Non-Inertial Road Longitudinal Profiler Based On Laser Line Sensor

Due to the installation of a vertical accelerometer,it is recognized that existing inertial laser profilers are influenced by the driving speed seriously.Therefore,it is unable to use inertial profilers to detect roughness on urban roads at a low speed or variable speed.This paper proposes to solve the speed problem from the source and develop a noninertial roughness profiler for road roughness measurement.Based on the project Road Integrated Inspection System,the exterior and interior design requirements of the inspection vehicle are clearly proposed.And the vehicle has been modified successfully.With the help of the latest technologies used in road detection,this paper proposes a new profiler different from traditional inertial profilers.The profiler is composed of a data acquisition module,a trigger module,an orientation module and a power supply module.The data acquisition module consisting of a line laser sensor and a three-dimensional camera can acquire highprecision,high-frequency elevation data.With the help of the data acquisition module,successive longitudinal profiles with overlapping intervals can be acquired.Processing the overlapping intervals with moving reference algorithm can effectively remove longitudinal and vertical deviations which used to be eliminated by the vertical accelerometer.In addition,filters are used to process data and IRI can be calculated with the quarter-car model.Based on the characteristics of the profiler,the software design points are put forward in terms of user and system requirements.The software interface and function are briefly introduced.The performance evaluation scheme of non-inertial roughness profiler is proposed.After completion of the varying speed roughness profiler,a calibration test for the device is given.Elevation measurement accuracy and distance measurement accuracy are verified.Repeatability of the profiler has been certificated at a low,medium and high speed.Results show that repeatability of the profiler is pretty good with a stable output of IRI.In addition,the correlation between this profiler and rod-and-level is tested.The deviation between them is small,and the correlation of device is preliminarily verified.Finally,the noninertial roughness profiler is used to collect road roughness data normally,and a brief introduction of the application of non-inertial profiler has been made.