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.

A Critical Review of Seating Discomfort and Anthropometric Consideration for Tractors

The seats that are available in the tractors are not as sophisticated as in the cars and most of the tractor operators feels discomfort while operating the tractor. This review not only makes the tractor seat sophisticated one but also includes all other design considerations. It is necessary to design a seat by considering various factors like dimensions, cushioning, anthropometry etc. Anthropometric consideration is not a mere assumption here. In the view of anthropometry, a survey form was created to analyse various pain levels of a tractor operators. The survey was taken from different age and different experience tractor operators to obtain more relevant data for the analysis. At the end of analysis, the dimensions were varied according to the analysis and also consider the ISO and BIS recommendations. To give more comfort to the tractor operators some additional features like hand rest, air cushioning for the seat were added and these also reduce the tractor operator’s pain.

Numerical Modeling of Air-Based Bus Seat

Travel with long hours will create discomfort feeling for passenger especially express bus passenger. Long hour travel will create physiological stress on passenger. It may due to seat space limitation, noise, vibration, seat hardness as well as seat comfort. Seat comfort is a subjective feeling that related to psychological aspect of passenger. In this project, the bus passenger seat is integrated with air-based and gel-based material. In Malaysia, most of the express coaches are using polyurethane foam based cushion in the seat padding. This type of the seat padding may cause a bus passenger who sit for long journey will feel uncomfortable and fatigue. There are two main causes which lead to seating discomfort which is vibration and pressure distribution on the seat. The new design a bus passenger seat is using air-based cushion to improve the seating comfort. The air-based seat was validated by using MatLab SimuLINK software. In the model validation process, the parameters of air cell height gave effect on the pressure change rate of air cushion model. The comfortable level of the air cushion could be improved by reducing the pressure change rate and cell height.

Parameters Influenced in Car Seat Design from Ergonomic Perspectives - A Review

Seats are one of the most important components of vehicles and they are the place where professional driver spend most of their time. Since the beginning of the automotive industry, providing a comfortable, economical and safe ride to the customer, has been the prime objective of all the manufacturers regardless the brand. Present review is done in order to mainly focus on various parameters which lead to seating discomfort in cars. Human experienced seating discomfort has been discussed briefly and ergonomic approach to overcome discomfort has also been analyzed.