Anthropomorphic Test Devices (ATDs) – otherwise known as crash test dummies – are getting older and heavier to help vehicle designers cater for ageing and increasingly overweight drivers and passengers.
In the industrialized world baby boomers are now 53 – 71 years old. They are still driving, and are expected to lead active lifestyles into their 80’s and 90’s. Drivers and passengers are also getting heavier, and not only in the West. Vehicle ownership is growing rapidly in emerging economies, where lifestyles and diets are changing. According to the World Health Organization, some 13% of the world's adult population (11% of men and 15% of women) were classified as “obese” in 2014. In addition, 39% of adults aged 18 years and over (38% of men and 40% of women) were overweight. The worldwide prevalence of obesity has more than doubled between 1980 and 2014.
In addition to these changes in the physical profiles of drivers and passengers, designers and developers of ATDs have to accommodate the complexity and variability of crash testing procedures around the world, as well as shorter vehicle product life cycles. In response, Humanetics, the global leader in the design and manufacturer of ATDs and related test equipment has been continuously developing new products to best reflect those changes while incorporating the latest technologies. Furthermore, Humanetics has developed a large suite of highly detailed and validated finite element crash dummy models in most commonly used crash codes: LSDYNA, PAM-CRASH, RADIOSS and ABAQUS to complement its physical product testing.
Humanetics also designs engineering solutions for the medical, oil & gas, agricultural, aerospace and industrial markets that cater to specific customer needs; including the design and manufacture of all applicable load cells in the crash safety area.
The company’s latest ATD developments include a Test device for Human Occupant Restraint (THOR), which is an advanced frontal impact 50th percentile adult male (THOR-50M). It incorporates enhanced biofidelic features and significantly expanded instrumentation compared to the standard Hybrid III 50th percentile adult male ATD. A THOR version representing the 5th percentile adult female (THOR-05F) is under development.
According to Humanetics, the THOR development program has been actively supported since 1985 by the National Highway Traffic Safety Administration (NHTSA) of the US Department of Transportation, as well as the European Community. In 1995, an earlier version of the THOR prototype incorporated the design elements of TAD-50M (Trauma Assessment Device – 50 Percentile Adult Male Dummy) to assess the whole-body trauma in a variety of occupant restraint environments. “The primary design objectives were: improved biofidelity and dynamic response, incorporation of specific instrumentation relevant to injury assessment, repeatability of performance, improved durability such as overload protection and user friendliness,” says the company.
The THOR ATD has been further developed and evaluated though worldwide testing. The European research community funded projects like THORAX (Thoracic injury assessment for
improved vehicle safety) has contributed to the development with Humanetics, adding an advanced shoulder with human-like range of motion. Extensive evaluations in Japan and other regions provided further input resulting in a robust tool ready for regulatory and consumer rating procedures.
While developments over the past decades resulted in advanced dummies like THOR and WorldSID for frontal and side impact applications, the focus for future developments will be on more vulnerable occupants like the overweight and overweight elderly. Overweight drivers are up to 78% more likely to die in a car crash than normal-weight drivers, according to a study from UC Berkeley’s Safe Transportation and Research Education Center (SafeTREC). Additionally, elderly occupants are statistically more likely than younger occupants to sustain serious injuries or die in low-impact crashes than younger occupants. At crash speeds of only 31 mph, a 50-year-old female has a 10% risk of serious injury in a frontal crash. With an 80-year-old female the risk is 40%.
Automotive Industries (AI) asked Christopher J. O' Connor, President and CEO of Humanetics, to share some background around the development of the company’s new THOR-M test device
O’Connor: Since road fatality reduction has largely flatlined in the industrialized world, new methods of evaluating automotive safety have become increasingly necessary. The THOR-50M is the most complex and advanced ATD ever produced for use in frontal impacts. It is designed to be more sensitive and gather more data than any of its predecessors. Automotive safety was introduced to the modern era by the Hybrid III beginning 40 years ago, but we’ve come as far as we can with the technology offered from the 1970s. THOR incorporates new and more responsive methods of data gathering, increased biofidelity, and a more targeted approach to improving safety design.
In 2016, following extensive evaluations, Euro NCAP joined NHTSA when it confirmed its intention to utilize the THOR dummy for future frontal impact tests. Updated frontal impact test procedures are being developed for implementation by 2020. These procedures will not only address restraint systems improvements, but also target improved vehicle compatibility AI: What new products and technology can we expect from Humanetics in 2017?
O’Connor: Humanetics is working with 3D printing technologies to research and develop new methods of production and produce products that have more precise response characteristics over traditional manufacturing methods. An example is a test dummy of the future with a biofidelic spinal column made of 3D printed metal or plastic vertebrae interwoven with butyl-like rubber. It can be precisely tweaked to give the exact response required within a system of flesh and organs, which also can be produced on a 3D printer.
AI: Tell us about the role Humanetics is playing in the European SENIORS (Safety ENhancing Innovations for Older Road userS) program.
O’Connor: In an ageing society, the SENIORS project aims to improve the safe mobility of the elderly and overweight persons. Various studies and projects considered the elderly road user safety including all the means of transport. Most of these focused on the loss of driving ability and the mobility issues elderly can encounter. SENIORS is unique in that it is aimed to provide safety solutions in the case of an accident occurring. In this approach, the role of Humanetics is to design and provide ATDs that represent elderly car occupants and external road users. More specifically the dummy specifications and related requirements are set in close interaction with partners based on field data and biomechanics studies. Once developed the tools will be handed over to project partners for actual testing and procedure development.
AI: Which of your ATD technologies has come into play in the SENIORS project?
O’Connor: A mix of existing and new technologies is used to contribute to the SENIORS goals. For short term implementation of the project outcome usage of existing ATDs like THOR-M or minor modifications to impactors like the Flex-PLI (Flexible Pedestrian Legform Impactor) are preferred. As an example: extensive biomechanics research into injury risk curves representing younger and older car occupants using the THOR-50M is ongoing by SENIORS partners. These risk curves represent a measure for the likelihood of an injury level arising from an impact as function of recorded signals in the ATD. Given biomechanical differences between younger and older persons, this “measurement scale” can differ and should be considered in any assessment of safety systems that provides protection to younger as well as older car occupants. The advantage of this approach is that existing ATDs like THOR-M can be used.
In the longer term, new technologies like the Elderly dummy will be investigated. This ATD is being developed by Humanetics in cooperation with medical and statistical data from industry partners which include the University of Michigan’s International Center for Automotive Medicine (ICAM). Detailed 3D representation of anatomical features and organs are being created using advanced production technologies like printing of complex rubber structures.
In order to understand injury risks within the fragile elderly population, it is necessary to include more measurement capability of the internal organs. Humanetics has simulated human organs using 3D printing technology by creating unique “foam” structures that are segmented and vary in density and response characteristics. Regional stiffness can be programmed into the organs by adjusting the printed attributes at any location. This various “programming” within the sections of the human torso is useful in pinpointing injury thresholds on the body where safety belts may contact and restrain occupants during crash situations.
AI: How has SENIORS changed the way automobile manufacturers and civic authorities deal with protection on the roads for the elderly?
O’Connor: As with all research in field of automotive safety, implementation will take some time. With projects like SENIORS, the topic is put on the agenda of all involved in car safety to have the opportunity to improve vehicles and occupant restraints with advanced safety testing tools like the Elderly and Obese dummy. Given the current interest in the THOR-50M dummy by Euro NCAP, the first applications is expected using the risk curves for the THOR-50M. Further down the horizon are the Flex-PLI legform impactor to which an upper body mass is being added in SENIORS as well as the Elderly dummy.
AI: What can you tell us about internal organ sensors you have developed?
O’Connor: Over the years, ATDs have been developed to predict possible abdominal injuries using symmetrical designs with deflection measurements. Humanetics’ new advanced related design efforts include two of the major organs in the abdominal region, the liver and spleen. This design permits the dummy to have a biofidelic local stiffness rather than a compromised overall stiffness. Liver and spleen injuries can result from pressure increase in the organ or rib fracture around the organs. This new v“According to U.S. Department of Transportation, figures in 2015 there were more than 40 million licensed drivers aged 65 and older in the United States. This represents 18,4% - or nearly one in every five drivers on the American roads.” design will have both pressure and rib deflections. It helps vehicle designers in three ways: better regional biofidelic stiffness; pressure and deflection measurements in the liver and spleen areas; and more measurements in the abdominal cavity.
AI: What are the statistics of injuries on the road for the elderly?
O’Connor: According to U.S. Department of Transportation, figures, in 2015 there were more than 40 million licensed drivers aged 65 and older in the United States. This represents 18,4% - or nearly one in every five drivers on the American roads. In 2014, more than 5,700 older adults were killed and more than 236,000 were treated in emergency departments for motor vehicle crash injuries. This amounts to 16 older adults killed and 648 injured in crashes on average every day.
AI: Do you see a similar project such as SENIORS evolving in North America?
O’Connor: Traffic safety for older road users is definitely on the agenda of NHTSA and other U.S. based organizations. However, it would seem that the only current work being done is the initiative by Humanetics in conjunction with the University of Michigan’s International Center for Automotive Medicine (ICAM) to develop tools to represent overweight and elderly car occupants. The ICAM effort is unique in that a complete ATD
Com hardware dummy, FEA dummy model, as well as Human Body Model are being developed to provide a full suite of tools for the development of adequate countermeasures to protect elderly in vehicle crashes. This has drawn the attention and interest of various OEMs willing to contribute to the developments and evaluations of the tools.
AI: How is Humanetics evolving its ATDs to keep up with autonomous vehicles, connected cars?
O’Connor: Intelligent vehicle systems like autonomous driving, connected cars as well as those systems directly related to crash avoidance like Automatic Emergency Braking are expected to change the frequency and type of accidents occurring on the roads. However, despite all advances anticipated within the next few years, accidents will continue to occur and crash testing and dummies will remain in service to improve safety. Research and development projects like SENIORS and ICAM will remain important in the future to monitor changes in the safety landscape and generate tools to reflect these changes. Another important aspect here is the focus on reduction of less serious injuries, this will require dummies with higher sensitivity in a different loading range. Biomechanical research, as well as new production technologies like 3D printing of complex rubber structures, will enable such developments