studies have been conducted to improve touch interfaces, however, most them do not consider older people with very low attitude with ICTs. Moreover, the majority of studies date back 2014, so they lack to consider the most innovative technologies available today. The present study involves a sample of older people without previous experience with ICTs with the aim of analyzing how basic features of a touchscreen interface affect their performances with typical touch-gestures. A total of 22 participants have been involved. Results partially confirm the existent literature and partially reveal new interesting findings that can be useful to improve the touch screen accessibility for older people.

Keywords: Accessibility , Human computer interaction , Older people , Touch gestures , Touchscreen interface , Usability

The topic of digital manufacturing is increasingly emerging in industry. One of the main scope of data digitalization is achieving more efficient factories. Different techniques and tools under the Industry 4.0 paradigm were already discussed in literature. These are aimed mostly at boosting company efficiency in terms of costs and environmental footprint. However, from a sustainability point of view, the social theme must be equally considered. While energy flows or costs can be already monitored in a production plant, this is not valid for data related to human effort. Monitoring systems aimed at supervising factory social sustainability were not already discussed in literature. The aim of this paper is to propose a method to acquire social related data in a production plant. The method is supported by a smart architecture within the concept of IoT factory. Such architecture permits to monitor the parameters that could influence social sustainability in a production site. After a discussion on production plants facilities and features, the parameters that need to be considered to guarantee socially sustainable manufacturing processes are identified. A set of sensors controls these data taken from different sources, including operator vital signs. Operations as well as humans are monitored. Data acquired by sensors are collected by a central server. A decision maker can interpret the data and improve the production system from a social point of view, implementing corrective actions. Data can be exploited not only for social assessments but even for other analyses on the production system. Guaranteeing social sustainability could boost the factory productivity. A case study is included in the paper: smart sensors are implemented in a production line to understand the operations efficiency in terms of social sustainability.

Keywords: digital manufacturing , smart sensors , social sustainability

Search engines play an important role in determining the success of e-commerce. Despite many efforts have been made to improve searching methods (SM) they remain mostly limited to semantic elaboration of keywords. This implies that the SM are not capable of supporting the research of products that best satisfy customers, according to their characteristics and background. To overcome this limitation, this paper introduces an approach able to define a new ontological model that formalizes the knowledge necessary to implement a search engine capable to guide the customer to search the desired product or service according to his/her characteristics and needs. To this purpose, three essential aspects have been considered: a User Ontology (UO), a Product Ontology (PO) and rules (or properties) to link the user and product ontologies. The described approach is applied, as an example, to the products class known as Smart Objects that are part of the Internet of Things (IoT) market.

Keywords: Internet of things , Ontologies connection , Product ontology , User ontology , User-centred design

Wearable computers allow users to record and access information at any time. The adoption and use of such devices is largely dependent on the users' acceptance of the technology. Previous studies investigated technology acceptance of wearables without having end-users directly trying the technology. The present paper aims at assessing the user acceptance of a wearable device to support cooking related activities, together with aspects of usability and experience of use. To this end, we developed a kitchen apron with embedded commands for navigating through the contents of a digital cookbook and asked a group of younger (N = 15, mean age 23.9 SD = 2.5) and older users (N = 15, mean age 30.3 SD = 7.6) to deploy it while preparing a recipe. Respondents' opinions were collected using questionnaires after they had accomplished the cooking task required. Overall, the kitchen apron was well received by both younger and older adults. Findings suggest that the perceived usefulness of the device and the compatibility of it with users' common activities accounted for the intention to adopt and use a wearable device in the kitchen.

Keywords: Technology acceptance , Wearable computers

In an inclusive and accessible smart environments context the implementation of the “design for all” method presents several critical issues. In fact, the universal design represents a difficult challenge for the designer because it depends on the complexity of human intentions in a particular time and place. For this reason, we propose a new approach that aims to support the design of inclusive environments by improving the user-environment interaction.

Keywords: Adaptable user interfaces , Universal design

The systematic integration of user needs in the product design is a key issue in industry, especially for small- and medium-sized enterprises (SMEs), which suffer a lack of engineering methods and resources. Moreover, most of the approaches described in the literature are not flexible enough to be tailored on the SMEs' needs, involve users only in the early design phases and are not fully accessible due to the high cost in their implementation. The present paper proposes a user-centred design methodological framework specifically focused on SMEs, which supports the designer from both design and manufacturing aspects along the engineering product design process. The framework integrates engineering methods with Web-based software tools, which enable the communication and the concurrent work of the design team, and supports direct participation of users. Beside state-of-the-art methods, the framework allows the integration of specifically tailored techniques. The framework is successfully validated through an industrial case study developed in collaboration with an Italian SME. As a result, the design of an injection-moulded housing and the related interfaces of a biomedical electronic device are achieved with a reduction of uncertainty and development time, by involving users throughout the design phases and suggesting methods and tools on the basis of the designers' know-how and SME's specific resources.

Keywords: Decision theory , Design methodology , Product design , QFD , SMEs , User-centred design

In this research activity, a new methodology for the synthesis of hand exoskeleton mechanisms has been developed and validated through real prototypes. The innovative methodology is based on a new parallel mechanism and has been tested by building a robotic assistive device for hand opening disabilities applied to real cases. The studied robotic orthosis is designed to be a low-cost, adaptable and portable hand exoskeletons to assist people with hand opening disabilities in their activities of daily livings. As regards the methodology for the synthesis of hand exoskeleton mechanism, the authors propose to use a motion capture system to acquire the real hand phalanx trajectories and the geometrical characteristics of the patient's hand, and to use optimization algorithms to properly defines the novel kinematic mechanism that better fits the finger trajectories. The preliminary testing phase of the prototype on a single patient is concluded; currently, through the collaboration with an Italian rehabilitation center, a group of patients are testing the proposed HES methodology.

Keywords: Hand exoskeleton , Hand opening disabilities , Kinematic synthesis , Portable and wearable robotics

The design of an aid for the hand function based on exoskeleton technologies for patients who have lost or injured hand skills, e.g. because of neuromuscular or aging diseases, is one of the most influential challenge in modern robotics to assure them an independent and healthy life. This research activity is focused on the design and development of a low-cost Hand Exoskeleton System (HES) for supporting patients affected by hand opening disabilities during the Activities of Daily Living (ADLs). In addition, the device, able to exert suitable forces on the hand, can be used during the rehabilitative sessions to implement specific tasks useful to restore the dexterity of the user's hand. The validating and testing phase, conducted in collaboration with the Don Carlo Gnocchi Foundation, showed satisfying results both in terms of portability and wearability which are fundamental requirements for assistance during the Activities of Daily Living (ADLs) and for rehabilitation of people with hand impairments.

This work lays the foundations of a self-collision aware teleoperation framework for compound robots. The need of an haptic enabled system which guarantees self-collision and joint limits avoidance for complex robots is the main motivation behind this paper. The objective of the proposed system is to constrain the user to teleoperate a slave robot inside its safe workspace region through the application of force cues on the master side of the bilateral teleoperation system. A series of simulated experiments have been performed on the Kuka KMRiiwa mobile robot; however, due to its generality, the framework is prone to be easily extended to other robots. The experiments have shown the applicability of the proposed approach to ordinary teleoperation systems without altering their stability properties. The benefits introduced by this framework enable the user to safely teleoperate whichever complex robotic system without worrying about self-collision and joint limitations.

Keywords: haptic rendering , joint limits , self-collision

This paper presents a structured User Centered Design (UCD) method to design and develop a highly usable smart home platform to manage the energy consumption of connected appliances. It exploits advanced Tangible Augmented Reality (TAR) technologies to virtually prototype the conceived design solutions and carry out usability testing with sample users. Usability tests are carried out both on traditional high fidelity prototypes and on an innovative Tangible Augmented Reality prototype. Experimental results prove the efficiency of the UCD approach supported by virtual prototypes, instead of traditional ones, the reliability of TAR prototypes to detect usability problems and assess user satisfaction, and its high interaction quality. Advantages obtainable by implementing the proposed structured UCD approach for web interface design, in the context of smart home, are discussed.

Keywords: Human Centered Computing , Human Computer Interaction , User Centered Design , User Interface Design , Virtual Prototyping , Virtual Reality

Manual work is a cornerstone of manufacturing, also for factories of Industry 4.0 era. Use cases of manual work regard the production of single item, customized assemblies, small batches. Several injuries can be caused or aggravated by manual handling activities at work. Moreover, the efficiency of the whole process can benefit from correct body posture, parts' visibility and accessibility. Finally, manual work is strongly human-centered and its performance is affected by the expertise, the level of knowledge, attitudes and belief of workers. In this complex context where multiple factors such as Efficiency, Work Performance, Ergonomics and Safety relate each other to achieve a satisfactory smart industry, the paper proposes an innovative Tangible Augmented Reality platform to train and assist workers during the manual handling and assembly tasks necessary to produce consumer goods with high aesthetic qualities. The proposed platform is the result of the application of a multipath methodology to link health and safety elements, typologies of injuries, ergonomics factors and relative qualitative and quantitative assessment methods and ergonomics analysis tools. The TAR platform allows the worker to consult the assembly instructions in a simple and user friendly way and to be informed by potential risk of injuries by a real-time alert. Based on video mapping techniques, the TAR system superimposes the necessary digital contents on the physical model of the product while the operator is building it.

Risk Management has become a taken-for-granted form of practice for manufacturing companies and in most cases a strategic for their success. The research goal is to define a multipath methodology that drives the analysts to find the proper ergonomics factors impacting on specific safety elements, how they relate to the workspace, the adopted tools, the overall production environment and to the workers' job, how to quantitatively and qualitatively measure these factors and which VP tools and experimental set-ups could be used to conduct simulations. A case study is used to illustrate the methodology.

Keywords: ergonomics on work efficiency and injuries' recduction , human behavior simulation , Management of risks postures , Virtual Prototyping-based tools , VP tools , work efficiency

The purpose of the research is to develop an intelligent system able to support the design and management of a Customer Experience (CX) strategy based on the emotions tracked in real time at the different touchpoints in a store. The system aim is to make the shopping experience responsive to the customers' emotional state and behaviour and to suggest successful product/service design guidelines and customer experience (CX) management strategies whose implementation may affect current and future purchases. In this particular, the present paper focuses on the description of the integrate approach developed to design the overall CX and on the emotional recognition tools to elaborate the rich-data captured by a network of optical and audio sensors distributed within the shop.

Keywords: Big Data , Collaborative CX design approach , Customer experience , Emotional recognition

Over the last years, several approaches have been defined to support Universal Design. However, a method that allows supporting universal design process in a systematic way is still lacking. Consequently, very often, products are merely designed according to design guidelines, without considering their effective context of use, while the success of products is often determined by the experience, intuition and sensitivity of designers, rather than by a real good design practice. In this context, the paper propose a systematic approach to support the conceptual design of modular and adaptive products, where for products we mean any device, tool, artefact, building, or service.

Keywords: Ability-oriented design , Adaptive systems , Human factors , Universal design , User-centered design