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Ejection Mitigation testing is now required by the U.S. government through FMVSS 226 [1]. FMVSS 226 contains the requirement of using a linear guided headform in a horizontal impact test into the inflated curtain, or other ejection mitigation countermeasure that deploys in the event of a rollover. The specification provides dimensions for a featureless headform [2] but there are limited specifications for the headform skin surface condition. In the “Response to Petitions” of the 2011 Final Rule for FMVSS 226 [3], the NHTSA declined the option to include a headform cleaning procedure. This research presents a case study to quantify the effect of changes in the friction between the headform and curtain on the measured excursion. The study presented here shows that a change in friction between the headform and curtain can affect excursion values by up to 135 millimeters (mm).

Federal Motor Vehicle Safety Standard 226 outlines a component test methodology that consists of a linear impact test that uses a featureless head-form with a mass of 18 kg to impact a vehicle's side windows' daylight openings at various positions. The test measures the excursion of the head-form beyond the plane of the window glazing. The intention is to evaluate the ability of a vehicle's ejection mitigation system, such as the curtain airbag or other vehicle features, to manage the impactor energy and limit excursion. However, there are several factors which may cause variation in the amount of excursion measured in the test. These factors include how the vehicle is restrained for the test, the friction of the linear impactor shaft and the lateral deflection of the impactor shaft among others.

This paper describes a new test methodology for simulating a near side oblique pole impact per FMVSS 214. Given the complexity, time, and cost of using full vehicle crash tests to develop occupant restraint systems, it is desirable to have a simple test method that allows engineers to develop an optimized restraint system in a timely and cost effective manner. The authors will present a new sled test method that accurately simulates a full vehicle oblique pole side impact test using only minimal vehicle components. This test method was validated through correlation with vehicle testing using the SID IIs (5th percentile female) and the ES2-RE (50th percentile male) dummies, on both a sport utility vehicle (SUV) and mid sized sedan to show application of this test method to a wide range of vehicle architectures.