Development of an Operationally Efficient PTC Braking Enforcement Algorithm for Freight Trains

Software algorithms used in positive train control (PTC) systems designed to predict freight train stopping distance and enforce a penalty brake application have been shown to be overly conservative, which can lead to operational inefficiencies by interfering with normal train operations. Federal Railroad Administration contracted Transportation Technology Center, Inc. to investigate approaches to improve these algorithms and to reduce the associated operational inefficiencies. As part of this program, several new approaches to PTC enforcement were introduced and were shown, through simulations and field testing, to improve the operational efficiency of the algorithm. An appropriate safety objective for these algorithms was established from a fault-tree analysis of the accidents PTC was conceived to prevent. A standard methodology was also established by which any PTC enforcement algorithm can be evaluated against design safety and performance measures. This methodology involves a statistical evaluation of the algorithm by means of a Monte Carlo simulation process, as well as limited, focused field testing, which provides more confidence in the safety and performance of the software at less cost than traditional field testing methods. This methodology was then used to evaluate PTC supplier algorithms that incorporate concepts introduced in this project.

• Record URL:
  http://www.fra.dot.gov/eLib/details/L04712
• 
• Availability:
  • Find a library where document is available. Order URL: www.fra.dot.gov
• Supplemental Notes:
  • Appendices F available online at https://www.fra.dot.gov/Elib/Document/3328 Appendices G-L available online at https://www.fra.dot.gov/Elib/Document/3329
• Corporate Authors:

  Transportation Technology Center, Incorporated

  55500 DOT Road
  Pueblo, CO  United States  81001

  Federal Railroad Administration

  Office of Railroad Policy and Development, 1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Brosseau, Joe
  • Ede, Bill Moore
  • Pate, Shad
  • Wiley, R B
  • Drapa, Joe
• Publication Date: 2013-8

Language

• English

Media Info

• Media Type: Digital/other
• Features: Appendices; Figures; References; Tables;
• Pagination: 314p

Subject/Index Terms

• TRT Terms: Adaptive control; Algorithms; Braking; Emergency brakes; Freight trains; Monte Carlo method; Positive train control; Simulation
• Subject Areas: Freight Transportation; Railroads; Safety and Human Factors; Vehicles and Equipment; I91: Vehicle Design and Safety;

Filing Info

• Accession Number: 01491745
• Record Type: Publication
• Report/Paper Numbers: DOT/FRA/ORD-13/34, Funding number: DTFR53-00-C-00012, Task Order 242
• Files: TRIS, USDOT
• Created Date: Sep 3 2013 12:28PM