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U. Schultheis

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7 records found

Journal article (2022) - J.M.A. Bouwens, L. Fasulo, S. Hiemstra-van Mastrigt, U. Schultheis, Alessandro Naddeo, Peter Vink
The aviation industry is constantly making compromises when designing comfortable airplane cabins. Providing passengers with a pleasant acoustic environment without adding weight to the cabin structure is a field of tension that challenges cabin interior designers. The aim of this study was to investigate whether noise levels affect the comfort and physical discomfort experienced by airplane passengers, and whether control influences comfort perception. To this end, 30 participants experienced three conditions (silence, aircraft engine noise at 75 dB, and the same noise with the ability to use earplugs), and comfort and discomfort were measured using a questionnaire. It was concluded that aircraft engine noise negatively affected the airplane passengers’ comfort experiences. Having the ability to control this noisy environment with earplugs resulted in the lowest reported physical discomfort. ...
Journal article (2019) - M. Smulders, A. Naddeo, N. Cappetti, E.D. van Grondelle, U. Schultheis, P. Vink
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. ...
Journal article (2018) - Joyce Bouwens, Luisa Fasulo, Suzanne Hiemstra-van Mastrigt, U. Schultheis, Alessandro Naddeo, Peter Vink
Sitting still for extended periods of time can lead to physical discomfort and even serious health risks. Due to safety regulations, reducing passenger’ sitting time in aircrafts is not feasible. This paper presents the results of a laboratory study, in where an interactive airplane seat was compared with a current economy class seat. Participants used both seats for 3.5 h, and performed significantly more in-seat movements when using the interactive seating system. Furthermore, this interactive seat predominantly lead to significantly better comfort experiences and reduced discomfort experiences, however no significant differences have been found in self-reported localized musculoskeletal discomfort. Passengers indicated that they would prefer this interactive seat over a standard aircraft seat. ...
Journal article (2018) - Joyce Bouwens, U. Schultheis, Suzanne Hiemstra-van Mastrigt, Peter Vink
There is certainly room for economy-class travelers to make their trips more pleasant. A travel pillow might improve comfort. In this study, the comfort expectations and experience of travel pillows were examined. Comparing these 2 aspects indicated that it is not always possible to predict the comfort experience associated with a product based on a picture, and that there is a discrepancy between expected and experienced comfort. Experienced comfort is highest for travel pillows that restrict head movements in all directions in order to maintain a neutral posture. The results of this study also support earlier studies that suggested that discomfort experience can be predicted by observing the number of participants’ in-seat movements; more movements result in higher experienced discomfort ...
Conference paper (2017) - M. Smulders, Alessandro Naddeo, N. Cappetti, Elmer van Grondelle, U. Schultheis, Peter Vink
In designing a headrest it is important to define the ideal head position and neck angle. There is literature on the ideal head position, but not in the context of watching IFE in a business class aircraft seat. In this study (n=21) the neck muscle activity (EMG), expected long-term comfort and head/neck inclination were studied in a reclined position (as is possible in business class) when watching IFE in the condition of with and without head/neck support.

It appeared that there were no significant differences in EMG between both conditions. However, the posture was significantly different; without head support by a headrest the head was found to be more upright. Expected long-term comfort was rated highest in the condition with a headrest.

The fact that no difference was found in EMG indicates that humans tend to look for a head position that is neutral, in the sense of minimal (muscle) effort. Head support in a reclined position may have a positive psychological effect on the user. ...
Journal article (2016) - Nienke Nijholt, Tjits Tuinhof, U. Schultheis, J.M.A. Bouwens, Peter Vink
BACKGROUND: Passenger comfort is a key variable in user acceptance of transportation systems. The back rest of a seat is of importance part in this experience. In designing a backrest, information of the human contour is useful as the product can be formed following this contour. The question is whether there is too much variation due to variety in tasks or in human anthropometry to design a back rest. OBJECTIVE: The research question is whether anthropometric properties and the performed activity have an influence on the back contour of a person. METHODS: The head, neck and back contour of a human sitting in an aircraft seat are estimated by using a kyphometer. In total 46 subjects are measured in two different chairs, when performing two different activities. RESULTS: This research indicates that the maximum variation of the contours occur on the upper back, neck and head. These parts are more bended forward when using a laptop compared with watching IFE. By dividing the data in groups, based on buttock-top of head distance, the height at which significant differences between the groups occur was determined. For one seat 400 mm above the seat pan a significant difference was found and for the other seat this was 420 mm above the seat pan. CONCLUSIONS: Differences in back contour started to appear above 400 mm vertical distance from the seat pan, which means that the design of a seat should facilitate this variation. ...
Journal article (2016) - M. Smulders, K. Berghman, M. Koenraads, J. A. Kane, K. Krishna, T. K. Carter, U. Schultheis
BACKGROUND: The concept of comfort is one way for the growing airline market to differentiate and build customer loyalty. This work follows the idea that increasing the contact area between human and seat can have a positive effect on comfort [5, 6, 7]. OBJECTIVE: To improve comfort, reduce weight and optimise space used, a human contour shaped seat shell and cushioning was developed. METHODS: First the most common activities, the corresponding postures and seat inclination angles were defined. The imprints of these postures on a rescue mat were 3D scanned and an average human contour curve was defined. The outcome was transferred to a prototype seat that was used to test the effect on perceived comfort/discomfort and pressure distribution. RESULTS: The resulting human contour based prototype seat has comfort and discomfort scores comparable to a traditional seat. The prototype seat had a significantly lower average pressure between subjects' buttocks and the seat pan over a traditional seat. CONCLUSIONS: This study shows that it is possible to design a seat pan and backrest based on the different contours of study subjects using 3D scan technology. However, translating the 3D scans into a prototype seat also showed that this can only be seen as a first step; additionally biomechanical information and calculations are needed to create ergonomic seats. Furthermore, it is not possible to capture all different human shapes and postures and translate these into one human contour shape that fits all activities and all human sizes. ...