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Braking has a strong effect on a vehicle's front suspension loads when the vehicle is driven over a pothole. The suspension loads of a vehicle braking while going over a pothole are also affected by vehicle design, vehicle weight and speed. In this study a simplified suspension model is presented, which is then validated by the simulation of a vehicle model. The simplified suspension model provides an efficient approach to evaluate effects of braking on wheel rebound into potholes, which determines the magnitude of impact loads when the tires hit the pothole edge. The vehicle model is used not only to validate the simplified suspension model, but also to provide the information of wheel center loads in addition to the wheel position and velocity. The analysis using the vehicle model agrees with pothole test results. The study reveals how vehicle braking affects the wheel center longitudinal forces during the pothole impact.

The SAE Brake Linings Committee launched an evaluation of the current SAE standard J840 “Test Procedures for Brake Shoe and Lining Bonds,” specifically the bond plane shear test. The aim of the study was to identify what settings in the shear test lead to the most repeatable results for a variety of linings. An initial four factor two-level design of experiments (DOE) was conducted, with 15 pads sheared for each condition. The DOE looked at pad material type (NAO and semi-metallic), backing plate attachment type (integrally molded and mechanical retention system), ram offset position (1.0 mm and 4.0 mm) and normal pressure (0 and 0.5 N/mm2). The test measured shear force and percentage material retention for each pad tested. The objective of the DOE was to guide revision of the SAE J840 shear test procedure. For example, the application of a normal force raises the nominal value of the shear force by 30-50%, and reduces the variability of the test results.