Technical Bulletin

Euro NCAP Mobile Progressive
Deformable Barrier Face
Specification
Draft Version 1.2.1

March 2023
TB 022

TitleVersionDocument NumberAuthor
Date
Related Documents
StatusApplication Date

Euro NCAP MPDB Specification
v1.2.1
TB 022J Ellway
3rd March 2023
MPDB testing protocol
Information
January 2023

Copyright ©Euro NCAP 2023 - This work is the intellectual property of Euro NCAP. Permission is granted for thismaterial to be shared for non-commercial, educational purposes, provided that this copyright statement appears on
the reproduced materials and notice is given that the copying is by permission of Euro NCAP. To disseminate otherwise
or to republish requires written permission from Euro NCAP.

Preface
In 2020 the European New Car Assessment Programme (Euro NCAP) will be updating its
offset frontal impact test procedure. These updates will be centred on the adoption of theThor anthropometric test device and a new barrier face for the mobile progressive deformablebarrier (MPDB). This Technical Bulletin details the specification for the honeycomb barrier
face.
Euro NCAP tests may only be performed using MPDB faces from approved suppliers. The
suppliers approved for use are detailed in Euro NCAP Technical Bulletin TB 029.

DISCLAIMER: Euro NCAP has taken all reasonable care to ensure that the information
published in this document is accurate and reflects the technical decisions taken by theorganisation. In the unlikely event that this protocol contains a typographical error or any
other inaccuracy, Euro NCAP reserves the right to make corrections and determine theassessment and subsequent result of the affected requirement(s).

EUROPEAN NEW CAR ASSESSMENT PROGRAMME (Euro NCAP)

Table of Contents
1.

CHARACTERISTICS OF THE PROGRESSIVE DEFORMABLE BARRIER ....................... 6

2.

DESIGN OF THE IMPACTOR ............................................................................................... 11

3.

CONFORMITY OF PRODUCTION ....................................................................................... 14

4.

STATIC TESTS ........................................................................................................................ 16

5.

DYNAMIC TUBULAR IMPACTOR TEST PROCEDURE ................................................... 17

1.

CHARACTERISTICS OF THE PROGRESSIVE DEFORMABLE
BARRIERThe impactor consists of three stacked aluminium honeycomb blocks. The front and rear blocks
offer constant levels of force with deflection, the middle block has been processed to give a
progressively increasing level of force with increasing deflection. The rear block is bonded toan aluminium back plate which is also used for mounting the impactor. The three blocks arebonded to three aluminium sheets and the entire impactor is covered by an aluminium skin(cladding) riveted to the front face.
1.1

Honeycomb blocks

1.1.1

Geometric characteristics

1.1.1.1

The impactor consists of three layers of honeycomb blocks as shown in Figure 1.
The principal dimensions of all blocks are 1000 ± 2.5mm x 568 ± 5.0mm, see Figure
2. The 1000mm is in the W direction and the 568mm is in the L direction as shownin Figure 3.

1.1.1.2

The three honeycomb blocks are stacked; the rear block (A) is 90 ± 1.0mm deep, themiddle (B) block is 450 ± 1.0mm deep and the front block (C) is 250 ± 1.0mm deep.

1.1.2

Pre-crush

1.1.2.1

No part of the honeycomb is to be pre crushed.

1.1.3

Material characteristics

1.1.3.1

The expansion direction of the Aluminium Honeycomb shall be in the W direction
as defined in Figure 3.

1.1.3.2

The cell dimension for the rear block shall be 6.3mm ± 10 per cent, the middle block
shall be 9.5mm ± 10 per cent, the front block shall be 19.1mm ± 10 per cent, see
Figure 4.

1.1.3.3

All honeycomb blocks must be made of 3003 aluminium.

1.1.3.4

The aluminium honeycomb blocks (A, B, C) shall be processed so that the force
deflection-curve when statically crushed is within the specification and corridors inSection 4.

1.1.3.5

The processed honeycomb material used in the honeycomb blocks to be used forconstruction of the barrier shall be cleaned in order to remove any residue that mayhave been produced during the processing of the raw honeycomb material.

Version 1.2.1
March 2023

6

1.2

Back plate

1.2.1

Geometric characteristics

1.2.1.1

The geometric characteristics of the back plate (1) shall be in accordance with Figure
1, Figure 2 and Figure 5.

1.2.1.2

The upper flange shall be vertical and the lower flange shall be bent through 90
degrees towards the rear.

1.2.1.3

The two 30mm side flanges shall be bent through 90 degrees towards thehoneycomb.

1.2.2

Material characteristics

1.2.2.1

The back plate shall be manufactured from aluminium of series AlMg2 to AlMg3
with hardness between 50 and 67 HBS. The back plate shall have a thickness of 3.0± 0.2mm.

1.3

Intermediate plates

1.3.1

Geometric characteristics

1.3.1.1

The geometric characteristics of the two intermediate plates (2) shall be inaccordance with Figure 1 and Figure 2.

1.3.2

Material characteristics

1.3.2.1

The intermediate plates are manufactured from 5754 H111 aluminium. Theintermediate plates shall have a thickness of 0.5 ± 0.06mm.

1.4

Contact plate

1.4.1

Geometric characteristics

1.4.1.1

The geometric characteristics of the contact plate (3) shall be in accordance withFigure 1 and Figure 2.

1.4.1.2

Twenty 6.2mm holes shall be drilled through the contact plate to accommodate blindrivets.

1.4.2

Material characteristics

1.4.2.1

The contact plate is manufactured from 1050A H24 aluminium. The contact plate
shall have a thickness of 1.5 ± 0.1mm.

1.5

Cladding

1.5.1

Geometric characteristics

1.5.1.1

The geometric characteristics of the cladding (4) shall be in accordance with Figure
1 and Figure 2.

Version 1.2.1
March 2023

71.5.1.2

The upper flange is 75mm high, the lower flange is 53mm high before bending. The
upper flange shall be vertical and the lower flange shall be bent through 90 degrees
towards the rear.

1.5.1.3

Twenty 6.2mm holes shall be drilled through the front cladding face to accommodate
blind rivets.

1.5.2

Material characteristics

1.5.2.1

The cladding plate is manufactured from 5754 H22 aluminium. The cladding plate
shall have a thickness of 0.8 ± 0.1mm.

1.5.3

Rivets

1.5.3.1

Twenty 6mm diameter aluminium or steel blind rivets shall be used to connect thecontact and cladding plates.

1.6

Location of the honeycomb blocks

1.6.1

The honeycomb blocks shall be aligned with each other and centred on the backplate.

1.7

Bonding

1.7.1

Adhesive shall be applied to the surfaces as illustrated in Figure 1. The adhesive to
be used throughout should be a two-part polyurethane, (such as Ciba Geigy
XB5090/1 resin with XB5304 hardener) or equivalent.

1.7.2

The adhesive should be applied to one surface only. In cases where honeycomb is tobe bonded to aluminium sheet, the adhesive should be applied to the aluminium sheet
only. A maximum of 0.5kg/m2 shall be applied evenly over the surface, giving amaximum film thickness of 0.5mm. See Figure 1.

1.7.3

Care should be taken to ensure that adhesive does not run into the honeycomb cells,causing an increase in crush strength of the honeycomb core.

1.7.4

For the back plate, the minimum bonding strength shall be 0.6MPa (87psi), tested
according to Section 1.7.6.

1.7.5

At the bent flange connection between the cladding sheet and backplate, adhesive
tape may be used in this area only to prevent bonding material from dripping during
construction. No specification for this tape is given as its presence does not influence
the barrier performance.

Version 1.2.1
March 2023

8

1.7.6

Bonding strength tests

1.7.7

Flatwise tensile testing is used to measure bond strength of adhesives according toASTM C297-61.

1.7.8

The test piece should be 100mm x 100mm, and 15mm deep, bonded to a sample ofthe back plate material. The honeycomb used should be representative of that in theimpactor, i.e. chemically etched to an equivalent degree as that near to the rearmost
intermediate plate (2) in the barrier but without pre-crushing.

1.8

Construction

1.8.1

The main honeycomb blocks shall be bonded to the sheets with adhesive such thatthe cell axes are perpendicular to the sheets.

1.8.2

The outer cladding shall be bonded to the contact plate. The upper and lower surfacesof the outer cladding sheet shall not be bonded to the honeycomb blocks but should
be positioned closely to it. The cladding sheet shall be adhesively bonded to the backplate at the mounting flanges.

1.8.3

Holes for mounting the barrier are to be drilled in the mounting flanges and thedimensions are as shown in Figure 5.

1.8.4

Five holes shall be drilled in the top flange and five in the bottom flange. The holes
in the upper flange only may be opened for ease of attachment provided sufficient
grip can be developed to avoid detachment during the whole impact test.

1.8.5

The flange holes shall be drilled to ± 1mm of the nominal distances as defined inFigure 5.

1.9

Impactor attachment

1.9.1

The attachment of the barrier face shall be such that the vehicle shall not contact any
part of the structure more than 75mm from the top surface of the barrier (excludingthe upper flange) during any stage of the impact.

1.9.2

When mounted to the trolley, the barrier backplate shall be flat, with no bends, sothat there are no gaps greater than 3mm between the barrier backplate and the trolley
mounting face.

1.9.3

The deformable barrier shall be fixed by means of 10 bolts, five in the top mounting
flange and five in the bottom. These bolts shall be of at least 8mm diameter.

1.9.4

Steel clamping strips shall be used along the entire length of both the top and bottom
mounting flanges. These strips shall be 60mm high and 1000mm wide and have athickness of at least 3mm.

1.9.5

The edges of the clamping strips shall be rounded-off to prevent tearing of the barrier
against the strip during impact. The edge of the strip shall be located no more than
5mm above the base of the upper barrier-mounting flange, or 5mm below the top of
the lower barrier-mounting flange.

Version 1.2.1
March 2023

91.9.6

Five clearance holes of 9.5mm diameter must be drilled in both strips to correspondwith those in the mounting flange on the barrier. The mounting strip and barrier
flange holes may be widened from 9.5mm up to a maximum of 25mm in order toaccommodate differences in back-plate arrangements.

1.9.7

In order to accommodate the radius of the lower mounting flange, the lower edge ofthe trolley mounting face shall be chamfered at 45 degrees.

1.9.8

None of the fixtures shall fail in the impact test, both the upper and lower mounting
flanges must remain attached to the trolley.

Version 1.2.1
March 2023

102.

DESIGN OF THE IMPACTOR

All dimensions are in mm.
2.1

Barrier face

2.1.1

The tolerances on the dimensions of the blocks allow for the difficulties of measuring
cut aluminium honeycomb. The tolerance on the overall dimension of the impactor
is less than that for the individual blocks since the honeycomb blocks can beadjusted, with overlap if necessary, to maintain a more closely defined impact facedimension.
The MPDB is composed of the following components:(1) One back plate(2) Two intermediate plates(3) One contact plate(4) One outer cladding(5) Blind rivets(6) Adhesive(A) One rear deformable honeycomb core(B) One progressively deformable
honeycomb core(C) One front deformable honeycomb core

Figure 1: Exploded isometric view of MPDB

Version 1.2.1
March 2023

11

Figure 2: MPDB dimensions

Figure 3: Aluminium Honeycomb Orientation

Version 1.2.1
March 2023

12

Note: All dimension in mm and +/- 10%
Figure 4: Dimension of Aluminium Honeycomb Cells

Figure 5: Top and bottom mounting flanges

Version 1.2.1
March 2023

13

3.

CONFORMITY OF PRODUCTION

3.1

The barrier manufacturer shall be responsible for the conformity of production
procedures and for that purpose must in particular:

3.1.1

Ensure the existence of effective procedures so that the quality of the products canbe inspected.

3.1.2

Have access to the testing equipment needed to inspect the conformity of eachproduct.

3.1.3

Ensure that the test results are recorded and that the documents remain available fora time period of 10 years after testing.

3.1.4

Demonstrate that the samples tested are a reliable measure of the performance of thebatch (examples of sampling methods according to batch production are givenbelow).

3.1.5

Analyse results of tests in order to verify and ensure the stability of the barrier
characteristics, making allowance for variations of an industrial production, such astemperature, raw materials quality, time of immersion in chemical, chemical
concentration, neutralisation etc, and the control of the processed material in orderto remove any residue from the processing.

3.1.6

Ensure that any set of samples or test pieces giving evidence of non-conformity gives
rise to a further sampling and test. All the necessary steps must be taken to restore
conformity of the corresponding production.

3.2

The manufacturer's level of certification must be at least ISO 9001-2015 standard.

3.3

Minimum conditions for the control of production: the holder of an agreement will
ensure the control of conformity following the methods hereunder described.

3.4

Examples of sampling according to batch

3.4.1

If several examples of one block type are constructed from one original block ofaluminium honeycomb and are all treated in the same treatment bath (parallelproduction), one of these examples could be chosen as the sample and care is taken
to ensure that the treatment is evenly applied to all blocks. If not, it may be necessary
to select more than one sample.

3.4.2

If a limited number of similar blocks (say three to twenty) are treated in the samebath (serial production), then the first and last block treated in a batch, all of which
are constructed from the same original block of aluminium honeycomb, should betaken as representative samples. If the first sample complies with the requirements
but the last does not, it may be necessary to take further samples from earlier in theproduction until a sample that does comply is found. Only the blocks between thesesamples should be considered to be approved.

3.4.3

Once experience is gained with the consistency of production control, it may bepossible to combine both sampling approaches, so that more than one groups of

Version 1.2.1
March 2023

14

parallel production can be considered to be a batch provided samples from the firstand last production groups comply.
3.5

Traceability

3.5.1

Barriers shall carry consecutive serial numbers which are stamped, etched orotherwise permanently attached, from which the batches for the individual blocks
and the date of manufacture can be established.

Version 1.2.1
March 2023

15

4.

STATIC TESTS

4.1

Static testing will be performed on all honeycomb blocks and follow the procedure
detailed in this section.

4.2

Blocks A and C

4.2.1

The aluminium honeycomb for the homogeneous block A shall be processed so thatthe strength is 1.540MPa to 1.711MPa when statically crushed in accordance withthe procedure defined in NHTSA TP-214D.

4.2.2

The aluminium honeycomb for the homogeneous block C shall be processed so thatthe strength is 0.308MPa to 0.342MPa when statically crushed in accordance withthe procedure defined in NHTSA TP-214D.

4.3

Block B

4.3.1

One or more samples (according to the batch method) taken from each batch ofprocessed honeycomb core shall be tested, according to the following test procedure:

4.3.2

The test samples shall be 250mm x 250mm x 450mm.

4.3.3

The samples should be compressed between two parallel loading plates which are atleast 20mm larger that the block cross section;

4.3.4

The compression speed shall be 100 millimetres per minute, with a tolerance of
5 per cent;

4.3.5

The data acquisition for static compression shall be sampled at a minimum of 5Hz.

4.3.6

The static test shall be continued until the block compression reaches 355mm.

4.3.7

The crush strength characteristic for block B shall lie within the corridors in Figure
6.

AB
CD

Crush
0.756MPa
1.090MPa0.616MPa0.950MPa

Deflection
6mm
350mm
6mm
350mm

Figure 6: Block B Static Corridor
Version 1.2.1
March 2023

16

5.

DYNAMIC TUBULAR IMPACTOR TEST PROCEDURE

5.1

Characteristics of the mobile barrier.

5.1.1

The total mass shall be 1300kg +/- 20kg. The trolley shall be constructed so that nopermanent deformation appears after the test. It shall be guided during the impact
phase limiting the deviation to no more than 5° and 2° in the vertical and horizontal
planes respectively.

5.1.2

The front and rear track width of the trolley shall be 1500 ± 10mm.

5.1.3

The wheelbase of the trolley shall be 3000 ± 10mm.

5.1.4

The centre of gravity shall be situated in the longitudinal median vertical planewithin 10mm, 1000 ± 30mm behind the front axle and 500 ± 30mm above theground.

5.1.5

The distance between the front face of the impactor and the centre of gravity of thebarrier shall be 2290 ± 30mm.

5.1.6

Measurements to be made on the trolley. The position of the transducers measuring
the deceleration of the Centre of Gravity (COG) of the trolley during the impact shallbe parallel to the longitudinal axis of the trolley (CFC of 180).

5.1.7

The trolley displacement is obtained by integration of the deceleration curve of theCOG of the trolley. The global crush force is obtained by the multiplication of thetrolley acceleration in CFC of 60 by its mass.

5.2

Deformable barrier face to be tested.

5.2.1

The deformable barrier to be tested shall be representative of the series productionof the barrier.

5.2.2

The deformable barrier shall be firmly attached to the rigid wall in such a way thatno relative displacement occurs during the test. It is acceptable for the lower
mounting flange to be unbent for the purpose of this test.

5.3

Tubular impactor design

5.3.1

The impactor consists of a tubular structure as defined in Figure 7. The material of
the tubular impactor must be in steel and the geometry of the impactor must be inaccordance with the dimensions described. Additional strengthening and bracing
may be added provided that they are in the longitudinal direction and do not alter theloading applied to the barrier.

5.3.2

The tubular impactor shall be firmly attached to the trolley in such a way that norelative displacement occurs during the test.

5.4

Test configuration

Version 1.2.1
March 2023

17

5.4.1The velocity of the trolley at the moment of impact shall be 60km/h -0/+1km/h. If
the test was performed at a higher impact speed and the test results meet therequirements, the test shall be considered satisfactory.

5.4.2

The angle between the longitudinal axis of the rigid wall and the direction of motionof the trolley shall be 0° ± 2°.

5.4.3

The tubular impactor shall overlap the right side of the barrier face by 800 +/- 20mm
in Y axis. See Figure 8.

5.5

Validation

5.5.1

The force deflection curves of the deformable barrier tested shall lie within the force
corridors defined in Figure 9.

Figure 7: Tubular impactor design

Version 1.2.1
March 2023

18

Figure 8: Impact alignment

ABCDEFForce
200kN300kN
550kN
100kN
200kN
450kN

Deflection
50mm
200mm
500mm
70mm
200mm
500mm

Figure 9: Tubular impactor corridors

Version 1.2.1
March 2023

19