Measurement of the International Roughness Index (IRI) Using an Autonomous Robot (P3-AT)

In this paper, we test whether an autonomous robot can be used to measure the International Roughness Index (IRI), a description of pavement ride quality in terms of its longitudinal profile. A ready-made robot, the Pioneer P3-AT, was equipped with odometers, a laptop computer, CCD laser, and a SICK laser ranger finder to autonomously perform the collection of longitudinal profiles. ProVAL (Profile Viewing and AnaLysis) software was used to compute the IRI. The preliminary test was conducted indoors on an extremely smooth and uniform 50 m length of pavement. The average IRI (1.09 m/km) found using the P3AT is robustly comparable to that of the commercial ARRB walking profilometer. This work is an initial step toward autonomous robotic pavement inspections. We also discuss the future integration of inertial navigation systems and global positioning systems (INS and GPS) in conjunction with the P3-AT for practical pavement inspections.