Field research on actual driving postures and seat configurations in a coach

Objective: The objective of this study is to investigate actual driving postures and seat configurations in a coach based on field research data. Background: Vehicle cockpit should be ergonomically designed because it is closely related with safety of drivers and passengers. Especially coach takes on more passengers and is more difficult to drive than the other vehicles such as a sedan and a recreation vehicle, thus it is important to design coach cockpit ergonomically. However, few studies have focused on a coach cockpit especially driving posture and seat configurations which were basic data for cockpit design. Method: For the 34 coach drivers, we took pictures of their driving posture and overall cockpit, and measured seat height and seatback angle in their own vehicle. We measured forward-backward location of seat for the 19 drivers in the second field research. Results: Driving postures were classified into four groups based on torso angle of driver and contact/separate with seat; a contact with seat and erected posture, a contact with seat and normal posture, a contact with seat and relaxed posture, and a separate with seat and erected posture. For the forward-backward location of seat, 36.8% of drivers adjusted location of seat backward than the design criterion (150mm). For the seat height, mean of seat height was 20mm low than the design criterion (375mm), and 62.5% of drivers adjusted seat lower than the design criterion. For the seatback angle, 25.0% of drivers adjusted seatback angle backward than the design criterion (107°). Conclusion: We investigated the driving posture and seat configurations in a coach, and identified that there is considerable gab between actual seat configurations and design criteria. Especially large numbers of their settings could cause lack of rear space in the cockpit. Application: The results of this study can be used for basic data for ergonomic design of a coach cockpit.