Abstract
Keywords Pressure Distribution, Vibration, Comfort, Benchmarking, Car Seat.
Abstract - Automobile seat diversity, available in the market, is nowadays very wide. Each brand introduces distinct seats, which according to the car model or segment, present assorted features and more or less accessories. Will it be that the search for comfort is present as main requirement in the design of each seat, independently of the automobile segment? Due to the fact that people are placing higher demands on their vehicles performance, seat comfort importance is increasing in the automotive industry every day. The development of more comfortable car seats is a time consuming and a very expensive process. In order to optimize this process, previous mistakes should be avoided and new ones prevented.
This work presents the results of a seat comfort study developed by the Ergonomics Laboratory of the Human Kinetics Faculty of the Technical University of Lisbon. The issue was addressed through benchmarking of automotive seats, based on analyses of two objective parameters of automobile seats usage: the pressure distribution resulting from the interface between the user and the cushioned surfaces and the vibrations transmitted to the body. For this effect, a comparative study among eight vehicle models, ranging from small cars, to sedans, vans and sport utility vehicles was carried out.
All vehicles were analysed in actual driving conditions with a single driver. Data collection was made along three different kinds of road surface, at different speeds: motorway - 120 km/h, brick paved - 60 km/h and asphalt paved with five speed breakers - 40 km/h.
The results show a positive relation between the vehicles cost and the obtain comfort level for the analysed parameters. There are however some surprises in some vehicles. We verified that car suspension plays an important role in both vibration transmission and pressure distribution. Seat cushion material and technology also had an important contribution towards the quality of pressure distribution and vibration transmission. This methodology has proven to be an essential process in evaluating car seats comfort. The results brought up important recommendations for car seat design, namely improvement of postural support and vibration attenuation.