Development of a Diagnostic System for Air Brakes in Trucks

The purpose of this Innovations Deserving Exploratory Analysis (IDEA) project was to enhance the safety of trucks by developing diagnostic systems that assess the health of brake systems. Brake systems in trucks are crucial for ensuring the safety of vehicles and passengers on the roadways. Most trucks in the U.S. are equipped with S-cam air brake systems and they are sensitive to maintenance. Moreover, any incident involving trucks results in material damage, which can have serious environmental and economic repercussions, and sometimes, the loss of life, which cannot be measured in economic terms. This project consisted of three stages. In the first stage, the authors developed leak detection algorithms based on a mathematical model that predicts the evolution of the pressure in the brake chambers, without leak, in response to the brake pedal input. The second stage included the estimation of push rod stroke in the absence of a leak. The third stage included the development, experimental implementation, testing and evaluation of the prototype diagnostic system in the presence of leaks. Tests of the prototype diagnostic system conducted on the test bench at Texas A&M University indicated that the prototype diagnostic system accurately predicts the "severity" of the leak (characterized by the "effective area" of the cross-section of the leak) and reasonably predicts the pushrod stroke in the presence of leaks. The underlying algorithms required the development and corroboration of a mathematical model for pressure transients in the presence of a leak. The model used orifice equations for describing the mass flow rate of air leaking and incorporated the balance of mass equation. Experiments indicate that the resulting mathematical model successfully predicts brake pressure.

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  • Authors:
    • Dharba, Swaroop
    • Rajagopal, K R
  • Publication Date: 2008-8


  • English

Media Info

  • Media Type: Web
  • Edition: Final Report
  • Features: Figures; Photos; References; Tables;
  • Pagination: 39p
  • Serial:
  • Publication flags:

    Open Access (libre)

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Filing Info

  • Accession Number: 01149287
  • Record Type: Publication
  • Report/Paper Numbers: Safety IDEA Project 12
  • Files: TRIS, TRB
  • Created Date: Jan 28 2010 4:34PM