A Development of the Self Shape Adjustment Cushion Mechanism for Improving Sitting Comfort

The seat comfort of automobiles is one of the significant factors for determining the driver’s fatigue, emotional experience, and individual space (which captures their individuality, rather than just a means of transportation in modern society). Conventional automobile seats could not provide seating comfort suitable for all drivers, in the form of seats that fit each driver’s body type and the difficulty of meeting individual needs. This study proposes self-shape adjustable (the SSA seats) seats that improve the sitting comfort, safety, and secure the stability, by adjusting shape fit to the driver’s body type. The SSA seats transforms the seat itself, in a way that improves the distribution of contact pressure and reduces sitting fatigue, with the pneumatic system. The transformed seats provide better sitting comfort and safety than the conventional automobile seat, by providing a seat shape suitable for the body shape of all users. It was verified that the SSA seats, proposed in this paper, have a uniform and improved pressure distribution, compared to the conventional seat, in various sitting postures; the contact area between the seat and user is enlarged, and the pressure concentrated on the ischial bone is lowered. In addition, it was proven (through user evaluation) that quantitative evaluation verification was the same as qualitative evaluation results.

Development of Comfort and Safety Performance of Passenger Seats in Large City Buses

A bus seat needs to be designed ergonomically for better seating comfort. The present study is intended to develop a cost-effective ergonomic bus seat design based on seat comfort and safety demands. As part of the proposed seat design procedure, seating comfort analysis, identifying preferred design features, and developing a seat design are included. An analysis of the bus seat back and seat pan profiles was conducted. Based on the results of the comfort analysis, the authors identified the preferred design features of bus seats during the design identification process. An improved bus seat prototype was developed based on selected design features in the design development stage. Seating comfort analyses were used to compare the achieved seat with the reference seat. The seat design developed in the present study may be applicable for various types of bus public transport.

A model-based approach for the analysis of aircraft seating comfort

BACKGROUND: Aircraft seating comfort has a significant impact on passenger on-board experience. Its assessment requires the adoption of well-designed strategies for data collection as well as appropriate data analysis methods in order to obtain accurate and reliable results. OBJECTIVES: This paper focuses on the assessment of aircraft seating comfort based on subjective comfort responses collected during laboratory experiments and taking into account seat features and passenger characteristics. METHODS: The subjective comfort evaluations have been analyzed using a model-based approach to investigate the relationship between overall seating comfort and specific seat/user characteristics. RESULTS: The results show that the overall seating comfort perception is significantly influenced by the thickness of the seat pan, the backrest position (upright or reclined), the age of the passenger and the passenger perception of being comfortably supported at the lumbar region. CONCLUSIONS: The adopted model-based approach allows the analysis of subjective seating comfort data taking into account their ordinal nature as well as the dependency between evaluations provided by the same subject.

Objective and subjective evaluation of a new airplane seat with an optimally pre-shaped foam support

BACKGROUND: Aircraft seat manufacturers are making efforts to reduce seat weight while continuously increasing seating comfort. OBJECTIVES: To verify if seats with an optimally pre-shaped foam support could improve seating comfort while reducing seat weight. METHODS: The optimally pre-shaped surface was obtained from a synthesis of 95% of individually optimized compressed seat pan surfaces of a target population. Two new seats were proposed with two different cushions, one slightly softer and the other harder. Nineteen differently sized volunteers tested the two new seats and an existing seat randomly. After an assessment of initial discomfort, participants were instructed to watch a TV series for 50 minutes. A same questionnaire was used to assess both initial and longer-term discomfort. Contact forces and pressure distribution were analysed as well in-chair movements (ICM) during sitting. RESULTS: The two new seats exhibited lower shear, lower peak pressure and larger contact area on the seat pan as well lower number of ICM during the 50 minutes sitting. They also had lower initial overall discomfort, though significant differences between the seats were not found after the long sitting. CONCLUSIONS: Properly pre-shaped surface could be used as foam support to reduce the amount of foam while reducing seating discomfort.