Search Results

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.

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 summarizes a series of matched-pair frontal sled tests using the Test device for Human Occupant Restraint 50th Percentile Male (THOR-50M) anthropomorphic test device (ATD). Testing was conducted to compare the response of an ATD equipped with an on-board data acquisition system (DAS) to that of one equipped with an off-board system. Sled testing was performed using a modified version of NHTSA’s Gold-Standard test method consisting of a generic buck with a ridged seat and a 3-point seatbelt system. Eight tests were conducted, all using a common generic 30 km/h crash pulse with a peak deceleration of 9 G’s, and a 2.5 kN load limiting 3-point seatbelt retractors without pretentioners. Four tests were conducted with each ATD, two tests with a left shoulder belt routing and two with a right shoulder belt routing to allow for evaluation of the ATD repeatability under each belt routing.

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).

The National Highway Traffic Safety Administration (NHTSA) has identified ejection mitigation as a top priority, issuing a final rule for FMVSS 226, Ejection Mitigation, in January of 2011 to set performance standards for a vehicle's ejection mitigation countermeasures to mitigate the risk of ejection through a vehicle's side window openings. The most likely countermeasures to be used for compliance with this standard are rollover activated curtain airbags that deploy from a vehicle's roof rail. However, this rule will most likely result in increases in the coverage area and inflator outputs of the curtain airbag; which may influence out-of-position occupant injury as measured in the test methods that have been outlined by the Side Airbag Out-of-Position Injury Technical Working Group (TWG).