[Federal Register Volume 65, Number 63 (Friday, March 31, 2000)]
[Rules and Regulations]
[Pages 17180-17196]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-7955]
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DEPARTMENT OF TRANSPORTATION
National Highway Traffic Safety Administration
49 CFR Part 572
[Docket No. NHTSA-00-7052]
RIN 2127-AG78
Anthropomorphic Test Devices; 12-Month-Old Child Dummy
AGENCY: National Highway Traffic Safety Administration (NHTSA),
Department of Transportation.
ACTION: Final rule.
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SUMMARY: This document adopts design and performance specifications for
a new 12-month-old infant dummy. The new dummy is especially needed to
evaluate the effects of air bag deployment on children who are in rear-
facing child restraints installed in the front passenger seat of
vehicles. It will also provide greater and more useful information in a
variety of crash environments to evaluate child safety. Adopting the
dummy is a step toward using it in the tests we conduct to determine
compliance with our safety standards. The use of the dummy in our
compliance tests is being addressed in separate rulemaking proceedings.
DATES: The amendment is effective on May 30, 2000. The incorporation by
reference of certain publications listed in the regulations is approved
by the Director of the Federal Register as of May 30, 2000.
Petitions for reconsideration of the final rule must be received by
May 15, 2000.
ADDRESSES: Petitions for reconsideration should refer to the docket
number and notice number of the notice and be submitted to:
Administrator, room 5220, National Highway Traffic Safety
Administration, 400 Seventh Street, SW., Washington, DC 20590.
FOR FURTHER INFORMATION CONTACT: For nonlegal issues: Stan Backaitis,
Office of Crashworthiness Standards (telephone: 202-366-4912). For
legal issues: Deirdre R. Fujita, Office of the Chief Counsel (202-366-
2992). Both can be reached at the National Highway Traffic Safety
Administration, 400 Seventh St., S.W., Washington, D.C., 20590.
SUPPLEMENTARY INFORMATION: This document amends our regulation for
Anthropomorphic Test Devices (49 CFR Part 572) by adding Subpart R,
containing specifications for a new, more advanced 12-month-old infant
test dummy. The new dummy is more representative of humans than the
dummies representing younger infants in Part 572, and allows the
assessment of the potential for more types of injuries in automotive
crashes. The new dummy can be used to evaluate the effects of air bag
deployment on children in rear-facing child restraints and potentially
on out-of-position children, and can provide a fuller evaluation of the
performance of child restraint systems in protecting young children.
NHTSA has already specified a number of child test dummies in Part
572, including dummies representing a newborn, a 6-month-old and a 9-
month-old child (subparts K, D and J, respectively). The dummies have
been used to test child restraint systems to the requirements of
Federal Motor Vehicle Safety Standard No. 213 (49 CFR 571.213). These
test devices enable NHTSA to evaluate motor vehicle safety systems
dynamically, in a manner that is both measurable and repeatable.
Today's final rule is part of NHTSA's effort to add to and improve
the child dummies specified in Part 572. We recently amended Part 572
to add new, more advanced, Hybrid III-type test dummies representing a
6-year-old and a 3-year-old child. Together with the dummy adopted
today, the new child test dummies will be used in tests we are
specifying in our occupant crash protection standard (49 CFR 571.208)
to assess the risks of air bag deployment for children, particularly
unrestrained,
[[Page 17181]]
improperly restrained, and improperly located children. The new child
test dummies may also be incorporated into Standard No. 213 (49 CFR
571.213) for use in compliance testing of child restraint systems.
Today's final rule only concerns adding the new 12-month-old dummy to
Part 572. Issues relating to whether this and the other new dummies
should be incorporated into the compliance tests for the motor vehicle
safety standards are being addressed in separate rulemaking actions.
Summary of Final Rule
The 12-month-old dummy was developed as a child restraint air bag
interaction dummy (hereinafter referred to as the CRABI 12 dummy). Its
specifications consist of a drawing package that shows the component
parts, the subassemblies, and the assembly of the complete dummy. It
also defines materials and material treatment processes for all the
dummy's component parts, and specifies the dummy's instrumentation and
instrument installation methods. In addition, there is a manual
containing disassembly, inspection, and assembly procedures, and a
dummy drawings list. These drawings and specifications ensure that the
dummies will vary little from each other in their construction and are
capable of consistent and repeatable responses in the impact
environment. The parts list and drawings are available for inspection
in NHTSA's docket (room 5108, 400 Seventh St., S.W., Washington, D.C.
20590, telephone (202) 366-4949). (We are using NHTSA's docket because
the drawings cannot be electronically scanned into the DOT Docket
Management System.) Copies may also be obtained from Reprographic
Technologies, 9000 Virginia Manor Road, Beltsville, MD 20705;
Telephone: (301) 210-5600.
In addition to the drawings and specifications, we are establishing
impact performance criteria for the CRABI 12 dummy. These criteria will
serve as calibration checks and further assure the kinematic uniformity
of the dummy and the absence of structural damage and functional
deficiency from previous use. The criteria address head, neck, and
thorax impact responses. This rule does not adopt the torso flexion
requirements that we had proposed.
We have adopted generic specifications for all of the dummy-based
sensors. For dummies incorporated into Part 572 in years past, the
agency specified sensors by make and model. However, we believe that
approach is unnecessarily restrictive and limits innovation and
competition. Accordingly, consistent with the new approach taken for
the sensors for the new Hybrid III-type 3-year-old, 6-year-old child
and 5th percentile female adult dummies, we are adopting generic
specifications for the sensors. These generic specifications reflect
performance characteristics of sensors used in our evaluation tests of
the dummy, which are identified by make and model in a NHTSA technical
report ``Development and Evaluation of the CRABI 12-month-old Infant
Dummy.'' A copy of this report is in the docket for the notice of
proposed rulemaking that we published for this final rule (Docket No.
99-5156). Those sensor characteristics were also the basis for our
discussions with a special task force of the SAE J211 Instrumentation
Committee concerning the dummy.
Background
Air bag fatalities of children have raised serious concerns about
how best to evaluate the safety of children in a variety of crash
environments. We have been working with the automotive industry to
assure greater safety in motor vehicles through the development,
evaluation and application of significantly improved occupant
protection technologies. As part of our overall program to achieve
greater safety, we have sought to evaluate, for possible inclusion into
our safety standards, new and improved test devices to evaluate the
relationship between observed injuries and the forces causing them. One
of the new test devices is a 12-month-old infant dummy.
The dummy was developed through the efforts of the Society of
Automotive Engineers (SAE) Child Restraint Air Bag Interaction (CRABI)
Task Force. The CRABI Task Force had determined that a new infant dummy
was needed for testing and evaluating the effects of child restraints
and air bags, as well as their interaction, on infants. The new dummy
had to be capable of evaluating both rear facing and forward facing
child restraints, as well as the injury potential of air bags on out-
of-position children.
The SAE subsequently developed a 12-month-old infant dummy. The
dummy's initial configuration and biomechanical response corridors were
based on anthropometry and mass distribution of 12-month-old infants
and on scaling techniques from the larger size Hybrid III-type dummies.
The scaling reflected differences in geometry and dimensional
characteristics of particular body segments and their elastic
properties. Our initial evaluation of the dummy in 1996 revealed some
structural and performance deficiencies which the SAE later remedied
with substantial modifications to the dummy. The dummy continued to be
modified until September 1998.
In the latter part of 1998, based on the results of an agency test
program evaluating the 12-month-old dummy, we tentatively concluded
that the dummy was ready for incorporation into Part 572. On March 8,
1999, we published an NPRM proposing to incorporate the CRABI 12 dummy
into Part 572 as Subpart R, and invited comments (64 FR 10965)(Docket
NHTSA-99-5156). The original 45-day comment period was extended on
April 22, 1999, to June 22, 1999 (64 FR 19742), in response to a
request for an extension of the comment period.
Comments on the NPRM
We received comments from seven organizations and one individual:
Robert A. Denton, Inc. (Denton), TRW Vehicle Safety Systems Inc. (TRW),
Advocates for Highway and Auto Safety (Advocates), Toyota Technical
Center, USA, Inc. (Toyota), Transportation Research Center, Inc. (TRC),
the Alliance of Automobile Manufacturers (Alliance), the SAE Dummy
Testing Equipment Subcommittee (DTES), and Gelsys Perez, a private
citizen. General Motors (GM) submitted test data to the docket for this
rulemaking on January 25, 2000.
Advocates and Gelsys Perez expressly supported the incorporation of
the CRABI 12 dummy into our regulations. The Alliance, Toyota, and
Denton (a manufacturer of load cells used in crash dummies) generally
supported the proposal with technical comments to correct or clarify
various specifications in the regulatory text proposed for the dummy.
TRC and TRW commented on technical aspects of the proposal. GM
submitted neck calibration test data to supplement data provided by the
Alliance. In general, the comments addressed the following issues:
calibration requirements and procedures, instrumentation
specifications, dimensional changes to dummy drawings, and the dummy's
user's manual.
In addition to comments on specific aspects of the proposal, TRW
suggested that it is premature for the agency to proceed with
rulemaking and suggested ``a delay of at least 12 months to allow the
industry time to test the dummy * * * to assess the appropriateness of
the dummy as a compliance tool.'' TRW believes that the industry has
had insufficient time to test the CRABI 12 to ascertain performance and
reliability
[[Page 17182]]
due to the unavailability of the latest dummy configuration from the
manufacturer. The commenter contends that it has been unable to test
the dummy under the requirements proposed in the agency's advanced air
bag rulemaking (Docket NHTSA 98-4405, Notice 1) and therefore cannot
make judgments as to the suitability of the CRABI 12 dummy for these
test conditions.
We do not agree that this rulemaking should be delayed a year.
Since the issuance of the NPRM, TRW has had sufficient time to procure
a dummy and conduct enough tests to assess the dummy's appropriateness
as a compliance tool. The dummy specified today differs very little
from the dummy specified in the NPRM. There has been an ample supply of
the dummy for parties to test and a sufficient amount of time to test.
Since publication of the NPRM, GM has tested two dummies and has
submitted its data to the docket (see 99-5156-14). Delaying this
rulemaking would postpone use of the dummy in our compliance tests
evaluating the injury causing potential of air bags on infants. Because
the dummy has been shown to be a reliable test instrument time after
time in rigorous testing, as discussed in a technical report cited in
the NPRM,\1\ we believe that delays in using the dummy for evaluating
the safety of air bags cannot be justified.
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\1\ ``Development and Evaluation of the CRABI 12-Month-Old
Infant Crash Test Dummy (January, 1999 version).''
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Calibration Requirements and Procedures
Head
To calibrate the dummy's head, the agency proposed requirements for
the head's response in drops onto the forehead and onto the rear of the
head (Sec. 572.152). The head response on the forehead was proposed to
be unimodal (i.e., consisting of an acceleration-time curve which has
only one prominent peak) and not less than 100 g or more than 120 g;
the response on the back of the head was proposed to be not less than
55 g or not more than 71 g. The regulatory text proposed for the CRABI
12 dummy stated that the resultant acceleration versus time history
curve shall be unimodal, and the oscillations occurring after the main
pulse must be less than 10 percent of the peak resultant acceleration.
In its comments, TRW states that results from head drop tests
indicate that a 10 percent limit on subsequent peaks after the first
peak resultant acceleration is not sufficient for the dummy. TRW
believes that none of the data presented by the agency, except for one
rear impact test, met the 10 percent oscillation limit of the peak
resultant head acceleration. The commenter suggests that a 15 to 20
percent oscillation limit of subsequent peaks would be more
appropriate.
Similarly, TRC (a test facility that uses and calibrates test
dummies) notes that the oscillation requirement should be changed
because the 10 percent-of-peak definition does not fit the data beyond
the primary peak. The commenter further states that truncating the time
frame does not seem advisable. The commenter provided test data
consisting of two head drop resultant acceleration plots, one front and
one rear, that illustrate typical curves which have second or third
peaks exceeding 10 percent of the first peak. The commenter states that
the DTES has determined that 17 percent for front and 16 percent for
rear would be more appropriate and suggests changing the requirement to
reflect these values.
The Alliance also believes that the 10 percent limit on subsequent
oscillations cannot be met. The commenter suggests that a limit of 20
percent is appropriate.
We agree that the 10 percent oscillation limit should be widened
for this dummy. We proposed the 10 percent unimodal requirement based
on our experience with dummies having metallic skulls. However, the
CRABI 12 dummy's head has a non-metallic skull which responds in drop
tests with a lower natural frequency and with less structural damping
than heads with aluminum skulls,\2\ which makes it more difficult to
meet the 10 percent limit on oscillatory responses. Upon reevaluation
of our test data, we agree that oscillatory head accelerations
following the primary response peak could be as high as 14.5 percent in
frontal impacts and 13.6 percent in rear impacts, as compared to an
aluminum skull (with a vinyl skin cover) at less than 10 percent.
Considering the head drop test data on a statistical basis, values of
subsequent accelerations at 2 standard deviations (s.d.) could result
in oscillation peaks as high as 16.4 percent in frontal impacts and
15.4 percent in rear impacts. Accordingly, this final rule specifies
that for both frontal and rear head drop tests, oscillations occurring
after the main pulse must be less than 17 percent of the peak resultant
acceleration.
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\2\ We do not believe the lower natural frequency of this
dummy's head has any significant consequences on the test results,
unless the dummy's head was going to impact rigid objects. Test
results in a variety of child restraints with and without head
impact as well as in air bag out-of-position deployments did not
indicate any resonance-associated problems that would have affected
the impact measurements.
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The regulatory text proposed for the CRABI 12 dummy specifies in
section 572.152(c)(5) a two-hour wait between successive tests on the
same head. TRC suggests that the waiting period should be changed to
apply only to successive tests on the same side of the head (front or
rear). We agree that the two-hour waiting time need apply to only head
drops on the same side. The skin on the head needs a recovery period
between tests, but a recovery time is not needed if the test is
conducted on the opposite sides of the head. Thus, to allow testing of
the head to proceed more expeditiously, this rule specifies that the
two-hour waiting period applies to successive tests of the head
assembly ``at the same impact point.''
Neck Flexion and Extension
For calibration, the agency proposed a pendulum mounted headform-
neck assembly impact test and corresponding neck flexion and extension
performance requirements (Sec. 572.153).
Neck Flexion Calibration Requirements
For flexion, the regulatory text proposed for the CRABI 12 dummy
stated that:
(1) plane D of the headform must rotate in the direction of
preimpact flight with respect to the pendulum's longitudinal centerline
not less than 75 degrees and not more than 89 degrees occurring between
42 milliseconds (ms) and 56 ms from time zero; (2) the peak moment
about the occipital condyles must not be less than 37 Newton meters (N-
m) and not more than 45 N-m occurring within the minimum and maximum
rotation interval; and (3) the positive moment shall decay for the
first time to 5 N-m in the time frame between 60 ms and 80 ms.
TRW, TRC and the Alliance suggest that according to DTES-compiled
data, some of the proposed calibration corridors need to be adjusted to
incorporate a larger sampling of tested necks. The commenters recommend
the following adjustments: Maximum rotation between 75 and 86 degrees;
time at peak rotation between 49 and 57 ms; peak moment during the
specified rotation interval not less than 34 and not more than 47 Nm;
and moment decay time to 5 N-m (from time zero) not less than 66 and
not more than 78 ms. The commenters state that these corridors are
based on the statistical average of the DTES data two
standard deviations.
Maximum rotation. We are lowering the upper limit of the headform
peak rotation corridor by three degrees from
[[Page 17183]]
the proposal of 89 degrees to 86 degrees while retaining the lower
limit at 75 degrees. The suggested narrower rotation range is based on
a statistical analysis of a much larger data base than that available
to the agency at the time the NPRM was published and thus is likely to
be more representative of actual performance. Further, it limits
variability to approximately 7 percent which is in the ``good''
performance range. It also is in agreement with the range proposed by
the commenters.
Time at peak rotation. The regulatory text proposed for the CRABI
12 dummy specified headform rotation versus time requirements in
Sec. 572.153(b)(1)(i) that were identical in concept to the
requirements for the 3-year-old child dummy specified in Subpart C of
Part 572. TRW, TRC and the Alliance suggested changes to the
requirements. Upon further consideration, we have decided to delete the
headform rotation versus time requirement altogether. When the Subpart
C dummy was added to Part 572 in 1979, a means of measuring bending
moments in the neck and combining them with the motion of the head was
not available. However, in 1991 a moment-measuring load cell became
available for this dummy. With the availability of a six-axis load cell
for the CRABI 12 dummy, it became possible to measure the peak moment
and to relate it to the rotation of the headform. This made the
headform displacement-rotation versus time requirement redundant. We
believe that specifying a minimum-maximum peak moment within a maximum
headform rotation window is sufficient to control the dynamic
properties of the neck (to control head kinematics), and that headform
rotation in time requirement would serve no purpose. Accordingly, this
final rule does not adopt the proposed headform rotation versus time
requirements.
Peak moment during rotation interval. TRW, TRC and the Alliance
suggested that the proposed peak moment of 37-45 N-m within the maximum
headform rotation corridor should be revised to a range between 34 and
47 N-m. The commenters indicate that the recommendation of the wider
peak moment corridor is based on DTES-compiled data 2 s.d.
However, they do not indicate if the moments listed by DTES were peak
moments at the maximum headform rotation or peak moments within the
allowed time corridor. Upon receiving these comments, we reviewed the
DTES reported data summary in Attachment 11 of the DTES meeting minutes
of April 14, 1999 (a copy of which is in the docket for the NPRM,
Docket 99-5156). The data indicate that the average performance for 23
necks was 40.19 N-m a 2.31 s.d., leading to a response
range of 35.56 N-m to 44.81 N-m. It is accepted practice in the
biomechanics community to judge the adequacy of a component's
variability in subsystems tests as 0-5% being in the excellent range,
5-8% good, 8-10% marginally acceptable and above 10% not acceptable.
Using the 10% value as the maximum allowable variability and rounding
the values to the lowest and the highest next numbers, we believe that
the existing data support neck performance at 36 N-m at the lower limit
and 45 N-m at the upper limit. We are accordingly specifying that
range.
Moment decay time to 5 N-m (from time zero). TRW, TRC and the
Alliance suggested reducing the time corridor for the positive moment
decay at the first 5 N-m from the proposed range of 60-80 ms to 66-78
ms. While these test value recommendations are supported by the test
data, we believe the data sample is still too small to justify the
adoption of narrower corridor limits. Also, we do not know how
narrowing the corridor might affect the rejection rate of manufactured
necks. Further, we see no evidence that narrowing the corridor would
lead to better performing necks. Accordingly, we are adopting the time
duration for moment decay as proposed in the NPRM.
TRC suggested that the requirements be clarified to specify that
the peak moment occurs during the time the angle is between the
``passing'' head displacement-rotation limits, rather than time limits.
The commenter also suggested it would be clearer to specify that the
moment of interest is not the Y-axis moment which reads directly from
the load cell, but is a calculated moment reflecting its correction to
the occipital condyle. TRC suggested including the actual equation for
moment calculation.
The regulatory text proposed for the CRABI 12 dummy specifies in
section 572.153(b)(1)(ii) that the moment is to be calculated about the
occipital condyle. While the proposed regulatory text does not
expressly provide the equation to be used, the proposed text
incorporates by reference SAE J1733 ``Sign Convention for Vehicle Crash
Testing,'' which includes the equation for moment calculation. The
document also defines the proper polarities of the signal measured in a
crash test which are critical to the calculation of the moment about
the occipital condyle. Nonetheless, because the regulatory text for the
Hybrid III-type 6-year-old child and 5th percentile female adult
dummies include an equation for moment calculation, we have added the
equation to the text for the CRABI 12 dummy. Accordingly this final
rule adopts the following language in new Sec. 572.153(b)(1)(iii):
``The moment shall be calculated by the following formula: Moment (Nm)
= My-(0.005842m) x (Fx), where My is the moment about the y-axis, Fx is
the shear force measured by the neck transducer (drawing SA572-S23) and
0.005842m is the distance from the point at which the load cell
measures the force to the occipital condyle.''
Neck Extension Calibration Requirements
For extension, the regulatory text proposed for the CRABI 12 dummy
specified that: (1) Plane D of the head must rotate in the direction of
preimpact flight with respect to the pendulum's longitudinal centerline
not less than 78 degrees and not more than 90 degrees occurring between
58 ms and 66 ms from time zero; (2) the peak negative moment about the
occipital condyles must have a value not more than -11 N-m and not less
than -23 N-m occurring within the minimum and maximum rotation
interval; the negative moment shall decay for the first time to -5 N-m
in the time frame between 78 and 90 ms after time zero.
TRW, TRC and the Alliance, referring to DTES data, indicate that
some of the calibration corridors need to be adjusted to reflect a
larger sampling of tested necks. These commenters believe that the neck
extension calibration corridors be based on DTES-developed values as
follows: Maximum rotation should be 81-92 degrees; time at peak
rotation should be 67-78 ms; peak moment during the specified rotation
interval should be -12 to -23 Nm; and moment decay time to -5 N-m (from
time zero) should be 76-84 ms. The commenters state that these
corridors are based on the statistical average of the DTES data
2 s.d.
Maximum rotation. The three commenters recommended adjusting the
headform peak rotation corridor from the proposed 78-90 degree range to
81-92 degrees. Our review of the furnished additional data support an
upward shift of the proposed range. However, the data also show that
the lower limit should be set at 80 degrees rather than at 81 degrees.
Setting the limit at 81 degrees would fail a greater number of necks,
even though those necks would be considered satisfactory on a
statistical basis. Accordingly, the new rotation corridor is set at 80-
92 degrees.
Time at peak rotation. The regulatory text proposed for the CRABI
12 dummy specified headform extension rotation versus time requirements
in
[[Page 17184]]
Sec. 572.153(b)(2)(i) that were identical in concept to the
requirements for the 3-year-old child dummy specified in Subpart C of
Part 572. As discussed in the previous section on neck flexion
requirements, we believe that specifying a minimum-maximum peak moment
within a maximum headform rotation window is sufficient to control the
dynamic properties of the neck (to control of head kinematics) without
the need to establish redundant specifications for headform rotation
versus time. Accordingly, this final rule does not adopt the proposed
headform rotation versus time requirements.
Peak moment during rotation interval. The three commenters
suggested that the NPRM's proposed peak moment of -11(-)-23 N-m within
the maximum headform rotation corridor should be revised to -12(-)-23
N-m. Based on our analysis of all of the available test data, we agree
with the suggestion to reduce the width of the peak moment corridor,
and accordingly adopt acorridor of -12(-)-23 N-m.
Moment decay time to 5 N-m (from time zero). TRW, TRC and the
Alliance suggested that we reduce the time corridor for the negative
moment decay at the first -5 N-m from 78-90 ms to 76-84 ms. We agree
that the data show that the lower limit of the time corridor should be
lowered to 76 ms. However, we see no benefit in narrowing its range.
Narrowing the range would fail a greater number of necks, even though
those necks perform satisfactorily in all other respects. The
commenters have not provided nor do we have any evidence that a
narrower corridor at 76-84 ms would lead to better performing necks.
Accordingly, this final rule reduces the lower limit to 76 ms while
retaining the upper time limit at 90 ms.
In response to TRC's comment, as we did with regard to the neck
flexion requirements, this final rule adopts new section
572.153(b)(2)(iii) to set forth the equation for calculating the
moment. The reason for adding the equation is to clarify how the moment
is calculated.
Issues Relating to Neck-Headform Test Procedure
The proposed regulatory text for the CRABI 12 dummy stated in
Sec. 572.153(c)(4)(i) that ``Time zero is defined as the time of
initial contact between the pendulum striker plate and the honeycomb
material. The pendulum accelerometer data channel should be at the zero
level at this time.''
Toyota suggests that all data channels for the neck extension and
flexion tests be set at the zero level at time zero, rather than only
the pendulum accelerometer data channel, as was done for the Hybrid
III-type 6-year-old and 5th percentile adult female dummies. We
disagree. The CRABI 12 dummy neck is considerably more flexible than
those of the 6-year-old and 5th percentile female adult dummies. As a
result, the head-neck complex of the CRABI 12 dummy experiences
considerable pre-impact kinematic lag as the pendulum accelerates
downward towards the vertical. If all data channels, including rotation
and moment channels, were made zero at impact, as Toyota suggests, the
pre-impact neck rotation lag would not be accounted for in the total
rotation of the neck, which would not be in line with the method by
which biomechanical moment-rotation corridors were established.
The neck biomechanical response corridors were based on ``flexion''
and ``extension'' kinematics, or forward and backward bending of the
neck from its neutral position, respectively, due to inertial forces of
the head. In order to measure true flexion and extension of the dummy
during calibration tests, the zero level of the data channels must be
established prior to initiation of the drop test, when the longitudinal
centerlines of the neck and pendulum are parallel to each other, i.e.,
when the pendulum hangs down in a vertical position. The pendulum
accelerometer data channel, on the other hand, must be zeroed at time
zero (the instant the pendulum engages the hexcell) in order to get the
correct integrated velocity curve from which the velocity readings are
taken at specific time intervals. Accordingly, as proposed in the NPRM,
the final rule retains the time zero setting procedure for the pendulum
data channel, but not for the neck data channels.
Toyota requested that the regulatory text specify a 30-minute
recovery time between successive neck tests. The proposed regulatory
text in Sec. S572.156(m) specified a separation of 30 minutes between
performance tests of the same component, segment, or assembly, which
includes the neck. Accordingly, no change is needed to meet Toyota's
concerns and the text is adopted as proposed.
Thorax
For calibration, we proposed a thorax response corridor in terms of
peak resistance force exerted by the dummy's sternum on the penetrating
impactor. The regulatory text proposed a peak force response corridor
between 1600 N and 1700 N.
TRW, TRC and the Alliance believe that there is no need for this
test. TRW states that the thorax consists of a rigid steel substructure
with a foam pad attached to it. ``Since there are no moving parts
within the chest area as well as no method by which chest displacement
can be measured, a dynamic calibration test would seem inappropriate.''
TRW suggests that if NHTSA believes that a test is needed to check the
foam pad, a standard ASTM compression test would be more appropriate.
Further, TRW states that the proposed corridor of 1600 to 1700 N is not
accurate because it was developed based on only four tests conducted on
a single dummy. TRW's tests of its own dummy found that the average
peak resistive force was 1830 N.
TRC states that the dummy was designed with no deflecting rib
components and that a ``torso impact test when there is no chest
deflection to measure gives little data; the compression
characteristics of the foam can be determined without a dynamic test or
by simply spelling them out as a manufacturer's specification of foam
density/compression characteristics.'' The Alliance states ``It is our
belief that the performance of the thorax in impact is best assured by
specifying the ratio of the reactants for the foam from which the
insert is molded, the method used by the manufacturer of the dummy. The
foam-in-place reactant ratio is adjusted until a test block of the
material exhibits the required compression force-deflection
characteristic. The insert is then molded from the same mix of
reactants.''
We do not agree with the suggestion to abolish the proposed thorax
impact response requirement. In each of the Federal motor vehicle
safety standards that use test dummies in compliance tests, one of the
key injury assessment parameters is the thorax acceleration response.
The suggestion that a periodic inspection test can be used in place of
the proposed thorax impact test provides no assurance that the
available material in conjunction with the supporting thorax structure
will be capable of consistent and repeatable impact response. This
assurance is particularly needed for thorax impacts because foams
degrade with the number of test applications, different loading levels,
and time. We do not know of any ASTM load-deflection tests for foams
that would consistently correlate with dynamic-impact responses as
installed and used on the dummy over time, and no information on that
issue has been provided by the commenters. Accordingly, we are adopting
a dynamic impact response requirement in the regulatory text for the
CRABI 12 dummy.
The Alliance and TRW disagree with the peak force measurements
proposed
[[Page 17185]]
in the regulatory text for the dummy. The Alliance suggests revising
the thorax impact specification from the proposed 1600-1700 N level to
1526-1880 N. While TRW states that it ran impact tests on its own dummy
and found the average peak resistance force to be 1830 N, TRW did not
provide data to support this claim. Data in the minutes of the DTES
meeting of June 2, 1999, provide a compilation of impact test results
from three groups of dummies tested at three different facilities. The
average response value for those test was 1695 N with a s.d. of 89 N,
suggesting a response corridor, based on 2 s.d., between 1517 N and
1872 N. The majority of the data (16 dummies) were from FTSS, and three
were from other users.
An indication of what can be expected from a reasonably controlled
batch of foams is found in early data from the combined NHTSA and FTSS
tests, as reported in DTES minutes of April 14, 1999. NHTSA tested one
dummy and FTSS tested three. These tests yielded an average response of
1670 N with a s.d. of 63. Subsequently reported data from General
Motors (DTES minutes of June 2, 1999), based on two dummies, yielded an
average response 1622 N with an s.d. of 54. The latter two test series
suggest corridor widths based on 2 s.d. at 1544-1796 N for the former
and 1514-1730 for the latter. Based on these two test series, we
believe that with some controls at the dummy manufacturer level, the
dummies can meet a response range of 1514-1796 N. This suggested
corridor would be larger than that proposed in the regulatory text, but
it would reflect a more realistic data base, and it would be in the
good to marginal acceptance range at 8.5 percent.
TRC states that the pendulum used in the thorax impact test should
be specified in ``generic'' terms. We agree. In response to similar
comments in our rulemakings on the Hybrid III-type 3-year-old, 6-year-
old and 5th percentile adult female dummies, we have developed generic
impactor specifications for those new dummies. Similar to what we have
done with respect to the impactor specifications in those rulemakings,
this final rule describes the thorax impactor using generic
specifications.
TRC suggests that the positioning of the dummy in the thorax
assembly test procedure needs to be modified to match the placement
shown in proposed Figure R5. The proposed regulatory text
(Sec. 572.154(c)(3)) stated that the dummy is positioned with fingers
barely touching the seating surface plane. However, Figure R5 showed
the dummy's fingers as well above the seating surface. We agree that
the dummy's arms are too short for the fingers to touch the seating
surface plane and have made the necessary corrections to
Sec. 572.154(c)(3).
The regulatory text proposed for the CRABI 12 dummy specifies that
the dummy is dressed in a light-weight cotton stretch short-sleeve
shirt and above-the-knee pants for the thorax impact test
(Sec. 572.154(c)(2)). TRC states that these specifications for the
clothing do not match the drawing package for the dummy. The commenter
also states that it believes that all tests of the dummy have been run
with the dummy in long-sleeved and ankle length clothing. Upon
reviewing our testing experience with the dummy, we agree that the
clothing that has been used consisted of long-sleeved shirt and long-
legged pants. We have revised the paragraph in question to refer to
such clothing, and have included a limit on how much the clothing may
weigh. That specification more precisely describes the clothing that is
used on this dummy.
Torso
The regulatory text proposed for the CRABI 12 dummy specified in
Sec. 572.155 the following torso flexion test and performance
requirements: (1) When the torso is flexed 45 degrees from vertical,
the resistance force must not be less than 90 N and not more than 120
N, and (2) upon removal of the force, the upper torso assembly returns
to within 10 degrees of its initial position.
TRW, TRC and the Alliance question the need for this procedure in
view of the anticipated use of the CRABI 12 test dummy in compliance
tests. These commenters believe that the dummy will likely be used only
when restrained in a rear-facing child restraint system, and thus there
is no need to determine the flexion articulation between upper and
lower halves of the torso assembly. The commenters suggest that
periodic inspections would be adequate to assure the dummy's
performance instead of a calibration test.
While we agree with the commenters that the dummy in crash tests
will likely be restrained in a rear-facing child restraint, we had
proposed the torso flexion test primarily to address an overall
variability problem. At the time the NPRM was issued, we believed that
a dummy's torso flexion stiffness could substantially influence the
variability of the dummy's impact response when the dummy's upper torso
moved considerably with respect to the lower half of the torso. In
response to the comments received on this issue, we conducted
additional sled tests in January 2000 and found that the dummy's
response variability we had initially observed was caused by
insufficient support of the child restraint seat back on the standard
seat assembly. Once the child restraint was provided sufficient
support, there was a substantial reduction in the dummy's impact
response variability. (We have placed a report of this testing in the
docket for this final rule.) Accordingly, we agree with the commenters
that the torso flexion stiffness test is not needed, and that periodic
inspections will be adequate to assure the dummy's structural integrity
and performance consistency. Such inspection will be included in the
Procedures for Assembly, Disassembly and Inspection (PADI) document
(see discussion below on the PADI). Accordingly, we have not adopted
the torso flexion requirement as proposed in Sec. 572.155.
Other Issues Relating to Calibration Requirements and Procedures
Post-Test Calibration Requirement
The Alliance suggests that the specifications for the CRABI 12
dummy should include a requirement that the dummy meet calibration
specifications following a NHTSA compliance test. The commenter states
that Part 572 has such a requirement for dummies adopted in years past,
while recent rulemakings on the new Hybrid III-type 3-year-old, 6-year-
old, and 5th percentile female adult have not included such a
requirement. The Alliance believes that the post-test dummy state of
compliance is very important because test results indicating a
noncompliance may be dummy-related. Without post-test dummy
verification (calibration), the commenter claims, no one can determine
with reasonable certainty whether a non-compliance is due to a test
dummy anomaly or to the vehicle's safety deficiency.
We disagree. The pre-test calibration should adequately address the
suitability of the dummy for testing. We are concerned that the post-
test calibration requirement could handicap and delay our ability to
resolve a potential vehicle or motor vehicle equipment test failure
solely because the post-test dummy might have experienced a component
failure and might no longer conform to all of the specifications. On
several occasions during the past few years, a dummy has been damaged
during a compliance test such that it could not satisfy all of the
post-test calibration requirements. Yet the damage to the dummy at the
time it occurred did not affect the dummy's
[[Page 17186]]
ability to accurately measure the performance requirements of the
standard. We are also concerned that the interaction between the
vehicle or equipment and the dummy could be directly responsible for
the dummy's inability to meet calibration requirements. In such an
instance, the failure of the test dummy should not preclude the agency
from seeking a compliance investigation. Thus, we conclude that a post-
calibration requirement would not be in the public interest, since it
could impede our proceeding with a compliance investigation in those
cases where the test data indicate that the dummy measurements were not
markedly affected by the dummy damage or that some aspect of the
vehicle or its equipment design were responsible for the dummy failure.
TRC also asks that a provision be added to the test procedure to
specify that a light coat of talcum powder is applied to the headform
skin to reduce the tackiness of the urethane. The agency has addressed
the powdering question during the formulation of the Part 572 Subpart B
rulemaking (50th percentile male) and has evaluated its merits in this
rulemaking. We rejected the powdering issue on the basis of
subjectivity of the procedure, which could unnecessarily complicate
compliance tests in which the CRABI 12 dummy is used. Additionally, we
believe that powder is neither needed nor helps to assure consistent
head performance. We found no benefits or advantages in using the
powder. Accordingly, we have not adopted the suggested change.
Instrumentation
The agency proposed generic specifications for all of the dummy-
based sensors, which included--
(1) head, thorax, and pelvis accelerometers designated in drawing
SA572-S4 and shown in drawing 921022-000;
(2) force and/or moment transducers:
(a) pubic load cell SA572-S24,
(b) lumbar spine and neck force moment transducer SA572-S23, and
(c) shoulder load cell SA572-S25.
Comments on proposed generic sensors were received from the
Alliance and Denton. The Alliance supports the intent of the agency in
proposing generic specifications, but finds the specifications not
sufficiently generic. Denton commented on the need to revise
specifications in drawings SA572-S23, -S24, -25, and 921022-35 (pelvis
structure weldment).
Weight Specifications
Denton recommends changing the weights of the specified load cells
in SA572-S23, -S24 and -S25. Denton also believes that several drawings
should indicate a maximum weight, and not a nominal weight. We concur
with this suggestion. While we would prefer to establish nominal
weights for the load cells,\3\ there is no acceptable method of
weighing the load cells, particularly those containing integral cables.
Because of this, weight tolerances for the load cells could not be
established. Until an acceptable weighing procedure is developed, dummy
manufacturers must take into account the variabilities of load cell
weights to assure that each subsystem weight specification, as shown in
sheet 5 of drawing 921022-000, is met. Accordingly, we have specified
in the sensor drawings only maximum weights, as follows:
\3\ Load cell weights with only ``maximum'' weight designations
could vary considerably. While not specifying a minimum load cell
weight may not matter much for larger adult test dummies, lack of
such a specification poses a potentially larger problem for the
smaller child test dummies.
--Drawing SA572-23 (neck and lumbar spine)--0.34 lb maximum (each);
--Drawing SA572-24 (pubic)--0.58 lb maximum; and
--Drawing SA572-25 (shoulder)--0.14 lb maximum.
Denton also suggests that the load cell weight specifications
should clarify that the specified weight does not include any cable or
mounting hardware, except as noted. We disagree with this suggestion.
All of the load cells specified by the agency include weights
associated with 8 in. of cable length.
Accelerometer Specifications
The Alliance supports our intent to propose generic specifications
for sensors to reduce the restrictive nature of instrumentation
specifications seen in the past. However, the commenter believes that
the proposed sensor specifications are not sufficiently generic. The
commenter states that the generic specifications would require the use
of a certain model made by a specific manufacturer, having a particular
seismic mass and mounting hole configuration. The commenter notes that
other accelerometers might be acceptable but can not be used under the
proposed specification. The Alliance suggests that the agency develop a
more functional description.
We are aware of at least two manufacturers that have in the past or
are now marketing accelerometers that match the specifications listed
in the drawings. The specific hole patterns are needed for mounting the
accelerometers in several locations in this dummy as well as all of the
other Part 572 dummies. Although the sensing mass of the accelerometer
is defined relative to its attachment surface, hole patterns and
mounting platform dimensions need to be known to assure the existence
of compatible space, mating surfaces and methods of attachment in the
areas where the accelerometers are to be mounted. In addition, shock
and vibration standards require that matching mounting surfaces and
attachments have structural integrity for vibration control purposes
which we believe are sufficiently defined in the drawing package. While
the Alliance's suggestion that the agency develop a ``more functional
description'' of the sensors is attractive as a concept and warrants
further study, we do not believe that the technology is sufficiently
developed for implementation at the present time.
Pubic Load Cell Mounting
Denton suggests changes to drawing 921022-035 to specify an
orientation of two tapped holes in the pelvic structure weldment to
accommodate the mounting of the pubic load cell SA572-S24. If that is
not done, Denton states, it will not be possible to insert a wrench
through the access holes in the load cell to loosen the set screws
which thread into detail 3 of drawing 921022-035. Denton suggests that
``the top surface of the weldment (which is ground flat to within
0.001) be indicated as datum A, and that a callout be added indicating
that the centerlines of the holes are perpendicular to the datum
surface A within 0.020 inches.''
We agree with the comment and have revised drawing 921022-35 in
line with the suggested changes.
Accelerometer Frequency Response
Denton, in its comments on frequency response for the Hybrid III-
type 5th percentile female adult dummy (Docket No. NHTSA-1998-4283-10),
suggests adding a note on each of the sensor drawings indicating ``* *
*what CFC channel class should be used for recording data with that
type of transducer.'' This is a reasonable suggestion, since the SAE
J211 clearly deals with the entire data channel and not with a
particular sensor within the data channel. Accordingly, a note has been
added to the drawings saying that ``Signal output must be compatible
with and recordable in the data channel defined by SAE J211.''
[[Page 17187]]
Title and Features of the Procedures for Assembly, Disassembly and
Inspection
The preamble for the NPRM on the CRABI 12 dummy notes that the
final rule package will contain a ``User's Manual'' for the dummy. The
manual would contain identified procedures on how to inspect, assemble
and disassemble the dummy, similar to procedures published for other
Part 572 dummies. Responding to this issue, DTES noted that it has
developed a User's Manual for this dummy and suggested its
incorporation into Part 572. There are a number of reasons why we
decline to incorporate the DTES User's Manual as a reference document.
DTES's manual contains, besides inspection and assembly procedures,
several calibration procedures and response requirements. Calibration
procedures and response requirements are set forth by this final rule
in Part 572. It is not advisable to reference a document which could
contain calibration procedures and response requirements that may be
inconsistent or in conflict with the Part 572 requirements. Further,
while the DTES manual appears to be reasonably well developed and well
suited for research use, it has a number of redundancies and
ambiguities which render it less suited for regulation and compliance
testing purposes. Further, the DTES User's Manual is copyrighted by
both the SAE and FTSS, which restrict its use and distribution as a
public document.
Because we concluded that the DTES manual should not be
incorporated into Part 572, we generated and incorporated into Part 572
our own document which is limited to addressing procedures for
inspection, assembly and disassembly of the CRABI 12 test dummy. We
have titled the document Procedures for Assembly, Disassembly and
Inspection (PADI), Subpart R, CRABI 12-month-old Infant Crash Test
Dummy (CRABI-12, Alpha version), March 2000. Our incorporation of the
PADI does not prevent anyone from using the procedures contained in the
DTES User's Manual. However, persons using the DTES document in tests
assuring compliance with our safety standards are responsible for
ensuring that the test dummies they use meet the specifications adopted
today and are suitable for compliance testing.
Nomenclature
The CRABI 12 test dummy is incorporated in Part 572 as Subpart R.
Today's final rule designates the dummy adopted today as the alpha
version. Further significant changes to the dummy will be designated as
beta, gamma, etc., to assure that modifications can be easily tracked
and identified.
Regulatory Analyses and Notices
Executive Order 12866 and DOT Regulatory Policies and Procedures
This rulemaking document was not reviewed by the Office of
Management and Budget under E.O. 12866, ``Regulatory Planning and
Review.'' The rulemaking action is also not considered to be
significant under the Department's Regulatory Policies and Procedures
(44 FR 11034, February 26, 1979).
This document amends 49 CFR Part 572 by adding design and
performance specifications for a new 12-month-old child dummy that we
may later incorporate into Federal motor vehicle safety standards. This
rule indirectly imposes requirements on only those businesses which
choose to manufacture or test with the dummy, in that the agency will
only use dummies for compliance testing that meet all of the criteria
specified in this rule. It may affect vehicle and air bag manufacturers
if it is incorporated by reference into the advanced air bag
rulemaking, and may affect child restraint manufacturers if it is
incorporated into the child restraint system standard.
The cost of an uninstrumented 12-month-old dummy is approximately
$19,000. Instrumentation would add $15,000 to $43,000 to the cost,
depending on the amount of instrumentation the user chooses to add.
Because the economic impacts of this proposal are minimal, no
further regulatory evaluation is necessary.
Executive Order 13132
We have analyzed this rule in accordance with Executive Order 13132
(``Federalism''). We have determined that this rule does not have
sufficient Federalism impacts to warrant the preparation of a
federalism assessment.
Executive Order 13045
Executive Order 13045 (62 FR 19885, April 23, 1997) applies to any
rule that: (1) Is determined to be ``economically significant'' as
defined under E.O. 12866, and (2) concerns an environmental, health or
safety risk that NHTSA has reason to believe may have a
disproportionate effect on children. If the regulatory action meets
both criteria, we must evaluate the environmental health or safety
effects of the planned rule on children, and explain why the planned
regulation is preferable to other potentially effective and reasonably
feasible alternatives considered by us.
This rule is not subject to the Executive Order because it is not
economically significant as defined in E.O. 12866. It also does not
involve decisions based on health risks that disproportionately affect
children.
Executive Order 12778
Pursuant to Executive Order 12778, ``Civil Justice Reform,'' we
have considered whether this rule will have any retroactive effect.
This rule does not have any retroactive effect. A petition for
reconsideration or other administrative proceeding will not be a
prerequisite to an action seeking judicial review of this rule. This
rule does not preempt the states from adopting laws or regulations on
the same subject, except that it does preempt a state regulation that
is in actual conflict with the federal regulation or makes compliance
with the Federal regulation impossible or interferes with the
implementation of the federal statute.
Regulatory Flexibility Act
Pursuant to the Regulatory Flexibility Act (5 U.S.C. 601 et seq.,
as amended by the Small Business Regulatory Enforcement Fairness Act
(SBREFA) of 1996) whenever an agency is required to publish a notice of
rulemaking for any proposed or final rule, it must prepare and make
available for public comment a regulatory flexibility analysis that
describes the effect of the rule on small entities (i.e., small
businesses, small organizations, and small governmental jurisdictions).
However, no regulatory flexibility analysis is required if the head of
an agency certifies the rule will not have a significant economic
impact on a substantial number of small entities. SBREFA amended the
Regulatory Flexibility Act to require Federal agencies to provide a
statement of the factual basis for certifying that a rule will not have
a significant economic impact on a substantial number of small
entities.
I have considered the effects of this rulemaking action under the
Regulatory Flexibility Act (5 U.S.C. Sec. 601 et seq.) and certify that
this rule will not have a significant economic impact on a substantial
number of small entities. The rule does not impose or rescind any
requirements for anyone. The Regulatory Flexibility Act does not,
therefore, require a regulatory flexibility analysis.
National Environmental Policy Act
We have analyzed this amendment for the purposes of the National
Environmental Policy Act and determined that it will not have any
significant impact on the quality of the human environment.
[[Page 17188]]
Paperwork Reduction Act
Under the Paperwork Reduction Act of 1995, a person is not required
to respond to a collection of information by a Federal agency unless
the collection displays a valid OMB control number. This rule does not
have any new information collection requirements.
National Technology Transfer and Advancement Act
Section 12(d) of the National Technology Transfer and Advancement
Act of 1995 (NTTAA), Public Law 104-113, section 12(d) (15 U.S.C. 272)
directs us to use voluntary consensus standards in its regulatory
activities unless doing so would be inconsistent with applicable law or
otherwise impractical. Voluntary consensus standards are technical
standards (e.g., materials specifications, test methods, sampling
procedures, and business practices) that are developed or adopted by
voluntary consensus standards bodies, such as the Society of Automotive
Engineers (SAE). The NTTAA directs us to provide Congress, through OMB,
explanations when we decide not to use available and applicable
voluntary consensus standards.
The CRABI 12 test dummy that is the subject of this document was
developed under the auspices of the SAE. All relevant SAE standards
were reviewed as part of the development process. The following
voluntary consensus standards have been used in developing the dummy:
SAE Recommended Practice J211, Rev. Mar95 ``Instrumentation for Impact
Tests''; and SAE J1733 of 1994-12 ``Sign Convention for Vehicle Crash
Testing.''
Unfunded Mandates Reform Act
Section 202 of the Unfunded Mandates Reform Act of 1995 (UMRA)
requires Federal agencies to prepare a written assessment of the costs,
benefits and other effects of proposed or final rules that include a
Federal mandate likely to result in the expenditure by State, local or
tribal governments, in the aggregate, or by the private sector, of more
than $100 million in any one year (adjusted for inflation with base
year of 1995). Before promulgating a NHTSA rule for which a written
statement is needed, section 205 of the UMRA generally requires us to
identify and consider a reasonable number of regulatory alternatives
and adopt the least costly, most cost-effective or least burdensome
alternative that achieves the objectives of the rule.
This rule does not impose any unfunded mandates under the Unfunded
Mandates Reform Act of 1995. This rule does not meet the definition of
a Federal mandate because it does not impose requirements on anyone.
Further, it will not result in costs of $100 million or more to either
State, local, or tribal governments, in the aggregate, or to the
private sector. Thus, this rule is not subject to the requirements of
sections 202 and 205 of the UMRA.
Regulation Identifier Number (RIN)
The Department of Transportation assigns a regulation identifier
number (RIN) to each regulatory action listed in the Unified Agenda of
Federal Regulations. The Regulatory Information Service Center
publishes the Unified Agenda in April and October of each year. You may
use the RIN contained in the heading at the beginning of this document
to find this action in the Unified Agenda.
List of Subjects in 49 CFR Part 572
Incorporation by reference, Motor vehicle safety.
In consideration of the foregoing, 49 CFR Part 572 is amended as
follows:
PART 572--ANTHROPOMORPHIC TEST DUMMIES
1. The authority citation for Part 572 continues to read as
follows:
Authority: 49 U.S.C. 322, 30111, 30115, 30117 and 30166;
delegation of authority at 49 CFR 1.50.
2. 49 CFR Part 572 is amended by adding a new Subpart R consisting
of 572.150-572.155, to read as follows:
Subpart R--CRABI 12-Month-Old Infant Crash Test Dummy, Alpha Version
Sec.
572.150 Incorporation by reference.
572.151 General description.
572.152 Head assembly and test procedure.
572.153 Neck-headform assembly and test procedure.
572.154 Thorax assembly and test procedure.
572.155 Test condition and instrumentation.
Subpart R--12-Month-Old Infant, Alpha Version
Sec. 572.150 Incorporation by reference.
(a) The following materials are incorporated by reference in this
subpart R.
(1) A drawings and specifications package entitled ``Parts List and
Drawings, Subpart R, CRABI 12-Month-Old Infant Crash Test Dummy,
(CRABI-12, Alpha version), March 2000'' and consisting of :
(i) Drawing No. 921022-001, Head Assembly, incorporated by
reference in Secs. 572.151, 572.152, 572.154, and 572.155;
(ii) Drawing No. 921022-041, Neck Assembly, incorporated by
reference in Secs. 572.151, 572.153, 572.154, and 572.155;
(iii) Drawing No. TE-3200-160, Headform, incorporated by reference
in Secs. 572.151 and 572.153;
(iv) Drawing No. 921022-060, Torso Assembly, incorporated by
reference in Secs. 572.151, 572.154, and 572.155;
(v) Drawing No. 921022-055, Leg Assembly, incorporated by reference
in Secs. 572.151, and 572.155 as part of a complete dummy assembly;
(vi) Drawing No. 921022-054, Arm Assembly, incorporated by
reference in Secs. 572.151, and 572.155 as part of the complete dummy
assembly;
(2) A procedures manual entitled ``Procedures for Assembly,
Disassembly and Inspection (PADI), Subpart R, CRABI 12-month-old Infant
Crash Test Dummy (CRABI-12, Alpha version), March 2000,'' incorporated
by reference in Sec. 572.151;
(3) SAE Recommended Practice J211/1, Rev. Mar95 ``Instrumentation
for Impact Tests--Part 1--Electronic Instrumentation'', incorporated by
reference in Sec. 572.155;
(4) SAE J1733 1994-12 ``Sign Convention for Vehicle Crash
Testing'', incorporated by reference in Sec. 572.155.
(b) The Director of the Federal Register approved those materials
incorporated by reference in accordance with 5 U.S.C. 552(a) and 1 CFR
Part 51. Copies of the materials may be inspected at NHTSA's Docket
Section, 400 Seventh Street S.W., room 5109, Washington, DC, or at the
Office of the Federal Register, 800 North Capitol Street, NW, Suite
700, Washington, DC.
(c) The incorporated materials are available as follows:
(1) The drawings and specifications package referred to in
paragraph (a)(1) of this section and the procedures manual referred to
in paragraph (a)(2) of this section are available from Reprographic
Technologies, 9000 Virginia Manor Road, Beltsville, MD 20705 (301) 419-
5070.
(2) The SAE materials referred to paragraphs (a)(3) and (a)(4) of
this section are available from the Society of Automotive Engineers,
Inc., 400 Commonwealth Drive, Warrendale, PA 15096.
Sec. 572.151 General description.
(a) The 12-month-old-infant crash test dummy is described by
drawings and specifications containing the following materials:
(1) Technical drawings and specifications package 921022-000
[[Page 17189]]
(refer to Sec. 572.150(a)(1)), the titles of which are listed in Table
A of this section;
(2) Procedures for Assembly, Disassembly and Inspection document
(PADI) (refer to Sec. 572.150(a)(2)).
(b) The dummy consists of the component assemblies set out in the
following Table A:
Table A
------------------------------------------------------------------------
Component assembly Drawing number
------------------------------------------------------------------------
Head Assembly............................. 921022-001.
Neck Assembly (complete).................. 921022-041.
Torso Assembly............................ 921022-060.
Leg Assembly.............................. 921022-055 R&L.
Arm Assembly.............................. 921022-054 R&L.
------------------------------------------------------------------------
(c) Adjacent segments of the dummy are joined in a manner such
that, except for contacts existing under static conditions, there is no
contact between metallic elements throughout the range of motion or
under simulated crash impact conditions.
(d) The structural properties of the dummy are such that the dummy
shall conform to this Subpart in every respect before its use in any
test under this chapter.
Sec. 572.152 Head assembly and test procedure.
(a) The head assembly (refer to Sec. 572.150(a)(1)(i)) for this
test consists of the assembly (drawing 921022-001), triaxial mount
block (SA572-80), and 3 accelerometers (drawing SA572-S4).
(b) Frontal and rear impact.
(1) Frontal impact. When the head assembly in paragraph (a) of this
section is dropped from a height of 376.01.0 mm
(14.80.04 in) in accordance with paragraph (c)(3)(i) of
this section, the peak resultant acceleration measured at the head CG
shall not be less than 100 g or more than 120 g. The resultant
acceleration vs. time history curve shall be unimodal, and the
oscillations occurring after the main pulse shall be less than 17
percent of the peak resultant acceleration. The lateral acceleration
shall not exceed 15 g's.
(2) Rear impact. When the head assembly in paragraph (a) of this
section is dropped from a height of 376.01.0 mm
(14.80.04 in) in accordance with paragraph (c)(3)(ii) of
this section, the peak resultant acceleration measured at the head CG
shall be not less than 55 g and not more than 71 g. The resultant
acceleration vs. time history curve shall be unimodal, and the
oscillations occurring after the main pulse shall be less than 17
percent of the peak resultant acceleration. The lateral acceleration
shall not exceed 15 g's.
(c) Head test procedure. The test procedure for the head is as
follows:
(1) Soak the head assembly in a controlled environment at any
temperature between 18.9 and 25.6 deg.C (66 and 78 deg.F) and at any
relative humidity between 10 and 70 percent for at least four hours
prior to a test. These temperature and humidity levels shall be
maintained throughout the entire testing period specified in this
section.
(2) Before the test, clean the impact surface of the head skin and
the steel impact plate surface with isopropyl alcohol, trichlorethane,
or an equivalent. Both impact surfaces shall be clean and dry for
testing.
(3)(i) For a frontal impact test, suspend the head assembly with
its midsagittal plane in vertical orientation as shown in Figure R1 of
this subpart. The lowest point on the forehead is 376.01.0
mm (14.8 0.04 in) from the impact surface. The 3.30 mm
(0.13 in) diameter holes located on either side of the dummy's head are
used to ensure that the head is level with respect to the impact
surface. The angle between the lower surface plane of the neck
transducer mass simulator (drawing 910420-003) and the plane of the
impact surface is 45 1 degrees.
(ii) For a rear impact test, suspend the head assembly with its
midsagittal plane in vertical orientation as shown in Figure R2 of this
subpart. The lowest point on the back of the head is
376.01.0 mm (14.8 0.04 in) from the impact
surface. The 3.30 mm (0.13 in) diameter holes located on either side of
the dummy's head are used to ensure that the head is level with respect
to the impact surface. The angle between the lower surface plane of the
neck transducer structural replacement (drawing 910420-003) and the
impact surface is 90 1 degrees.
(4) Drop the head assembly from the specified height by a means
that ensures a smooth, instant release onto a rigidly supported flat
horizontal steel plate which is 50.8 mm (2 in) thick and 610 mm (24 in)
square. The impact surface shall be clean, dry and have a micro finish
of not less than 203.2 x 10-6 mm (8 micro inches) (RMS)
and not more than 2032.0 x 10-6 mm (80 micro inches)
(RMS).
(5) Allow at least 2 hours between successive tests of the head
assembly at the same impact point. For head impacts on the opposite
side of the head, the 30-minute waiting period specified in
Sec. 572.155(m) does not apply.
Sec. 572.153 Neck-headform assembly and test procedure.
(a) The neck and headform assembly (refer to
Secs. 572.150(a)(1)(ii) and 572.150(a)(1)(iii)) for the purposes of
this test consists of parts shown in CRABI neck test assembly (drawing
TE-3200-100);
(b) When the neck and headform assembly, as defined in
Sec. 572.153(a), is tested according to the test procedure in
Sec. 572.153(c), it shall have the following characteristics:
(1) Flexion.
(i) Plane D referenced in Figure R3 of this subpart shall rotate in
the direction of pre-impact flight with respect to the pendulum's
longitudinal centerline not less than 75 degrees and not more than 86
degrees. Within this specified rotation corridor, the peak positive
moment about the occipital condyles shall be not less than 36 N-m (26.6
ft-lbf) and not more than 45 N-m (33.2 ft-lbf).
(ii) The positive moment about the occipital condyles shall decay
for the first time to 5 N-m (3.7 ft-lbf) between 60 ms and 80 ms after
time zero.
(iii) The moment about the occipital condyles shall be calculated
by the following formula: Moment (N-m) = My - (0.005842m) x (Fx),
where My is the moment about the y-axis, Fx is the shear force measured
by the neck transducer (drawing SA572 -S23) and 0.005842m is the
distance from the point at which the load cell measures the force to
the occipital condyle.
(2) Extension.
(i) Plane D referenced in Figure R4 of this subpart shall rotate in
the direction of preimpact flight with respect to the pendulum's
longitudinal centerline not less than 80 degrees and not more than 92
degrees. Within the specified rotation corridor, the peak negative
moment about the occipital condyles shall be not more than -12 Nm (-8.9
ft-lbf) and not less than -23 N-m (-17.0 ft-lbf) within the minimum and
maximum rotation interval.
(ii) The negative moment about the occipital condyles shall decay
for the first time to -5 Nm (-3.7 lbf-ft) between 76 ms and 90 ms after
time zero.
(iii) The moment about the occipital condyles shall be calculated
by the following formula: Moment (N-m) = My - (0.005842m) x (Fx),
where My is the moment about the y-axis, Fx is the shear force measured
by the neck transducer (drawing SA572 -S23) and 0.005842m is the
distance from the point at which the load cell measures the force to
the occipital condyle.
(c) Test procedure.
[[Page 17190]]
(1) Soak the neck assembly in a controlled environment at any
temperature between 20.6 and 22.2 deg.C (69 and 72 deg.F) and at any
relative humidity between 10 and 70 percent for at least four hours
prior to a test. These temperature and humidity levels shall be
maintained throughout the testing period specified in this section.
(2) Torque the jam nut (drawing 9001336) on the neck cable (drawing
ATD-6206) to 0.2 to 0.3 Nm (2-3 in-lbf).
(3) Mount the neck-headform assembly, defined in paragraph (b) of
this section, on the pendulum so the midsagittal plane of the headform
is vertical and coincides with the plane of motion of the pendulum as
shown in Figure R3 for flexion and Figure R4 for extension tests.
(i) The moment and rotation data channels are defined to be zero
when the longitudinal centerline of the neck and pendulum are parallel.
(ii) The test shall be conducted without inducing any torsion of
the neck.
(4) Release the pendulum and allow it to fall freely to achieve an
impact velocity of 5.2 0.1 m/s (17.1 0.3 ft/s)
for flexion and 2.5 0.1 m/s (8.2 0.3 ft/s) for
extension measured at the center of the pendulum accelerometer at the
instant of contact with the honeycomb.
(i) Time-zero is defined as the time of initial contact between the
pendulum striker plate and the honeycomb material. The pendulum data
channel shall be defined to be zero at this time.
(ii) Stop the pendulum from the initial velocity with an
acceleration vs. time pulse which meets the velocity change as
specified in the following table. Integrate the pendulum acceleration
data channel to obtain the velocity vs. time curve as indicated in
Table B:
Table B.--Pendulum Pulse
----------------------------------------------------------------------------------------------------------------
Time Flexion Time Extension
----------------------------------------------------------------------------------------------------------------
m/s m/s ft/s ms m/s ft/s
----------------------------------------------------------------------------------------------------------------
10.................................. 1.6-2.3 5.2-7.5 6...................... 0.8-1.2 2.6-3.9
20.................................. 3.4-4.2 11.2-13 10..................... 1.5-2.1 4.9-6.9
.8
25.................................. 4.3-5.2 14.1-17 14..................... 2.2-2.9 7.2-9.5
.1
----------------------------------------------------------------------------------------------------------------
Sec. 572.154 Thorax assembly and test procedure.
(a) Thorax Assembly (refer to Sec. 572.150(a)(1)(iv)) . The thorax
consists of the part of the torso assembly shown in drawing 921022-060.
(b) When the thorax of a completely assembled dummy (drawing
921022-000) is impacted by a test probe conforming to Sec. 572.155(a)
at 5.0 0.1m/s (16.5 0.3 ft/s) according to the
test procedure in paragraph (c) of this section, the peak force,
measured by the impact probe in accordance with paragraph
Sec. 572.155(a), shall be not less than 1514 N (340.7 lbf) and not more
than 1796 N (404.1 lbf).
(c) Test procedure.
(1) Soak the dummy in a controlled environment at any temperature
between 20.6 and 22.2 deg.C (69 and 72 deg.F) and at any relative
humidity between 10 and 70 percent for at least four hours prior to a
test. These temperature and humidity levels shall be maintained
throughout the entire testing period specified in this section.
(2) The test dummy is clothed in a cotton-polyester based tight
fitting sweat shirt with long sleeves and ankle long pants whose
combined weight is not more than 0.25 kg (.55 lbs).
(3) Seat and orient the dummy on a level seating surface without
back support as shown in Figure R5 of this subpart, with the lower
limbs extended forward, parallel to the midsagittal plane and the arms
0 to 5 degrees forward of vertical. The dummy's midsagittal plane is
vertical within /1 degree and the posterior surface of the
upper spine box is aligned at 90/1 degrees from the
horizontal. (Shim material may be used under the upper legs to maintain
the dummy's specified spine box surface alignment).
(4) Establish the impact point at the chest midsagittal plane so
that the impact point of the longitudinal centerline of the probe
coincides with the dummy's midsagittal plane, is centered on the torso
196 /2.5 mm (7.7 /0.1 in) vertically from the
plane of the seating surface, and is within 0.5 degrees of a horizontal
plane.
(5) Impact the thorax with the test probe so that at the moment of
contact the probe's longitudinal center line falls within 2 degrees of
a horizontal line in the dummy's midsagittal plane.
(6) Guide the test probe during impact so that there is no
significant lateral, vertical or rotational movement.
Sec. 572.155 Test conditions and instrumentation.
(a) The test probe for thoracic impacts shall be of rigid metallic
construction, concentric in shape, and symmetric about its longitudinal
axis. It shall have a mass of 2.860.02 kg
(6.30.05 lbs) and a minimum mass moment of inertia of 622
kg-cm2 (0.55 lbs-in-sec2) in yaw and pitch about
the CG. Up to 1/3 of the weight of the suspension cables and their
attachments to the impact probe may be included in the calculation of
mass, but such components may not exceed five percent of the total
weight of the test probe. The impacting end of the probe, perpendicular
to and concentric with the longitudinal axis, must be at least 12.7 mm
(0.5 in) thick, and have a flat, continuous, and non-deformable 101.6
0.25 mm (4.000.01 in) diameter face with an
edge radius of 12.70.25 mm (0.50.01 in). The
probe's end opposite to the impact face must have provisions for
mounting of an accelerometer with its sensitive axis collinear with the
longitudinal axis of the probe. No concentric portions of the impact
probe may exceed the diameter of the impact face. The impact probe
shall have a free air resonant frequency of not less than 1000 Hz.
(b) Head accelerometers shall have the dimensions, response
characteristics, and sensitive mass locations specified in drawing
SA572-S4 and be mounted in the head as shown in drawing 921022-000.
(c) The neck force-moment transducer shall have the dimensions,
response characteristics, and sensitive axis locations specified in
drawing SA572-S23 and shall be mounted for testing as shown in drawing
921022-000 and in figures R3 and R4 of this subpart.
(d) The shoulder force transducers shall have the dimensions and
response characteristics specified in drawing SA572-S25 and are allowed
to be mounted as optional instrumentation in place of part No. 921022-
022 in the torso assembly as shown in drawing 921022-000.
(e) The thorax accelerometers shall have the dimensions, response
characteristics, and sensitive mass locations specified in drawing
SA572-S4 and be mounted in the torso
[[Page 17191]]
assembly in triaxial configuration as shown in drawing 921022-000.
(f) The lumbar spine and lower neck force/moment transducer shall
have the dimensions and response characteristics specified in drawing
SA572-S23 and are allowed to be mounted as optional instrumentation in
the torso assembly in place of part No. 910420-003 as shown in drawing
921022-000.
(g) The pelvis accelerometers shall have the dimensions, response
characteristics, and sensitive mass locations specified in drawing
SA572-S4 and are allowed to be mounted as optional instrumentation in
the pelvis in triaxial configuration as shown in drawing 921022-000.
(h) The pubic force transducer shall have the dimensions and
response characteristics specified in drawing SA572-S24 and is allowed
to be mounted as optional instrumentation in place of part No. 921022-
050 in the torso assembly as shown in drawing 921022-000.
(i) The outputs of acceleration and force-sensing devices installed
in the dummy and in the test apparatus specified by this part are
recorded in individual data channels that conform to the requirements
of SAE Recommended Practice J211/1, Rev. Mar95 ``Instrumentation for
Impact Tests--Part 1--Electronic Instrumentation'' (refer to
Sec. 572.150(a)(3)), with channel classes as follows:
(1) Head and headform acceleration--Class 1000.
(2) Neck :
(i) Forces--Class 1000;
(ii) Moments--Class 600;
(iii) Pendulum acceleration--Class 180;
(3) Thorax:
(i) Spine and pendulum accelerations--Class 180;
(ii) Shoulder forces--Class 600;
(4) Lumbar:
(i) Forces--Class 1000;
(ii) Moments --Class 600;
(5) Pelvis:
(i) Accelerations--Class 1000;
(ii) Pubic--Class 1000.
(j) Coordinate signs for instrumentation polarity shall conform to
SAE J1733, 1994-12, ``Sign Convention For Vehicle Crash Testing,
Surface Vehicle Information Report,'' (refer to Sec. 572.150(a)(4)).
(k) The mountings for sensing devices shall have no resonance
frequency within a range of 3 times the frequency range of the
applicable channel class.
(l) Limb joints shall be set at l g, barely restraining the weight
of the limb when it is extended horizontally. The force required to
move a limb segment shall not exceed 2 g throughout the range of limb
motion.
(m) Performance tests of the same component, segment, assembly, or
fully assembled dummy shall be separated in time by period of not less
than 30 minutes unless otherwise noted.
(n) Surfaces of dummy components may not be painted except as
specified in this subpart or in drawings referenced in Sec. 572.150.
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BILLING CODE 4910-59-C
Issued: March 27, 2000.
Rosalyn G. Millman,
Acting Administrator.
[FR Doc. 00-7955 Filed 3-30-00; 8:45 am]
BILLING CODE 4910-59-P