What are the new trends in research for comfort evaluation and the objective and predictive techniques for quantifying and qualifying comfort perception by humans? This paper has attempted to answer this question in a wide literature review, whereby it is possible to highlight many partial aspects that have been studied successfully. Just a few researchers [1–3] have studied the problem of comfort perception and evaluation under a wider point of view. Nevertheless, some aspects seem not to have yet been taken into account. In a previous paper, the authors extended the Vink–Hallbeck model to build a comfort perception/evaluation matrix in which four kinds of comfort related to different humans’ perception were studied and linked to the whole environment's characteristics. In the resultant perception-scheme and in the proposed “fusion rule” (for different kinds of perceived comfort/discomfort), one aspect that played a fundamental role in the final comfort/discomfort perception/evaluation was expectation. Expectation due to preconceived data (acquired or formed in the users’ minds) and the influence of the working environment, can act in terms of additive or subtractive factor in the comfort experience by altering the final comfort/discomfort perception and changing the subjective comfort/discomfort evaluation. This paper presents the results of expectation influence analysis on comfort evaluation. Using the placebo effect, authors conducted a wide experimental test with a wide sample of users, asking them to use and evaluate two identical mattresses that were dressed and described as two different products (the first one as a very cheap mattress and the second one as a high-level and expensive mattress). Differences between subjective evaluations have been statistically processed and correlated to anthropometric parameters to individuate and understand the role of expectatio

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In HMI design, several parameters have to be correctly evaluated in order to guarantee a good level of safety and well-being of users (humans) and to avoid health problems like muscular-skeletal diseases. ISO Standards give us a good reference on Ergonomics and Comfort: ISO 11228 regulation deals with several parameters for evaluating Postural Ergonomics in manual loads’ push/pull, in manual loads’ lifting and carrying and in repetitive actions. Those parameters can be synthesized in a “Postural Load Index” that represents the Ergonomics level of examined posture. Nothing has be done, by ISO, in order to give a method/criterion for evaluating comfort performances of products and workplaces. More than 100.000 scientific papers dealing with comfort and discomfort can be easily found in main scientific databases and most of these speak about relationship between environmental factors (like temperature, humidity, applied forces etc.) and perceived comfort/discomfort. Several papers follow the assumption that there is a relationship between self-reported discomfort and musculoskeletal injuries and that those injuries affect the perceived comfort; however, the theories relating comfort to products/processes and products/processes’ design characteristics are rather underdeveloped. One of the most recent and interesting paper about comfort perception and its evaluation is the Vink-Hallbeck (2012) one in which the Moes’ comfort perception model (2005) has been developed and improved. In our paper, a simplified model of comfort perception, that seems to work well with the Vink-Hallbeck one, has been proposed and takes into account four aspects that strongly affect the global comfort perception: (B) – User Biomechanics/Posture, (P) - Physiologic factor, (E) – Environment contribute, (C) – Cognitive factor. Each of these aspects can be split in sub-aspects that have to be taken into account in order to be evaluated and correlated to subjective comfort perception. This paper want to explain all those sub-aspects, analyze the state of the art about their evaluation and propose an easy-to-use framework for weighing and evaluating contributes coming from cognitive, postural and physiologic comfort perceptions (no environment’s factors have been studied) to the global comfort perception.

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Main purpose of this work is to show how easy and economics an ergonomic/comfort based approach, in re-design a manual assembly workplace, can be; authors, using a new comfort/ergonomic evaluation criterion, analyzed a workstation and identified the critical issues under ergonomic/comfort point of view and finally gave several guidelines to re-design the workplace, implementing minor modification, and improve work-safety, work-quality and productivity. The postural analysis was performed by non-invasive and especially inexpensive methods, based on cameras and video-recorder use and by photogrammetric analysis; DELMIA® DHM software has been used to perform all simulations; comfort analysis was performed by the software developed by researchers of Departments of Industrial Engineering of Salerno: CaMAN®. The test case is an automatic assembly machine that has been modeled and used for virtual postural analysis. Main results of this work can be found in a very good numerical/experimental correlation between acquired/simulated postures and real ones, and on the powerful use of an objective comfort evaluation method, based on biomechanics and posture analysis, for giving to designers the guidelines to re-design a workplace and a work-cycle. This kind of approach seemed to be very powerful in re-designing the work-place and in re-scheduling the work time-sheet because it allowed to improve an ergonomic corrective action with minor costs for company. Obtained results demonstrated the validity of re-design hypotheses through the increase of all comfort indexes and the improvement of workstation/operator productivity.