Commission Decision of 23 December 2003 on the technical prescriptions for the implementation of Article 3 of Directive 2003/102/EC of the European Parliament and of the Council relating to the protection of pedestrians and other vulnerable road users before and in the event of a collision with a motor vehicle and amending Directive 70/156/EEC (notified under document number C(2003) 5041) (Text with EEA relevance) (2004/90/EC)

CHAPTER IV U.K. Upper legform to bonnet leading edge tests

1. Scope U.K.

This test procedure is applicable to requirements under both Section 3.1 and Section 3.2 of Annex I of the Directive 2003/102/EC.

2. General U.K.

2.1. The upper legform impactor for the bonnet leading edge test shall be mounted to the propulsion system, by a torque limiting joint, to prevent large off centre loads damaging the guidance system. The guidance system shall be fitted with low friction guides, insensitive to off-axis loading, that allow the impactor to move only in the specified direction of impact, when in contact with the vehicle. The guides shall prevent motion in other directions including rotation about any axis. U.K.

2.2. The impactor may be propelled by an air, spring or hydraulic gun, or by other means that can be shown to give the same result. U.K.

3. Specification of the test U.K.

3.1. The purpose of the test is to ensure that the requirements given in points 3.1.3 and 3.2.3 of Annex I of the Directive 2003/102/EC are fulfilled. U.K.

3.2. A minimum of three upper legform to bonnet leading edge tests shall be carried out, one each to the middle and the outer thirds of the bonnet leading edge at positions judged to be the most likely to cause injury. However, the test point in each third shall be selected such that the required kinetic energy of impact, determined in point 3.4.2.7, exceeds 200 J, if such a point is available. Tests shall be to different types of structure, where they vary throughout the area to be assessed. The selected test points shall be a minimum of 150 mm apart, and a minimum of 75 mm inside the defined corner reference points. These minimum distances are to be set with a flexible tape held tautly along the outer surface of the vehicle. The positions tested by the laboratories shall be indicated in the test report. U.K.

3.3. All standard equipment fitted to the front end of the vehicle shall be in position. U.K.

3.4. Test method U.K.

3.4.1. Test apparatus U.K.

3.4.1.1. The upper legform impactor shall be rigid, foam covered at the impact side, and 350 ± 5 mm long and comply with Section 4 of this Chapter and Figure 4b of this Part. U.K.

3.4.1.2. The upper legform impactor mass shall be dependent upon the general shape of the front of the car and determined as specified in point 3.4.2.7. U.K.

3.4.1.3. Two load transducers shall be fitted to measure individually the forces applied at either end of the upper legform impactor, plus strain gauges measuring bending moments at the centre of the upper legform impactor and at positions 50 mm either side of the centre line, see Figure 4b. U.K.

3.4.1.4. The instrumentation response value CFC, as defined in ISO 6487:2000, shall be 180 for all transducers. The CAC response values, as defined in ISO 6487:2000, shall be 10 kN for the force transducers and 1 000 Nm for the bending moment measurements. U.K.

3.4.1.5. The upper legform impactor shall meet the performance requirements specified in Section 3 of Appendix I, and shall be fitted with foam cut from the sheet of material used for the dynamic certification test. The certified impactor may be used for a maximum of 20 impacts before re-certification (this limit does not apply to propulsion or guidance components). The impactor shall also be re-certified if more than one year has elapsed since the previous certification or if any impactor transducer output, in any impact, has exceeded the specified CAC. U.K.

3.4.1.6. The upper legform impactor shall be mounted and propelled as specified in paragraphs 2.1 and 2.2. U.K.

3.4.2. Test procedure U.K.

3.4.2.1. The state of the vehicle or subsystem shall comply with the requirements of Chapter I of this Part. The stabilised temperature of the test apparatus and the vehicle or sub-system shall be 20 °C ± 4 °C. U.K.

3.4.2.2. Tests shall be made to the bonnet leading edge, between the ‘corner reference points’ to locations defined in point 3.2. U.K.

3.4.2.3. The upper legform impactor shall be aligned such that the centre line of the propulsion system and the longitudinal axis of the impacting upper legform impactor are in the fore and aft vertical plane of the section of the vehicle to be tested. The tolerances to these directions are ± 2°. At the time of first contact the impactor centre line shall be coincident with the bonnet leading edge reference line with a ± 10 mm tolerance (see Figure 5), and laterally with the selected impact location with a tolerance of ± 10 mm. U.K.

3.4.2.4. The required impact velocity, the direction of impact and the upper legform impactor mass shall be determined as specified in points 3.4.2.6 and 3.4.2.7. The tolerance to the impact velocity is ± 2 % and the tolerance to the impact direction is ± 2°. The effect of gravity shall be taken into account when the impact velocity is obtained from measurements taken before the time of first contact. The upper legform impactor mass should be measured to an accuracy of better than ± 1 %, and if the measured value differs from the required value then the required velocity should be adjusted to compensate, as specified in point 3.4.2.7. U.K.

3.4.2.5. Determination of vehicle shape: U.K.

3.4.2.5.1. The position of the upper bumper reference line shall be determined as defined in point 2.5.1 of Part I. U.K.

3.4.2.5.2. The bonnet leading edge reference line shall be determined as defined in point 2.9.2 of Part I. U.K.

3.4.2.5.3. For the section of bonnet leading edge to be tested the bonnet leading edge height and the bumper lead shall be determined as defined in points 2.9.3 and 2.6 of Part I. U.K.

3.4.2.6. The required impact velocity and the direction of impact shall be determined from Figures 6 and 7 with reference to the values of bonnet leading edge height and bumper lead determined in point 3.4.2.5. U.K.

3.4.2.7. The total mass of the upper legform impactor includes those propulsion and guidance components which are effectively part of the impactor during the impact, including the extra weights. U.K.

Calculate the value of the upper legform impactor mass from:

where

M

=

Mass [kg]

E

=

Impact Energy [J]

V

=

Velocity [m/s].

The required velocity shall be the value derived in point 3.4.2.6 and the energy shall be derived from Figure 8 with reference to the values of bonnet leading edge height and bumper lead determined in point 3.4.2.5.

The upper legform impactor mass may be adjusted from the calculated value by up to ± 10 %, provided the required impact velocity is also changed using the above formula to maintain the same impactor kinetic energy.

3.4.2.8. Fit the required extra weights to give the calculated value of upper legform impactor mass, determined in point 3.4.2.7, to the rear of the rear member as shown in Figure 4b, or to components of the guidance system which are effectively part of the impactor during the impact. U.K.

4. Upper legform impactor U.K.

4.1. The total mass of the front member and other components in front of the load transducer assemblies, together with those parts of the load transducer assemblies in front of the active elements, but excluding the foam and skin, shall be 1,95 ± 0,05 kg. U.K.

4.2. The foam shall be two sheets of 25 mm thick Confor™ foam type CF-45. The skin shall be a 1,5 mm thick fibre reinforced rubber sheet. The foam and rubber skin together shall weigh 0,6 ± 0,1 kg (this excludes any reinforcement, mountings, etc. which are used to attach the rear edges of the rubber skin to the rear member). The foam and rubber skin shall be folded back towards the rear, with the rubber skin attached via spacers to the rear member so that the sides of the rubber skin are held parallel. The foam shall be of such a size and shape that an adequate gap is maintained between the foam and components behind the front member, to avoid significant load paths between the foam and these components. U.K.

4.3. The front member shall be strain gauged to measure bending moments in three positions, as shown in Figure 4b, each using a separate channel. The strain gauges are located on the impactor on the back of the front member. The two outer strain gauges are located 50 ± 1 mm from the impactor's symmetrical axis. The middle strain gauge is located on the symmetrical axis with a ± 1 mm tolerance. U.K.

4.4. The torque limiting joint shall be set so that the longitudinal axis of the front member is perpendicular to the axis of the guidance system, with a tolerance of ± 2°, with the joint friction torque set to a minimum of 650 Nm. U.K.

4.5. The centre of gravity of those parts of the impactor which are effectively forward of the torque limiting joint, including any weights fitted, shall lie on the longitudinal centre line of the impactor, with a tolerance of ± 10 mm. U.K.

4.6. The length between the load transducer centrelines shall be 310 ± 1 mm and the front member diameter shall be 50 ± 1 mm. U.K.

Figure 4b

Upper legform impactor

Figure 5

Upper legform to bonnet leading edge tests

Figure 6

Velocity of upper legform to bonnet leading edge tests with respect to vehicle shape

Notes: U.K.

1. Interpolate horizontally between curves. U.K.

2. With configurations below 20 km/h — test at 20 km/h. U.K.

3. With configurations above 40 km/h — test at 40 km/h. U.K.

4. With negative bumper leads — test as for zero bumper lead. U.K.

5. With bumper leads above 400 mm — test as for 400 mm. U.K.

Figure 7

Angle of upper legform to bonnet leading edge tests with respect to vehicle shape

Notes U.K.

1. Interpolate vertically between curves. U.K.

2. With negative bumper leads — test as for zero bumper lead. U.K.

3. With bumper leads above 150 mm — test as for 150 mm. U.K.

4. With bonnet leading edge heights above 1 050 mm — test as for 1 050 mm. U.K.

Figure 8

Kinetic energy of upper legform to bonnet leading edge tests with respect to vehicle shape

Notes U.K.

1. Interpolate vertically between curves. U.K.

2. With bumper leads below 50 mm — test as for 50 mm. U.K.

3. With bumper leads above 350 mm — test as for 350 mm. U.K.

4. With bonnet leading edge heights above 1 050 mm — test as for 1 050 mm. U.K.

5. With a required kinetic energy above 700 J — test at 700 J. U.K.

6. With a required kinetic energy equal to or below 200 J — no test is required. U.K.