Why Crash Test Dummies Are Getting Heavier (and Older)

These safety devices need to reflect an aging and heavier population

Photo courtesy of Humanetics

In the world of automotive safety, a lot rides on what a bunch of dummies can tell us.  While that may seem counterintuitive, the individuals in question are Anthropomorphic Test Devices or ATDs.  Now - just like the rest of society - ATDs are getting obese, and older, in both form and function.

A dummy in name only:  Commonly known as "crash test dummies", these highly-sophisticated body doubles are loaded with sensors to see how human drivers and passengers will be affected during a car accident.

First invented in the late 1940s to test aircraft ejection seats, ATDs have evolved to measure impact in an automobile collision, the effectiveness of air bags and restraint systems, and to examine the full effect of acceleration and rapid deceleration on various parts of the body.

Once just an approximation of a typical American adult male, different versions now represent drivers and passengers of both genders, as well as newborn and childlike models.  Even pedestrian versions have been developed to investigate how the front-end design of a vehicle can be modified to reduce injuries during a collision.

Despite the advances in ATD design, crucial redevelopment is still needed to reflect our heavier and aging driver population, according to Chris O'Connor, President and CEO of Humanetics.  Based in Plymouth, Michigan, Humanetics is a global leader in the production of crash test dummies.

"What's existed till now was based on old data," O'Connor tells me.

 "That human body sizing research relied on measurements from anthropometry studies done in the 1970s and 80s, saying 'a standard adult has this weight and dimensions'. But in that year the obesity rate was only 15%, with an average body mass index (BMI) under 25. Now, 40% of the population has a BMI over 30.

The average driver today is not a slender person from that 1980s data."

What difference does it make if a driver or passenger is obese?  Size, weight and proportion are all key measurements when it comes to assessing injury risk during an collision, says O'Connor.  He cites research conducted at the University of California, Berkeley and the National Highway Traffic Safety Administration (NHTSA) showing that an obese driver or passenger is 78% more likely to die in a crash.

"If 40% of our population is obese," he warns, "that means they have up to an 80% greater risk of dying in a collision. Older drivers also have a higher rate of injury, from the age of 60, to 70 to 80 years.  We want to improve the odds for obese and elderly drivers."

Why older and obese adults are at higher risk for injury and death:  When we gain weight, that weight is not distributed evenly from head to toe.  Though we're only slightly taller than we were in 1980, we're an average of 25 pounds heavier. 

That extra weight generally gathers in our midsections, notes O'Connor.

 Restraint systems all rely on a narrow centre: the seat belt buckles at your pelvis, you sit against the back of the seat.  Heavier adults tend to sit forward and put the seatbelt either above or below extra belly fat. As a result, the seat belt and airbags are less effective.

Likewise for older drivers, who tend to suffer more internal organ injury than younger people do in vehicle collisions.  According to O'Connor, that organ injury is more likely to result in death.

"An older driver is a higher-risk vehicle occupant," he notes.

As a result of these safety concerns, Humanetics has designed an obese crash test dummy, and has an elderly ATD in the works.  Tested at the University of Virginia against similar-sized human cadavers, the dummies will undergo extensive study to ensure they act like the human bodies they're meant to emulate in a crash scenario.

"We need to adjust the test equipment to our new reality," O'Connor says.  "With the rate of elderly drivers and passengers going up dramatically, and our obese population, we still have a lot of work to do."

Read more about obesity and aging:


Chris O'Connor, President and CEO of Humanetics Innovative Solutions. Interview conducted December 9, 2014.


Fryar CD, Gu Q, Ogden CL. "Anthropometric Reference Data for Children and Adults: United States, 2007–2010." National Center for Health Statistics. Vital Health Stat 11(252). 2012.

Ogden CL, Fryar CD, Carroll MD, Flegal KM. "Mean Body Weight, Height, and Body Mass Index, United States 1960–2002. "Advance Data From Vital and Health Statistics; no 347. Hyattsville, Maryland: National Center for Health Statistics. 2004.

Rice, Thomas M and Zhu, Motao. "Driver Obesity and the Risk of Fatal Injury During Traffic Collisions." Emerg Med J ISSN 1472-0205, 01/2014, Volume 31, Issue 1, pp. 9 - 12.

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