She is about 1.5 meters tall, weighs 49 kilogrammes and, in dummies of the newest generation, has numerous sensors on various body parts with up to 150 measuring points.
For 20 years now, the so-called ‘fifth percentile female’ has been a driver, front passenger and rear passenger in Mercedes-Benz frontal crash tests – and is an equal to the traditional male dummy, the Hybrid III 50.
That means the company introduced the Hybrid III 5th Percentile Female dummy even before it was officially required by law. The dummy replicates the female anthropometry with female breasts and pelvic bones. According to underlying statistics, only five percent of American women are smaller or lighter. Today, ratings from consumer protection associations and various laws around the world include specifications for testing with fifth percentile female dummies.
Another type of dummy that Mercedes-Benz has used in crash tests for two decades is the SID-II female dummy. With an anatomy similar to that of the Hybrid III 5, it has been designed specifically for side impact tests. Unlike in the USA, however, its use is not yet required by law in Europe.
120 dummies in 21 different versions undergo up to 900 crash tests each year
For more than 50 years, Mercedes-Benz’ in-house accident research centre has been investigating accidents involving Mercedes-Benz vehicles. The aim is to understand how accidents happen and which advanced safety systems could have prevented them.
What’s more, findings from real-life accidents can be used to define requirements for crash tests. The Mercedes-Benz Technology Centre for Vehicle Safety in Sindelfingen conducts up to 900 crash tests and 1,700 sled tests every year. The tests involve 120 dummies in 21 different versions – from toddlers, children of all ages and fifth percentile female dummies to 50th percentile male dummies and large, heavy male dummies[2]. The results of the crash tests and accident research are used to help develop new safety technologies and improve existing systems.
The topic of female dummies is currently the subject of much public debate. Hanna Paul, Head of Dummy Testing at Mercedes-Benz, fact-checks six of the most common myths.
Myth 1: Cars don’t protect women as well as they do men
Hanna Paul: No, that’s not true. First of all, here are two general findings from Mercedes-Benz accident database: In the case of severe or fatal injuries, there are no discernible relevant disparities between the sexes. Only in the case of minor injuries there are certain disparities in individual cases.
Women are more susceptible to injury in some regions of the body (legs/feet and whiplash in a rear impact), while men may be more severely affected in others (head, chest). In addition, analysis carried out by our accident research team has revealed that there are no anomalies with regard to women or men in Mercedes-Benz vehicles. This shows that the safety design of Mercedes-Benz vehicles is effective in real-life accidents. This underscores our ambition of ‘real-life safety’.
Myth 2: There are statistics showing that women are less protected
Hanna Paul: Again, a resounding no. The accident figures cited in these statistics often date back to the 1980s. A great deal has happened since then in terms of passive vehicle safety. Passenger cells, even in small vehicles, have become much more stable. At the same time, modern restraint systems are now used in all vehicle classes. Belt force limiters, for example, which limit the pressure on the chest, adapt to the requirements of the occupants with a defined force curve.
However, another aspect from these often cited studies that do still apply today. Namely that in term of global statistics, women often drive older, smaller cars. This is confirmed by a study carried out by the American insurance organization Insurance Institute for Highway Safety (IIHS). But, as I already mentioned, the safety level has improved significantly in all vehicle segments, including in small cars. This led the US National Highway Traffic Safety Administration (NHTSA) to determine that the disparities in fatality rates between men and women fell significantly starting with model year 2000 vehicles.
Myth 3: Male dummies are predominantly used in crash tests
Hanna Paul: Not at Mercedes-Benz. We have been using female frontal impact dummies and female side impact dummies in our crash tests for more than 20 years. But dummies are not human dolls. They are instruments that measure physical forces and trajectories. Their weight and size are derived from real-life human data. Female dummies correspond to, are scaled to, the female anatomy. However – and this is decisive – the forces acting on dummies during crash tests are converted into injury risks. These risks are calculated based on injury data for both men and women. The common limits for female dummies are lower than for male dummies for the same injury risk. This means that the dummies do a good job of representing injury risks for the unique anatomical characteristics of men and women. The size and weight of the types of dummies used at Mercedes-Benz are gender-specific.
The fifth percentile dummy[3] has female anatomy, but in terms of injury risk, it represents small people in general – regardless of whether they are men or women. In other words, injury risks are human, not male or female. The same applies to the other dummies as well: The 50th percentile male[4] mimics the male anatomy, but it also represents the injury risks that an average woman faces. The NHTSA is currently investigating the extent to which injury risks vary by gender. The first published results confirm our findings that gender is not the most important factor influencing injury frequency. The dummies we use today are therefore effective measuring tools for developing safety systems.
Myth 4: Crash test dummies are not diverse enough
Hanna Paul: In recent years, the number of dummy types has increased significantly, partly due to the many different types of collision that are being tested. Mercedes-Benz has a total of over 120 dummies. They come in various sizes and weights – from babies weighing only 3.5 kilos and children and teenagers of various ages to fifth percentile females and heavy dummies. There are also different types for frontal, rear and side impacts. Which dummies are used in each type of crash test is defined in the test specifications set out in laws, ratings and specific Mercedes-Benz load cases. Dummies are regulated in detail to ensure worldwide comparability. Even their clothing is regulated. Dummy technology is currently undergoing a generational change. The advanced THOR dummy is replacing the Hybrid III dummy introduced in 1986. THOR dummies are more biofidelic, i.e. they more accurately depict the human body, and offer extended measurement options. According to our internal research, a further expansion of dummy types would not bring any significant improvement in safety.
Myth 5: Pregnant women are less protected
Hanna Paul: A comparison of systems in a recent study by ADAC (Allgemeiner Deutscher Automobil-Club, transl. ‘General German Automobile Club’) shows that normal seat belts protect both expectant mothers and their unborn children well in the event of an accident. According to accident research by ADAC, pregnant women are no more at risk than other drivers. When used properly, normal three-point seat belts protect both pregnant women and their unborn children in the event of an accident.
Myth 6: Simulations will soon replace physical crash testing
Hanna Paul: We don’t see that happening. It is true that calculating kinematics and deformation can significantly reduce the number of whole vehicle tests and speed up development at the same time. However, there are several reasons why there is no way around vehicle crash testing: On the one hand, crash tests are necessary to validate simulations, which are based on many assumptions. On the other hand, they are required by law or ratings. In whole vehicle tests, sensors can be used to get the best picture of how a crash develops and the dummies behave during it.
Occupant simulations merely calculate how a dummy would behave in a vehicle. Mercedes-Benz is also working on so-called human body models (HBMs), which are designed to represent human anatomy – bones, muscles and organs – in even greater detail. Compared to dummies, using HBMs in crash tests allows researchers to assess the actual type of injury that a particular part of the body is likely to suffer, rather than simply calculating the probability of injury severity. We use HBMs, among other uses, to evaluate our innovative restraint systems such as PRE-SAFE® Impulse Side.
©Copyright MOTORING WORLD INTERNATIONAL. All rights reserved. Materials, photographs, illustrations and other digital content on this website, may not be reproduced, published, broadcast, rewritten or redistributed in whole or in part without prior written permission from Motoring World International
Contact: [email protected]
