Virtual models of humans are being used to improve auto designs and test auto safety features.

By Salvatore Salamone

The combination of ever-more complex computer-aided engineering (CAE) simulations, new high-performance computing (HPC) clusters, and significantly more sophisticated digital computer models of driver and passenger dummies (so-called virtual crash test dummies) may enable automakers to produce safer cars.

While CAE has been commonly used for years to speed automotive design work, combining it with digital dummies is still in the development stages and not yet a substitute for mandated safety tests that autos must undergo. Still, some automakers are already using this new technology approach as another tool to help them incorporate safer elements into their cars.

So why the growing interest in virtual dummies now? “These simulations are getting realistic,” said Srini Chari, a managing partner at the HPC analysis and consulting firm Cabot Partners Group.

Chari and others note there are a number of factors that have made these tests more practical and valuable.

First, there is the growing availability of high-performance computing power. Many organizations have turned to clusters of computers, where the processing power of each unit has gone up (and prices have come down). And newer systems based on multi-core processors offer even more computing punch.

CAE applications continue to grow in sophistication, as well. Going hand-in-hand with the increase in computing power, CAE models can be more granular, allowing engineers to conduct their investigations at finer resolution. The models are also larger, thus enabling a more realistic re-creation of a vehicle and the related systems.

Additionally, the increased processing power lets designers and safety engineers run the simulations using smaller time steps and more complex physics. This provides a way to examine a sequence of events in a crash. This, in turn, can reveal a wealth of information and provide insights crucial for improved product design.

Accommodating Variety

What’s appealing about virtual dummies is that modifications can be made by changing computer code. Additionally, tests with virtual dummies can be varied easily to examine the results for a variety of different body positions, body types, velocities and impacts.

Past efforts with virtual dummies include work by Volvo that combined data from ultrasound images with a virtual dummy to simulate a pregnant woman.

Toyota, too, has developed a virtual human body model called Total HUman Model for Safety (THUMS). According to Toyota, THUMS reproduces not only the skeletal structure of a person, but also the internal organs and muscles, making it possible to understand the effects of accidents on bone structure, skin, joints, and ligaments. Toyota is using THUMS to further its research and enhance passive safety in cars.

In many ways, the adoption of virtual dummies is just a continuation of traditional auto industry practices involving physical crash test dummies, which are used to test driver and passenger safety in head-on and side-impact crashes and to evaluate the benefits of seat belts, air bags, and hardened roofs.

The mechanical dummies are not getting their pink slips, but there are a number of factors driving up the interest level for virtual dummies.

First, there is the cost and time savings. Performing a physical crash with mechanical dummies requires lots of planning, and it destroys an automobile. Virtual tests can be run repeatedly – the only limitation is the availability of computer processing power.

Second, there is increased awareness of the limitations of standard mechanical dummies. For instance, there is growing interest in having dummies with a wider range of body sizes and weights. (This interest is due, in part, to the fact that Americans, on average, are getting heavier.)

Third, there is an increased desire to get more detailed information from the dummies. For instance, last December, Ford Motor Company announced it was working with a number of children’s hospitals and other organizations to develop an abdominal insert for pediatric crash dummies (the mechanical kind), and thus address a persistent shortcoming.

“We really didn't have the technology before to accurately measure abdominal response,” said Steve Rouhana, a senior technical leader with Ford's Passive Safety Research and Advanced Engineering Department, of crash dummy testing. As a result, the major focus in most crash testing had always been on head and chest injuries. But the collaboration between Ford and the other organizations aims to make pediatric crash dummies and crash tests more real-world, and in turn, lead to the development of vehicle restraints that will improve the safety of children.

Work such as this is helping extend the range of tests that can be done using mechanical dummies, but at the same time, virtual dummies are starting to make their presence known.

For the next few years, simulations with digital dummies are likely to be used to test and hone designs and safety features. Physical crash tests will still need to be done. But virtual crashes should be able to help companies screen out designs that show little or no promise quickly, allowing them to put more effort into safer design features and bring them to market sooner.

Bio: Salvatore Salamone is a senior editor at Ziff Davis Enterprise. He has more than 20 years of experience writing about science and technology for major industry trade magazines and is the author of three business technology books.

The views and opinions expressed in this article are solely those of the author and not necessarily those of Progressive Casualty Insurance Company or its affiliates.