Truck drivers' postural and visual behavior An explorative study to understand expectations on current designs and future vehicles

After several decades of small incremental improvements, the development of ergonomics in truck driving environments is now facing a potential change with the introduction of autonomous driving. The knowledge on what happens to the driver’s posture and vision related behaviour with an increasing level of automated driving is still very limited. The aim of this paper is to understand truck drivers’ expectations on both current vehicles and future trucks with an expected increased level of automation, and to see how the expectations relate to previous driving posture related research. Truck drivers’ postural behaviour is determined by several contextual factors. Some are related to the actual driving task and traffic situation, and some related to the cabin layout. Individual variability also largely affects the choice of sitting posture. The field of vision is often prioritized over sitting comfort in increasingly complex driving environments and drivers tend to adapt to a more forward leaning posture to get a better overview in these situations. An increased level of automation could potentially allow drivers to get an increased freedom in choosing their preferred postures but also possibly mean a change in their working tasks, with increased possibilities of performing secondary working tasks like transport planning and handling orders. However, the interviewees in this study generally imagined increased opportunities of finding relaxing and comfortable sitting opportunities rather than a change in the working task as a result of increased automation