Research On Pavement Roughness Estimation Method Based On Kalman Filter Algorithm

Pavement roughness is one of the most important indexes to evaluate pavement qualit y.Good road roughness is an important guarantee for ride comfort and safet y and the normal service life of vehicles.At present,the testing methods of road roughness are mainl y divided into three categories,namel y,cross-section,response and subjective evaluation method.Among them,the cross-section testing method has high accuracy,but it has the shortcomings of low test efficiency and high cost of purchasing and maintenance of some test equipment;reactive testing method is relativel y convenient to operate,but its stabilit y is poor,and standardized vehicle configuration and testing s ystem are also needed;subjective evaluation testing methods have strong subjectivit y,and there are great differences in the evaluation given b y different evaluators.Therefore,a low-cost and operable road surface testing method is needed.At the same time,it is best to calculate the profile elevation of the pavement profile and the international pavement roughness index.Therefore,a method of using vehicle acceleration response to estimate pavement profile elevation and international roughness index is studied in this paper.The main research contents are as follows:(1)A method for identifying the ph ysical parameters of a 7-degree-offreedom vehicle model is studied.A 7-degree-of-freedom vehicle model is established,and the relationship between vehicle ph ysical parameters and acceleration response power spectrum is derived,which is used to identify the ph ysical parameters of the vehicle model.When the vehicle passes through the speed reducer with a known shape at a certain speed,the power spectrum is obtained by the acceleration response of the vehicle,and the genetic algorithm is used to identify the physical parameters of the vehicle.The simulation of the method is completed,and the results show that the method has high accuracy and good anti-noise performance.(2)Using Kalman filter algorithm,the profile elevation of road surface is calculated according to the vehicle acceleration response data.The d ynamic equation of the forced vibration of the 7-degree-of-freedom vehicle model is established,and the pavement profile elevation is calculated according to the vehicle acceleration response data b y using the discrete Kalman filter algorithm based on unknown input.The simulation of the method is completed,and the results show that the method has high accuracy.(3)The verification test of the theoretical calculation method of pavement roughness is carried out.Firstl y,the ph ysical parameters of the vehicle model corresponding to the test vehicle are identified b y power spectrum method,and the identified parameters are verified.Then the road roughness test is carried out,and the international roughness index IR I calculated according to the acceleration data is compared with the IR I output of the laser roughness meter.The test results show that when the road condition of the road section to be tested is good,the average relative error of most of the calculation results is less than 20% with high accuracy,which verifies the effectiveness of the IRI calculation method based on Kalman filter algorithm in this paper.The IRI calculated from the acceleration data can be used to evaluate the road roughness.