An Enhanced Simulation Capability For Studying The Braking Steering And Ride Of Commercial Vehicles

Author : Matthew Leonard Shurtz
Publisher :
ISBN 13 :
Total Pages : 394 pages
Book Rating : 4.:/5 (712 download)

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Download or read book Effects of ABS Controller Parameters on Heavy Truck Model Braking Performance written by Matthew Leonard Shurtz and published by . This book was released on 2006 with total page 394 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: The National Highway Traffic Safety Administration (NHTSA) aims to keep America's roadways safe for vehicle operators, passengers, and pedestrians; a key component to this mission is the element of crash avoidance. Because so many injury related accidents involve heavy trucks, that sector is of significant concern. Most heavy truck braking accidents result from a failure to control under extreme braking maneuvers. One component which has aided this problem is the implementation of anti-lock braking systems (ABS) into these vehicles. In order to study the ABS braking behavior of these vehicles, models were created to accurately simulate their braking behaviors, by using the vehicle dynamics software package TruckSim along with Simulink, which was used to create brake and ABS controller models. These models were run in parallel to create a full vehicle simulation. A model of a 6x4 Peterbilt straight truck was completed in 2004, which used this same modeling scheme. An ABS controller model was developed that accurately mimicked the behavior of the Peterbilt's ABS system, verified through experimental data. This model was upgraded in this study to include better modeling of brake treadle and chamber pressures and also to include the capability of modeling other ABS configurations. The previous ABS model simulated a 6s6m system, in which the wheel speeds of all six wheels were monitored and the brakes of each wheel could be modulated independently. Through modifications to the model in this study, 4s4m and 4s3m ABS configurations can now be studied. The new Peterbilt model was then verified by comparison to experimental data, and was found to accurately model the response of the Peterbilt for each ABS configuration. The ABS controller model was then manipulated to be used for the simulation of a tractor-trailer combination vehicle. Again, TruckSim models were created for a 4x2 Sterling tractor and a 48 ft, 2-axle van trailer. Also, an individual ABS controller model was created for each by matching the simulated response of the vehicle to experimentally determined results. In addition, the ABS controller model of the trailer included the capability of simulating 4s4m, 4s2m, and 2slm ABS systems. Through this process, a tractor-trailer model was completed so that the effects of various ABS controller parameters and ABS configurations could be studied for the vehicle. A total of five different ABS systems were created for the trailer model. The first of those was a 2s 1 m system, which was created to simulate an experimentally studied trailer ABS system. This 2slm system was then used to create a 4s2m and a 4s4m system that had the exact same controller parameters. Two additional 2slm systems were created, one of which was designed to perform poorly in straight-ahead braking situations and the other was designed to perform poorly in brake-in-curve situations. More details of these models will be given later in this report. Straight-ahead braking and brake-in-curve simulations were conducted to study the longitudinal and lateral effectiveness of the tractor-trailer equipped with these five different ABS systems. It was found that upgrading to a 4s2m or 4s4m ABS system resulted in no discernable difference in longitudinal braking performance. Also, it was shown that a very aggressive trailer ABS system (allows a very low amount of slip to develop in the tires) will perform poorly in longitudinal braking situations but will perform very well in lateral tests. The opposite is true for an ABS system that is very lax, in that the controller allows a great deal of wheel slip (approaching lock-up). Finally, it was discovered that the optimum ABS controller system for lateral braking performance will include select-low logic.