Simulation is the key to improving representation in automotive safety testing and beyond.
Despite rigorous vehicle safety testing, current evaluations fail to adequately protect women in the case of an accident. In 2021, a study published by the Insurance Institute of Highway Safety found that women have a mortality rate 20 to 28 percent higher than men during road accidents. Women are also 37 to 73 percent more likely than men to be seriously injured in a car accident after adjusting for speed and other factors. The difference, at least in part, is due to a lack of consideration of female body types and anatomy during vehicle safety testing.
Although some car companies intentionally use multiple dummies in their vehicle safety testing, crash tests that use the standard male-sized dummy are typically the only evaluation necessary to meet many regulations. Thankfully, simulations using detailed human body models can make a more equitable testing environment possible.
“The role of digitization in ensuring highway safety cannot be overstated,” said Florence Barré Women@ESI general delegate and chief of staff to Cristel de Rouvray, CEO of ESI Group. “By incorporating diverse morphologies in simulations, virtual prototyping can better protect the entire population. Although the automotive industry has widely adopted virtual prototyping, the use of virtual human models that account for a wide range of morphologies remains optional. Therefore, legislators must take an active role in encouraging the systematic adoption of these practices to ensure optimal safety for all users, regardless of their gender or body shape.”
Clearly, all car crashes—and their victims—are not the same. Here is how governments and companies can use simulation to strive for better safety and representation.
A Lack of Female Representation in Automotive Safety
According to a 2021 Statista report, women make up just over half of all drivers in the United States. However, crash testing has traditionally relied on physical prototypes based on male height and build. The original crash test dummy, Sierra Sam, was designed to test ejector seats for aerospace purposes. Since most pilots at the time were men, the dummy was made to represent a male body.
Consumer reports notes that since the 1970s, testing has adapted to utilize a “stand-in” for a female dummy. Unfortunately, it was just a scaled-down version of the male dummy. How small? It’s consistent with the size of an average 12-year-old girl—or the smallest 5 percent of the female population. By testing this dummy in conjunction with the 95th percentile male dummy, it was believed that the testing would be rigorous enough to protect most of the population.
But height and weight are not the only factors to consider when evaluating potential injury in a car crash scenario. Gender, age and certain health conditions can impact muscle and bone strength, a person’s center of gravity and their positioning in the car. It’s these differences that likely contribute to the poorer outcomes for women in a car crash setting.
For example, consider a seat belt. Although a young boy and an adult woman could be similar in height and weight, the strength of an adult woman’s pelvis differs drastically from a developing child. The positioning of the pelvis can also be dramatically shifted in a pregnant woman or those with limb differences. All these factors differ significantly from the conventional crash test dummy, but would likely impact how the seat belt protects—or even injures someone—during a collision.
According to the World Economic Forum, the first female crash test dummy was only introduced in 2022—created by Swedish engineer Astrid Linder. The dummy was designed to intentionally model female anatomy, as opposed to being a scaled-down version of a man. These key differences allow vehicle safety testing to better evaluate seat belts, seat positioning and other core design elements in relation to a realistic female figure.
Simulating the Human Body Model
To further improve the representation of diverse bodies in crash testing, predictive physics modeling and simulation company ESI Group offers digital human body models. These models can be used in crash simulations as part of safety evaluations. In theory, they can be used to simulate any gender, size, age, weight or condition to better evaluate vehicle safety. This allows for greater flexibility in the testing process and can help companies continuously evaluate the safety of their vehicle. ESI has led in this area for years, having performed a virtual crash test on the Volkswagen Polo in 1985.
To develop a human body model accurate enough for safety testing, ESI Group informs engineering.com that it is working on top of existing software models, including Toyota’s Total Human Model for Safety (THUMS) and the Global Human Body Models Consortium (GHBMC). Although THUMS is free and open-source, the GHBMC models are only available for purchase. With these existing models, ESI is working to make models that are as useable and accurate as possible for automotive companies. Several critical challenges emerge from this work, including ensuring the model is accurate, continuous and able to be realistically positioned within a simulated vehicle.
At ESI, the goal is to create human body models that can genuinely simulate every aspect of the human experience, both internal and external. So, instead of just considering the positioning of the human body during a collision, ESI wants the model to be able to consider organ placement, bone density and other factors that can affect passenger health in a crash scenario.
Unlike traditional, physical dummies, the benefit of the simulation really comes down to its ability to be rapidly modified and deployed. Age, gender, height, weight, limb differences and more can all be changed in the human body model. Then, during post-processing, engineers can more accurately evaluate internal and external damage as a result of the crash. With simulation, the vehicle itself could also be modified to see what changes might prevent or exacerbate these injuries in diverse bodies.
So, how are these intricate models made? Primarily with detailed photography to develop the software-based simulation. Then, engineers can integrate medical imaging such as MRIs and X-rays to facilitate the modeling of the internal organs and anatomy.
The next big step is regulatory approval for simulations utilizing human body models. It will be crucial for simulated testing to count towards the safety regulations required for today’s vehicles. In this case, the benefit of the human body model over physical testing is the ability to model various car models and a diverse group of people—without endangering people or property. At the end of the day, the goal remains to protect the health and safety of all car passengers, not just those considered average.
