Roads and Bridges Central Laboratory University of Versailles 09 Décembre 2003 Roads and Bridges Central Laboratory University of Versailles Road Profiles Inputs to Evaluate Loads on the Wheels H. Imine Y. Delanne N.K. M’sirdi 04/12/2018

Summary Introduction Reconstruction methods Vehicle modelling 09 Décembre 2003 Summary Introduction Reconstruction methods Vehicle modelling Observation and estimation of the Road profile Experimental results Conclusion

Proposition Road profile measure Develop an easily implemented method 09 Décembre 2003 Road profile measure Topographic measure (Rule...) GM Profilometer (inertial reference) - Difficulty implementation - Impossibility to build up a 3D profile Road high wave not estimated Impossibility to build up a 3D profile Proposition Develop an easily implemented method Based on non linear observers Take into account a vehicle dynamic model

Vehicle road interaction 09 Décembre 2003 Introduction Road Profile Road Construction Vehicle road interaction Qualify serviceability of road pavement inputs of the vehicle simulator (vehicle wheels positions) many profiles  road surface

Reconstruction Methods Longitudinal Profile Analyser (APL) 09 Décembre 2003 APL measure Laser Accelerometer Reconstruction by Longitudinal Profile Analyser (APL) Reconstruction by Inertial Method (GMR)

This measurement is made by an angular displacement transducer associated with the pendulum; the induced electrical signal is amplified and recorded.

Inertial Method Profile = Z – U 09 Décembre 2003 sensor Accelero-laser front APL Rear 2.92m 1.93m 0.50m Profile = Z – U

Profile : APL and inertial method 09 Décembre 2003 distance Z distance U Profile : APL and inertial method

Position of the plates on the track 09 Décembre 2003 Plate on the track Position of the plates on the track environ 200m 39 m 10 mm 8 mm 1 m Plate 1 Plate 2

Reconstruction of the two plates 09 Décembre 2003 Reconstruction of the two plates Plates

PSD: inertial Method (blue) and APL (red) 09 Décembre 2003 PSD: inertial Method (blue) and APL (red) LPA measure Estimated PO: low wave, MO: average wave, GO: high wave

09 Décembre 2003 Vehicle modelling X Z Y θ φ

Sliding Mode Observer System (S) displacements of the wheels 09 Décembre 2003 Sliding Mode Observer System (S) displacements of the wheels displacement of the vehicle body roll, pitch and yaw angle

Principle of estimation 09 Décembre 2003 Principle of estimation u: unknown input Y: output Model Y u Estimator Observer : estimated road profile : observed state

09 Décembre 2003 System

09 Décembre 2003 Observer

convergence in finite time 09 Décembre 2003 Convergence analysis convergence in finite time

09 Décembre 2003 Experimental results

Displacements and velocities 09 Décembre 2003 Displacements and velocities

Estimated profile and APL measure Estimation of the plates 09 Décembre 2003 Estimated profile and APL measure Estimation of the plates

Estimation of the road normal forces 09 Décembre 2003 Estimation of the road normal forces K B M F e u Sensor y1 y2 Kri, kfi spring stiffness Bri, Bfi damping coefficients

09 Décembre 2003 Road normal force

09 Décembre 2003 Conclusion Results related to the estimation of the road profile by APL and Inertial method are given. Sliding mode observers method constitutes a reliable and easily implemented method to estimate the road profile. Road normal forces can be computed if the road profile under the wheel track is known and applied.

In our future work: Comparison with Walking Profilometer. 09 Décembre 2003 In our future work: Comparison with Walking Profilometer. On-line estimation of the road profile. Extend the approach to a 3D road profile (Road surface)