US 12,434,711 B2
Method and related system for estimating the International Roughness Index of a road segment
Lorenzo Alleva, Rome (IT); Alessandro Boldrini, Rome (IT); Manfredi Massimilla, Rome (IT); Vittorio Nicolosi, Rome (IT); and Alberto Nantuono, Rome (IT)
Appl. No. 18/288,398
Filed by Bridgestone Europe NV/SA [BE/BE], Zaventem (BE)
PCT Filed Apr. 26, 2022, PCT No. PCT/EP2022/061044
§ 371(c)(1), (2) Date Oct. 26, 2023,
PCT Pub. No. WO2022/229180, PCT Pub. Date Nov. 3, 2022.
Claims priority of application No. 102021000010496 (IT), filed on Apr. 26, 2021.
Prior Publication US 2024/0208511 A1, Jun. 27, 2024
Int. Cl. B60W 40/02 (2006.01); B60W 40/06 (2012.01); G06F 17/17 (2006.01)
CPC B60W 40/06 (2013.01) [G06F 17/17 (2013.01); B60W 2510/222 (2013.01); B60W 2510/225 (2013.01); B60W 2552/35 (2020.02); B60W 2554/4042 (2020.02)] 20 Claims
OG exemplary drawing
 
1. A method for estimating an International Roughness Index (IRI) of a road or road segment, the method comprising:
in a preliminary stage:
collecting values of vehicle tire damping and stiffness coefficients of one or more tires;
collecting:
first vehicle vertical acceleration values measured on one or more motor vehicles driven at one or more given constant speeds along one or more roads or road segments to which known IRI values or known first road profiles are associated;
first vehicle geo-referencing data associated with the measured first vertical acceleration values; and
first vehicle speed data indicative of the one or more given constant speeds associated with the measured first vertical acceleration values;
determining second road profiles based on the values of vehicle tire damping and stiffness coefficients, the first vehicle geo-referencing data, the first vehicle speed data, and the first vehicle vertical acceleration values;
determining second vehicle vertical acceleration values based on the second road profiles, second vehicle geo-referencing data of the second vertical acceleration values, second vehicle speed data indicative of the one or more given constant speeds associated with the measured first vertical acceleration values, and the values of vehicle tire damping and stiffness coefficients;
determining values of vehicle suspension damping and stiffness coefficients of one or more suspensions of one or more vehicles;
determining first and second root mean square values of the first and second vehicle vertical acceleration values, respectively;
determining, based on the known IRI values or the first road profiles on the second root mean square values of the second vehicle vertical acceleration values, on the second vehicle geo-referencing data and on second vehicle speed data, one or more vehicle transfer functions mathematically relating the second root mean square values of the second vehicle vertical acceleration values and the IRI values at the one or more given constant speeds; and
in an IRI estimation stage:
acquiring third vehicle vertical acceleration values measured on a given motor vehicle driven at a driving speed on a given road or road segment, third vehicle geo-referencing data associated with the third vehicle vertical acceleration values, and third vehicle speed data indicative of the given driving speed of the motor vehicle;
computing third root mean square values of the third vehicle vertical acceleration values; and
estimating an IRI value of the given road or road segment based on one or more vehicle transfer functions determined in the preliminary stage and on the third root mean square values of the third vehicle vertical acceleration values and the associated third vehicle geo-referencing data and the third vehicle speed data.