This paper reviews road surface measurement methods and focusses on high-speed surface inspection using Machine Vision (MV) systems used to detect pavement defects. The Laser Road Surface Tester (Laser RST) is a laser-based, computer-automated non-contact profilometer system with the ability to collect and simultaneously process data about the underlying road surface at 90/km h (Arnberg et al., in press-a). The first Laser RST was built in Sweden in 1981 and is now used to measure roads in Sweden and in 14 other countries throughout the world. In order to improve the crack measurement performance of the Laser RST van, OPQ Systems AB is currently developing a high-speed video data acquisition and analysis (PAVUE) system to be used along side the laser system. However, the addition of the PAVUE system cannot constrain the current laser system in any way, so must be able to acquire and fully process video data at road survey speeds of up to 90 km/h. Such high data rates require unique cameras, lighting, and processing approaches, along with specialized processing hardware architecture. PAVUE is a hardware and software system for the high-speed inspection of surfaces, in particular, road pavement surfaces. The final PAVUE design will be capable of sustained real-time continous inspection of surfaces at velocities of up to 90 km/h. A highly parallel processing system, it will use pipelined processing hardware and one-pass scanline-based processing algorithms. (A)
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