The Fleet Business Authority
Issue link: http://heavydutytrucking.epubxp.com/i/307131
A s well as being in short sup- ply, trucking's new recruits are also, shorter generally, and thinner, as well as less likely to want a truck to look and feel like a truck. The challenge for truck makers comes in designing truck cabs to fit an expand- ing body-size profile, while making the driving environment appealing to people who have different expectations about trucks – all without alienating the existing driver population. Jason Spence, Volvo Trucks product marketing manager and formerly market research and industry trends manager, says there have been subtle but obvious changes in drivers' weight and form in recent years. Spence says drivers are getting smaller. "There has been a down- ward shift in the prevalence of what we describe as morbid obesity to more of an over- weight status, and even further into what you could call a nor- mal body mass index," he says. "There are a number of reasons for that, but it does not appear to be because of improving health. The driver population isn't trimming down; the larger ones are being trimmed out." Volvo's analysis shows in 2008, the average driver weight was 232 pounds, but 2013 it was down to 216 pounds. Volvo uses the National Institute for Occupational Safety and Health's large-scale body-type surveys, and Spence has seen a change in the group representing the 95th percentile male to the 5th percentile female. "The range in body size has increased with the influx of smaller Latino, Eastern European, and South Asian males and generally smaller female drivers," Spence notes. This can affect design items such as door handle placement, the amount of force required to open the door and even the step placement, considering the height from the ground and the distance between the steps. To put it succinctly, truck cabs and all their amenities and service points have to comfortably accommodate body types ranging from something like a 5-foot, 2-inch, 110-pound female to a 6-foot, 5-inch, 300-pound male. Truck makers have to account for various eye positions relative to the dash behind the steering wheel, vis- ibility over and around the hood and the mirrors. Drivers have to be able to reach the inspection points on the en- gine, and, of course, have the strength to open the hood. Andy Weiblen, Peterbilt's assistant chief engineer, says the force required to open the hood on the Model 579 52 HDT • MAY 2014 www.truckinginfo.com Jim Park • Equipment Editor Driver demographics are driving changes in cab designs DTNA engineering uses a range of digital mannequins developed from a statistical analysis of measurements taken from actual truck drivers. e r g o n o m i c s _ m a y . i n d d 5 2 ergonomics_may.indd 52 4 / 2 9 / 1 4 3 : 5 1 P M 4/29/14 3:51 PM