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 standard. Advertisements and marketing literature should refer to the requirements and provisions of SAE J2249, but should not refer to 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 Pentium-II 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) 16-mm motion-picture cameras and high-speed digital video cameras for side and rear views of the impact event. A Polaroid® graph-check camera was also used to provide a quick-look sequenced photograph of the impact event. The transducer data and the high-speed test films are simultaneously marked by a timing pulse and LED, respectively, generated at one-millisecond intervals. A strobe flash and simultaneous voltage pulse record and synchronize the onset of impact deceleration on film, video, and transducer data.

TEST SETUP

The QRT by Q'Straint Q-8200-A-L with 7000-F track was used to secure the SAE/ISO surrogate wheelchair on the sled platform facing forward. The system consists of four, strap-type tiedowns that hook to the designated securement points on the surrogate wheelchair and anchor to four sections of aluminum track that were bolted to the sled platform.

The wheelchair was loaded with a midsize-male ATD that was restrained by a Q'Straint three-point belt. The ends of the pelvic belt anchored to the retractor assemblies of the rear tiedowns and the upper end of the shoulder belt was bolted to a sled fixture that simulates the vehicle anchor point at the position specified in SAE J2249. The shoulder and pelvic belts were tightened to fit snugly over the ATD.

The test was conducted using 48-kph (30-mph) and 20-g average impact conditions to determine the frontal-impact response of the docking system. The following table provides further details about the test equipment and setup.

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 0105 July 13, 2001 SAE/ISO surrogate wheelchair QRT by Q'Straint Q-8200-A-L with 7000-F track Q'Straint 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) 1283 mm (50.5 in) 419 mm (16.5 in) 33 degrees 0 degrees 432 mm (17.0 in) 495 mm (19.5 in) 699 mm (27.5 in) 36 degrees 17 degrees 483 mm (19.0 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 318 mm (12.5 in) 171 mm (6.8 in) 1257 mm (49.5 in) 305 mm (12.0 in) 45 degrees 62 degrees, measured on ATD torso 28 degrees, measured above ATD shoulder ATD POSITIONING Shoulder height above sled platform H-point height above sled platform 1092 mm (43.0 in) 584 mm (23.0 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 85.0 kg (187 lb) 546 mm (21.5 in) 9 degrees 559 mm (22.0 in) 5 degrees 470 mm (18.5 in) 432 mm (17.0 in)

TEST RESULTS

The QRT by Q'Straint Q-8200-A-L with 7000-F track effectively secured the SAE/ISO wheelchair during frontal-impact loading and sustained impact intact. Forward movement of the surrogate wheelchair was limited to 148 mm which meets the SAE J2249 limit of 200 mm. The surrogate wheelchair was in an upright position at the completion of the test and the ATD seated in the wheelchair. 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 excursion by the Q'Straint three-point pelvic and shoulder belt, and was limited to approximately 405 mm of head excursion and 258 mm of knee excursion, which are both below the SAE J2249 excursion limits of 650 mm and 375 mm, respectively. The ratio of the ATD's knee excursion to the wheelchair point-P excursion is 1.7, which is above the minimum allowed ratio of 1.1.

The results of this test show that the tiedown and occupant restraint system tested meets the requirements of Section 6.2 of SAE J2249. The following tables summarize the test results and compliance with SAE J2249 and ISO 10542 ver 11/99

SUMMARY OF TEST RESULTS

GENERAL TEST INFORMATION Test number Actual impact velocity (V) Actual average sled deceleration level Actual peak sled deceleration level Total time of deceleration over 20 g Total time of deceleration over 15 g Deceleration pulse duration QS 0105 49.6 kph (30.9 mph) 19.3 ms 23.6 ms 27.2 ms 68.4 ms 84.0 ms ATD MEASUREMENTS Peak resultant head acceleration Peak resultant chest acceleration Head Injury Criterion Maximum forward head excursion#134; Maximum forward knee excursion#134;#134; Average post-test H-pt ht above sled platform 37 g 37 g 147 405 mm (15.9 in) 258 mm (10.1 in) 584 mm (23.0 in) 0% change TIEDOWN LOADS Peak left-rear tiedown force Peak right-rear tiedown force 15849 N (3563 lb) 15960 N (3588 lb) BELT LOADS AND PELVIC BELT ANGLE Peak right pelvic-belt load Peak shoulder-belt load Post-test pelvic restraint angle 0 N (0 lb) 8474 N( 1905 lb) 42 degrees WHEELCHAIR MEASUREMENTS #134;#134; Maximum forward wheelchair excursion at Point P* Maximum forward excursion of front-wheel hub Maximum forward excursion of rear-wheel hub 148 mm (5.8 in) 170 mm (6.7 in) 170 mm (6.7 in)

† The forward head excursion is the total forward change in position of the leading edge of the head, measured at the initial position prior to impact and at the time of maximum forward head travel.

†† Excursions reported are the total horizontal change in the position of the affixed targets relative to the sled platform from just prior to impact to the time of maximum forward or rearward excursion.

*Point P is a seating reference point located 50 mm above and 50 mm in front of the junction of the seatback and seat cushion planes.

SUMMARY OF TIEDOWN FRONTAL IMPACT PERFORMANCE
SLED TEST QS 0105