Add On HeadRest

Car accidents account for more than one million whiplash injuries in the U.S. every year. The Add On Headrest is a simple device that can save your neck in the event of a rear end collision. Crash tests performed by experienced accident reconstructionists provide invaluable information in the effort to minimize the pain and suffering of the millions of car accidents victims.

In 1982 the National Highway Traffic Safety Administration reported that integral and adjustable head restraints were 17 and 10 percent effective, respectively, in reducing neck injuries (whiplash). It was determined that head restraints were an effective safety device.

Data from the NASS concluded that between 1988 and 1994, whiplash injuries resulted in a total annual cost of $4.5 billion dollars. According to the IIHS, 1998 projections from State Farm Insurance indicated that whiplash injury claims alone would translate into more than $10 billion dollars annually.

The National Highway Traffic Safety Administration noted that a small improvement in the effectiveness of head restraints could yield large monetary savings.

Add On HeadRest's first low speed, rear impact crash tests were performed using human volunteers at the Highway State Patrol Academy in Columbia, SC on September 11, 1997. Instruction and equipment were provided by Texas A+M's accident reconstruction program and Biomechanical Testing and Research, LLC. Comparison tests using the Add On HeadRest initially showed only a 10 percent improvement over factory head restraints.

Crash tests at the State Patrol Academy, Columbia, SC September 11, 1997

Ten percent was considered pretty good but it fell short of what we were trying to do. This set back led us to further research of car seat and headrestraint designs and the study of hundreds of research papers on the biomechanics of whiplash. After a solid month of research and field testing on hundreds of vehicle makes and models for comfort, our prototype was again ready for the crash tests.

State of the art equipment, accelerometers and computers, are used to accurately measure vehicle speeds, or more specifically the change in velocity of the vehicles. Volunteers wear a head band fitted with an array of accelerometers. Computers process the information and provide data plot graphs showing the G force to the head's center of gravity in various agngular and linear paths. These forces are considered the primary indicators for injury.

The bullet car was a 1980 Chevy Chevette (weight 2,085 pounds). The target vehicle was a 1987 Nissan Maxima (weight 3060 pounds). During both tests the driver was unaware of the specific time of impact,(wore ear plugs and rear view mirror had been removed).

A multitude of information is recorded for each test. The following information was recorded of two comparative tests to evaluate the effectiveness of the Add On HeadRest.

The results marked "Factory" indicate the test without the Add On HeadRest. The results marked "AOHR" represent the test using the Add On HeadRest.

Add On HeadRest Crash Photos Left photo without Add On HeadRest Right photo with Add On HeadRest
High speed film, at 400 frames per second, captured the sequence on the right. In comparison, a home video camera has a film speed of 60 frames per second. The moment of impact was identified by a flash mounted on the driver's door triggered by a switch located on the bumper of the target vehicle.
There is a substantial reduction of the head rotation but more importantly, the relative motion between the head, neck and torso in the test using the Add On HeadRest is minimal.
Reports just released from Chalmers University in Sweden, identified that it is the speed at which the motion occurs which is mostly responsible for the severity and duration of injury.
The following data plot graphs show a remarkable 73 percent reduction of the angular head rotation acceleration and a 38 percent decrease of the resultant linear head acceleration.

Rusty Haight, Auburn, CA Staff Instructor for Texas Engineering Extension Service, Texas A+M University. An accident reconstruction specialist, Rusty is a crash test volunteer and has performed more than 320 crash tests. Here are his comments comparing two similar crash tests, one with the factory headrestraint and the other using the Add On HeadRest.