CHAPTER VUpper legform to frontal protection system leading edge
1.Test purpose
1.1.To test compliance with the requirements laid down in paragraph 3.1.3 of Annex I to Directive 2005/66/EC.
2.Test points
2.1.A minimum of three tests must be carried out to the frontal protection system leading edge reference line, at points judged by the test authority to be the most likely to cause injury. Tests shall be to different types of structure where they vary throughout the area to be assessed. The points tested by the test authorities must be indicated in the test report.
3.Test apparatus
3.1.The impactor must comply with the requirements laid down in Section 5 of Chapter IV and with Figure 9.
3.2.When impacting the upper leading edge reference line the impactor mass shall depend upon the general shape of the frontal protection system and must be determined in accordance with Section 4.
3.3.Two load transducers must be fitted to individually measure the forces applied at either end of the impactor, plus strain gauges to measure the bending moments at the centre of the impactor and at positions 50 mm either side of the centre line. (see Figure 9)
3.4.The instrumentation response value CFC, as defined in ISO 6487:2000, must be 180 for all transducers. The CAC response values, as defined in ISO 6487:2000, must be 10 kN for the force transducers and 1000 Nm for the bending moment measurements.
3.5.The impactor must 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 must 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.
3.6.The impactor must be mounted and propelled as specified in Chapter II.
4.Test procedure
4.1.The stabilised temperature of the test apparatus and the vehicle or sub-system must be 20° ± 4 °C.
4.2.The tests must be made to the frontal protection system between the corners of the frontal protection system upper leading edge, to points selected under paragraph 2.1.
4.3.The impactor must be aligned in such a way that the centre line of the propulsion system and the longitudinal axis of the impacting impactor are parallel to the longitudinal axis of the frontal protection system as mounted on the vehicle or test frame. The tolerances to these directions are ± 2 °. At the time of first contact the impactor centre line must be coincident with the selected impact position with a ± 10 mm tolerance (see Figure 10), and laterally with a tolerance of ± 10 mm.
4.4.The required impact velocity, the angle of impact and the impactor mass must be determined in accordance with paragraphs 4.5 and 4.6. The tolerance on the impact velocity is ± 2 % and the tolerance on the impact direction is ± 2 °. The effect of gravity must be taken before the time of first contact. The 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, in accordance with paragraph 4.7.1.
4.5.The required impact velocity and the angle of impact are determined from Figures 11 and 12 with reference to the vertical height of the intended impact position on the frontal protection system leading edge reference line and the frontal protection system lead.
4.6.The required impact energy must be derived from Figure 13 with reference to the vertical height, from ground reference level, of the intended impact position on the frontal protection system leading edge and the frontal protection system lead.
4.7.
The total mass of the impactor includes those propulsion and guidance components which are effectively part of the impactor during the impact, including the extra weights.
4.7.1.The required value of the impactor mass must be calculated in the following way:
M | = 2E/V2 |
Where | E = Required Impact Energy (J)
V = Required Velocity (m/s)
|
4.7.2.The 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 required impactor kinetic energy.
4.7.3.The required extra weights must be fitted accordingly in order to give the calculated value of impactor mass, calculated in accordance with paragraph 4.7.1, to the rear of the rear member as shown in Figure 9, or to components of the guidance system which are effectively part of the impactor during the impact.
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