Sled Impact Test - Q'Straint - QS 0307

Frontal Impact of the Q8-8100-A-L Wheelchair Tiedown
with 6000 Series L Track Anchorages
Used to Secure the SAE/ISO Surrogate Wheelchair
Loaded with a Midsize Adult Male ATD
Restrained by a Q8-6325-A Three-Point Belt

Tested in accordance with Appendix A of SAE J2249

Submitted to:
Q'Straint
5553 Ravenswood Road
Fort Lauderdale, Florida 33312

The University of Michigan
Transportation Research Institute
2901 Baxter Road
Ann Arbor, Michigan 48109
 

ACKNOWLEDGMENT AND DATA USE RESTRICTION

This test was sponsored by Q'Straint of Fort Lauderdale, Florida, and was conducted in accordance with procedures set forth in Appendix A of SAE J2249 Wheelchair Tiedowns and Occupant Restraint Systems for Use in Motor Vehicles, hereafter referred to as J2249. The performance of the wheelchair tiedown and occupant restraint system has been measured and evaluated according to the requirements of Section 6.2 of this Recommended Practice. Advertisements and marketing literature should refer to the requirements and provisions of SAE J2249, but should not mention the University of Michigan Transportation Research Institute. Requests for copies of this report, test films, and videos should be directed to the test sponsor.

TEST METHODS

This frontal impact test was conducted on the UMTRI impact sled in accordance with Appendix A of SAE J2249. The sled operates on the rebound principle, achieving a desired change in velocity by reversing its direction of motion during the impact event. The sled crash pulse is trapezoidal in shape and is reported as an average deceleration level in g. The sled velocity is monitored immediately before and after impact.

Data generated during the test were digitized live using a workstation and simultaneously multiplexed and recorded on the direct record channels of a Honeywell Model 9600 magnetic tape recorder. All signals were filtered to the requirements of SAE J-211.

The photo-instrumentation consisted of high-speed (1000-frames/sec) digital video cameras for views of the impact event. A Polaroid® graph-check camera was also used to provide a quick-look sequenced photograph of the impact event. A strobe flash and simultaneous voltage pulse record and synchronize the onset of impact deceleration on film, video, and transducer data.
 

TEST SETUP

The SAE/ISO surrogate wheelchair was secured facing forward using the Q'Straint Q8-8100-A-L four-point strap-type tiedown system with 6000 series track anchorages. The tiedown consists of four slider tracks that are bolted longitudinally to the floor of the vehicle to provide front and rear tiedown anchor points, and four retractor-type tiedown assemblies that hook to the wheelchair securement points and anchor to the slider track. The tiedown straps are tightened by turning the knobs on the retractor assemblies until the tiedowns are taut.

The wheelchair was loaded with a midsize-male ATD that was restrained by a Q'Straint Q8-6325-A three-point belt, with the lap belt anchoring to pin-bushing assemblies on the rear tiedown retractors. The upper end of the shoulder belt was anchored to a sled fixture that simulates the vehicle anchor point at the position specified in SAE J2249, and the lower end of the shoulder belt was attached to the pin-bushing connector on the tongue of the Q'Straint lap belt.

The test was conducted using 48-kph (30-mph) and 20-g average impact conditions to determine the frontal-impact response of the Q'Straint Q8-8100-A-L with 6000 series track anchorages and Q8-6325-A three-point belt, and compliance of the WTORS with Section 6.2 of SAE J2249 when dynamically loaded by the surrogate wheelchair and midsize-male ATD. The following table provides further details about the test equipment and setup geometry.

SUMMARY OF TEST SETUP AND PRE-TEST MEASUREMENTS

GENERAL TEST INFORMATION Test number Test date Wheelchair type Wheelchair tiedown Occupant restraint Anthropomorphic Test Dummy (ATD) Wheelchair orientation Sled platform Desired impact velocity (V) Desired average sled deceleration	QS 0307 November 3, 2003 SAE/ISO Surrogate wheelchair Q8-8100-A-L with 6000 series track anchorages mounted longitudinally Q'Straint Q8-6325-A three-point belt Midsize-male ATD @ 76.4 kg (168 lb) Forward facing Rigid steel plate 48 kph (30 mph) 20 g
WHEELCHAIR TIEDOWN Front-to-rear anchor-point distance Rear tiedowns Lateral distance between anchor points Angle wrt horizontal Angle wrt to wheelchair center plane Anchor point to rear-wheel hub Length (anchor point to securement point) Front tiedowns Lateral distance between anchor points Angle wrt horizontal Angle wrt to wheelchair center plane Length (anchor point to securement point)	1289 mm (50.8 in) 356 mm (14.0 in) 37 degrees 0 degrees 394 mm (15.5 in) 495 mm (19.5 in) 813 mm (32.0 in) 40 degrees 24 degrees 508 mm (20.0 in)
OCCUPANT RESTRAINT D-ring location: Behind ATD shoulder Above ATD shoulder Above sled platform Left of wheelchair centerline Angle of pelvic belt wrt to horizontal Angle of shoulder-belt Projected frontal view wrt horizontal Projected lateral view wrt horizontal	305 mm (12.0 in) 178 mm (7.0 in) 1321 mm (52.0 in) 305 mm (12.0 in) 43 degrees 47 degrees, measured on ATD torso 30 degrees, measured above ATD shoulder
ATD POSITIONING Shoulder height above sled platform H-point height above sled platform	1092 mm (43.0 in) 572 mm (22.5 in)
WHEELCHAIR Weight Wheelbase Seatback angle wrt vertical Seatback height (without headrest) Seatpan angle wrt horizontal Seat surface height from floor @ SB junction Seatpan length	85.5 kg (188 lb) 533 mm (21.0 in) 10 degrees 559 mm (22.0 in) 6 degrees 483 mm (19.0 in) 432 mm (17.0 in)

TEST RESULTS

The Q8-8100-A-L wheelchair tiedown with 6000 series L track anchorages effectively secured the SAE/ISO surrogate wheelchair and effectively restrained the ATD during frontal-impact loading and sustained the impact intact. The peak forward excursion of point-P on the surrogate wheelchair was 118 mm, which is below the SAE J2249 limit of 200 mm.

The surrogate wheelchair was in an upright position at the completion of the test, and the ATD was seated in the surrogate wheelchair with the torso leaning to the right approximately 40° to upright. After the test, the surrogate wheelchair could be released from the four-point tiedown and the ATD could be removed from the occupant restraint system without the use of tools.

The ATD was effectively restrained from forward excursions by the Q'Straint Q8-6325-A three-point belt, although the right lap belt webbing severely frayed at the lap belt adjuster/locking mechanism. The peak forward head excursion was 488 mm, which is below the SAE J2249 excursion limit of 650 mm. The peak forward knee excursion was 327 mm, which is below the SAE J2249 excursion limit of 375 mm. The ratio of the ATD's knee excursion to the wheelchair point-P excursion is 2.8, which is above the minimum allowed ratio 1.1.

The results of this test indicate that the Q8-8100-A-L with 6000 series track anchorages and Q8-6325-A three-point belt meets the WTORS frontal-impact performance requirements of Section 6.2 of SAE J2249. The following tables summarize the test results and compliance with SAE J2249.