This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Effects of Altitude and Road Gradients in Boosted Hydraulic Brake Systems
Technical Paper
2016-01-0463
ISSN: 0148-7191, e-ISSN: 2688-3627
Annotation ability available
Sector:
Language:
English
Abstract
Brake systems are strongly related with safety of vehicles. Therefore a reliable design of the brake system is critical as vehicles operate in a wide range of environmental conditions, fulfilling different security requirements. Particularly, countries with mountainous geography expose vehicles to aggressive variations in altitude and road grade. These variations affect the performance of the brake system. In order to study how these changes affect the brake system, two approaches were considered. The first approach was centered on the development of an analytical model for the longitudinal dynamics of the vehicle during braking maneuvers. This model was developed at system-level, considering the whole vehicle. This allowed the understanding of the relation between the braking force and the altitude and road grade, for different fixed deceleration requirement scenarios. The second approach was focused on the characterization of the vacuum servo operation. This characterization was developed at component-level. An experimental methodology was used for the characterization of the vacuum servo operation under different atmospheric pressure conditions. A relation between the mechanical gain of the vacuum servo and the altitude was found when considering the relation between atmospheric air pressure and altitude. A complete model was obtained by merging the two approaches. As a case study, a given vehicle was considered, taking into account its specific parameters. A mechanical gain for the complete brake system was found. The braking performance of the vehicle as a function of altitude and road grade was assessed.
Recommended Content
Authors
Citation
Sierra, J., Cruz, C., Munoz, L., Avila, S. et al., "Effects of Altitude and Road Gradients in Boosted Hydraulic Brake Systems," SAE Technical Paper 2016-01-0463, 2016, https://doi.org/10.4271/2016-01-0463.Also In
References
- U.S. Department of Transportation Standard No. 135 - Light Vehicle Brake Systems - Passenger Cars, Multipurpose Passenger Vehicles, Trucks and Buses Federal Motor Vehicle Safety Standards 1998
- Australian Government Australian Design Rule 35/00 -Commercial Vehicle Brake Systems Australian Design Rules for Vehicles as made 2006
- United Nations Economic Commision For Europe Regulation No. 13. Uniform Provisions Concerning the Approval of Vehicles of Categories M, N and O With Regard to Braking UN Vehicle Regulations - 1958 Agreement 2008
- Standardization Administration of China GB 12676-2014 Technical requirements and testing methods for commercial vehicle and trailer braking systems 2014
- Olsson , G. , Mateyka , J. , and Innes , J. Brake System Safety Analysis SAE Technical Paper 710593 1971 10.4271/710593
- Parker , G. , Keranen , T. , and Cardon , M. Determining the Effects of Brake Degradation SAE Technical Paper 730190 1973 10.4271/730190
- Travaglia , C. , Araujo , J. , Bochi , M. , Yoneda , A. et al. Analysis of Drum Brake System with Computational Methods SAE Technical Paper 2013-36-0022 2013 10.4271/2013-36-0022
- Zhang , L. , Ruan , C. , and Meng , D. The Influence of Vacuum Booster Design Parameters on Brake Pedal Feel SAE Int. J. Passeng. Cars - Mech. Syst. 7 4 1311 1320 2014 10.4271/2014-01-2499
- Salazar I. Economical Geographt of the East Andean Region (In spanish) Cartagena, Bank of the Republic of Colombia 2010
- Day A. J. Braking of Road Vehicles Oxford Elsevier 2014
- Budynas R. G. Shigley's mechanical engineering design Singapore McGraw-Hill 2008
- Gillespie , T. Fundamentals of Vehicle Dynamics Warrendale Society of Automotive Engineers, Inc. 1992
- Digital Dutch 1976 Standard Atmosphere Calculator 1 3 2015 http://www.digitaldutch.com/atmoscalc/index.htm
- Sierra J. , Muñoz L. Effect of the altitude and the road grade over the acceleration performance of a vehicle CIMM 2015 Cartagena, Colombia 2015
- National Aeronautics and Space Administration, (NASA) U.S Standard Atmosphere 1976
- White F. Fluid Mechanics New York McGraw-Hill 2011
- Guiggiani M. The Science of Vehicle Dynamics Pisa Springer 2013
- Bill , K. and Breuer , J. Brake Technology Handbook Warrendale SAE International 2008 978-0-7680-1787-8
- Ministerio de Comercio Industria y Turismo de Colombia, Resolution Number 4983: Technical Regulation aplicable to brake systems or their components for usage on road vehicles and trailers, that are imported or manufactured to be used or commercialized in Colombia (In spanish) 2011