A STATE-CONSTRAINED APPROACH TO VEHICLE-FOLLOWER CONTROL FOR SHORT-HEADWAY AGT SYSTEMS

Vehicle-following in an automated-guideway transit (AGT) system is a longitudinal control scheme where the state of a given vehicle is determined by the behavior of the preceding vehicle. The study represents the initial phase of an investigation that is to be continued in order to determine the feasibility of implementing a state-constrained vehicle-following controller into a real system. The report documents an investigation into the automatic longitudinal control of vehicles using a vehicle-follower strategy in the short-headway range operation (0.5 to 3 s). The study states that at short time headways a kinematic constraint on vehicle operation arises as a consequence of the velocity, acceleration, and jerk limits imposed to assure passenger comfort. This constraint requires a trailing vehicle to maintain a spacing such that it may react to nominal preceding-vehicle maneuvers without collisions and without exceeding service jerk and acceleration limits. A nonlinear feedback controller is designed to force the vehicle to follow the kinematically required spacing until the desired headway is attained. The design is based on a technique that uses an optimal feedback control with state constraints. Several suboptimal controls with reduced informational requirements are also presented, thus producing an easily instrumentable controller that properly responds to all possible nominal maneuvers of a preceding vehicle. This report concludes that the technique presented has shown to admit a workable solution to the vehicle-following problem at short headways.

• Supplemental Notes:
  • See also report dated Jul 75, PB-255 953.
• Corporate Authors:

  Johns Hopkins University, Baltimore

  Baltimore, MD  United States  21218

  Urban Mass Transportation Administration

  400 7th Street, SW
  Washington, DC  United States  20590
• Authors:
  • Pue, A J
• Publication Date: 1977-8

Media Info

• Pagination: 123 p.

Subject/Index Terms

• TRT Terms: Automatic control; Automation; Electronic control; Feedback control; Kinematics; Optimization; Safety; Spacing; Speed control; Traffic control; Urban transportation; Vehicles
• Subject Areas: Operations and Traffic Management; Public Transportation; Safety and Human Factors; Vehicles and Equipment;

Filing Info

• Accession Number: 00167288
• Record Type: Publication
• Source Agency: National Technical Information Service
• Report/Paper Numbers: UMTA-MD-06-0022-77-2
• Contract Numbers: DOT-UT-60042T
• Files: NTIS, TRIS, USDOT
• Created Date: Nov 23 2002 12:00AM