Bracing for impact: Toyota pushes for passenger safety using technology

Around 600 cars are smashed up each year in its Higashi-Fuji Technical Center in Japan alone, with another 1,000 crash tests occurring in other safety centers around the globe. In Higashi-Fuji, Toyota conducts tests on a total of 80 dummies, of which 15 called THOR are state-of-the-art anthropomorphic mannequins made by Humanetics. These units are equipped with sophisticated sensors and cost more than 100 million yen (US$0.91 million) each.

According to Kaye Lim, General Manager of Toyota Motor Asia Pacific’s Public Affairs Department, Toyota spent more than one trillion yen (US$9.2 billion) in 2015 on research and development. “The work at Higashi Fuji is taken very seriously and is of great importance to the development of safety technologies. The Centre has 4,500 employees working on future cars, artificial intelligence, safety, etc., and even has a driving simulator,” she says.  

Ultimately, Toyota’s vision is to completely eliminate traffic casualties through an integrated initiative for safety that considers people, vehicle safety, and the traffic environment. This pursuit for vehicle safety is represented by a three-part cycle where 1) the causes of accident and passenger injuries are analyzed using various accident investigation data; 2) accidents are reenacted in various simulations to create counter-plan technologies; and 3), the effectiveness of such technologies is inspected by assessing any accidents that may occur.

The human element

One way in which Toyota has worked toward this pursuit of real-world safety has been the development of THUMS (Total Human Model for Safety), a virtual human body software that simulates human injuries brought about by vehicle collisions.

Developed in 1997 as a result of the limitations in using dummies for crash test experiments, THUMS simulates the many characteristics of various parts of the human body—from overall shape to bone structure, skin, and even posture; thus, enabling a detailed analysis of bone fractures, severed ligaments, and other injuries that can occur during a vehicle collision.

Toyota has since made great progress with the modelling system, and has been crashing cars—both real and virtual—as part of its experiments.

With THUMS, Toyota is afforded a deeper understanding of the impact of vehicle collisions on the complex nature of the human body, as well as insights on how people instinctively react in dangerous situations. Designed to simulate people of various physiques—a large male; an average male and female; a small female; children aged 10, six and three; a running child aged six; an obese male; and an expectant mother—each THUMS unit is carefully calibrated to represent the respective members’ human body structures to allow for a more thorough internal injury analysis. “Since 1997, THUMS has evolved through five versions which have incorporated face and bone structure, a precise brain model, and detailed modeling of internal organs,” informs Lim.

The latest THUMS Version 5 features an added muscle model that simulates postural states, from relaxed to braced, allowing for a more detailed computer analysis of injuries caused by collisions. “This is an important development because occupant posture has a significant effect on body movement during a collision,” says Lim, adding that current human surrogate models in virtual crash simulations are unable to simulate the reflexive defensive action humans take in the moments before an imminent collision.

“Toyota harnesses the data collected from THUMS to analyze human injury impact and find solutions on how to improve safety technologies to protect the drier, passenger, and even the pedestrian. Over the last few years, THUMS helped improve our side airbag technology, whiplash injury lessening seat, and energy absorbing structures to make cars more pedestrian friendly,” explains Lim.

With every THUMS simulation producing over 100 GB of data,  the software delivers more information on the effects of crashes on the human body than a traditional crash test dummy ever could.

Multi-stakeholder collaboration

To expand its current pool of data, Toyota collaborates with car companies and research institutes in Europe, the United States, and Asia Pacific on test protocol, dummy bio-fidelity, injury mechanism and criteria, and more. The current children members aged 10, six and three, which were added to the THUMS virtual crash dummy software in June 2016, are a result of the collaborative research between Wayne State University, the University of Michigan, and the Collaborative Safety Research Center located in the Toyota Technical Center.

Beyond the Toyota organization, THUMS has been adopted by dozens of companies, including automobile and parts manufacturers. “It is contributing to vehicle safety research all over the world. As of June 2016, we’ve had 81 users of THUMS that comprise car makers and research institutes,” informs Lim.

The software is also increasingly being used in the field of motorsports. Officials from U.S.-based National Association for Stock Car Auto Racing (NASCAR) are using THUMS to investigate a new chest support system for their drivers. “They found their drivers suffer a high number of rib fractures despite being well-protected in the cars. Through THUMS, they were able to develop regulations for seat shapes that are now included in the official rulebook, to reduce the likelihood of rib fractures sustained in drivers as a result of racing accidents,” shares Lim.

Moving forward, Lim conclues, “Toyota will continue exploring possibilities with THUMS to analyze the injuries sustained by both passengers and pedestrians during collisions with and between vehicles, and to further research and improve safety technologies of all kinds.”