PSI - Issue 38

Denis Chojnacki et al. / Procedia Structural Integrity 38 (2022) 362–371 Author name / Structural Integrity Procedia 00 (2021) 000 – 000

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instrumentation, see Fig. 10. To better control our road types while being robust to the specificities of each target region, we created a road quality acquisition and characterization technique to be used in our instrumented cars. 3.4. Road characterization through 8hVDV The original requirement inside PSA in 2010 was to be able to balance different Quality in Use tests schedule on different PG (Brazil, France, Russia … ) and to get the same level of solicitation in 3 directions corresponding to a desired customer severity Level without very costly RLDA campaign. Therefore, dedicated post-processing methodologies has been developed inside Stellantis Groupe and some patented based on these few channels. One Example 8hVDV parameter below with runs qualification. Principle : A record system with 3D accelerometer and GPS is installed at the center of gravity of the car

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Fig. 10. (a) Record system with 3D accelerometer and GPS, (b) System installed at Center of Gravity.

With this system, we can produce some deliverables based on (ISO2631 standard) as: = (∫ 4 ( ). 0 ) 1/4 with a run of duration under acceleration ( ) in X direction We can also produce a global VDV VDV Global = VDV xyz = (VDV x 4 + VDV y 4 + VDV z 4 ) 0.25 (2) And finally we can express 8h_VDV to be independent of the duration of the run. _ _ ( ) = ( ∗ ∗ ) . (3) This value can also be determined for small time window observation in order to be able to make scale Road Quality Classification with _ ( ) , see Fig. 11 a b

Fig. 11. (a) Road Quality Categorization; (b) Quality Road categorization coupled with GPS