The agency has explained many times that, in developing crash test dummies for regulatory and research purposes, it seeks to ensure insofar as possible that the measurements obtained on the dummy for measuring injury risk are the same as would be obtained on a human being. In other words, the dummy is used as a surrogate for determining how a human being would fare in a particular crash situation.
As the agency proposes to specify the use of dummies and an out-of-position occupant simulator to test suppression devices, it is similarly necessary to ensure that the test results using these devices will be as close as possible to those that would occur when a human being is present. NHTSA notes, however, that test dummy compatibility with air bag occupant presence and range sensors is not possible in all cases using the currently available dummies. Some technologies, e.g., ultrasonic and active infrared, can be used to recognize human beings but may not recognize current dummies or the out-of-position occupant simulator.
NHTSA notes that it is monitoring research, funded by General Motors, by the Johns Hopkins University Applied Physics Laboratory that specifically investigates and addresses this subject. The project objectives compare the characteristic output signals generated by both human subjects and test dummies, in response to current and projected air bag sensors of the following general types: ultrasonic/acoustic, active infrared, passive infrared, capacitive, and electric field. However, this is a longer-range research project, and is not expected to be completed by the time of the final rule.
Specialized dummy treatments may be required to enable the test dummy and out-of-position occupant simulator to properly interface with the full range of projected sensor technologies. However, it is possible that relatively straightforward surface treatments or clothing selection may suffice for compatibility with ultrasonic and active infrared sensor types.
The agency requests comments on this issue.
