Author: Kassim Abdulrahman Abdullah, Muhammad Uba Abdulazeez, Waleed Fekry Faris, Sheikh Jobe

Abstract: Digital human modelling (DHM) offers a way of representing the intended vehicle users and task requirements using their anthropometric dimensions and computer graphics. This helps in avoiding the need for early user trials leading to a massive time-saving. Also, this enables the early consideration of human factors issues in the vehicle design process thereby decreasing the possibility of costly and impractical adjustments at the advanced vehicle development phases. An ergonomic automotive seat suitable for the Nigerian population was designed using CATIA V5 software based on proposed seat dimensions from our previous study. This work seeks to evaluate the suitability of the proposed seat and SAE J1100 vehicle package dimensions for the Nigerian population based on their anthropometry. Six custom-built Nigerian manikins were postured as drivers and passengers in a vehicle package based on CATIA V5 Human Builder vehicle occupant accommodation and another seven manikins were positioned on the seat designed for the Nigerian population. Rapid Upper Limb Assessment (RULA) ergonomic analysis conducted on all the manikins in the vehicle package both as drivers and passengers’ showed that the SAE J1100 package dimensions are unsuitable for the Nigerian population with overall RULA scores between 3 to 6 for drivers and 4 to 5 for passengers. The choice of transmission type and an enhanced seat height were found to provide improved body and postural comfort for the Nigerian driver population with a difference of 1 to 3 in the final RULA scores. However, an improved seat height was found not to give enhanced body and postural comfort for most of the Nigerian passenger population due to the effects of other SAE J1100 package dimensions with uniform overall RULA scores of 4 and 5. Finally, the seat designed for the Nigerian population proved to fit and accommodate them comfortably with acceptable RULA scores of 2 for all the seven Nigerian manikins analyzed.

Keywords: Digital Human Modelling, Rapid Upper Limb Assessment, Vehicle Occupant Accommodation, Ergonomics