Curving simulation and stability of a creep-controlled wheelset for high speed rail-vehicles

Higher travel speeds of rail vehicles will be possible by developing sophisticated top performance bogies having creep-controlled wheelsets. In this case the torque transmission between the right and the left wheel is realized by an actively controlled creep coupling. To investigate hunting stability and curving capability the linear equations of motion are written in state space notation. Simulation results are obtained with realistic system parameters from industry and various controller gains. The advantage of the „creep-controlled wheelset" is discussed by comparison the simulation results with the dynamic behaviour of the special cases „solid-axle wheelset" and „loose wheelset" (independent rotation of the wheels). The stability is also investigated with a root-locus analysis.

Impact assessment of the Virginia Railway Express Commuter Rail on land use development patterns in northern Virginia.

Federal Transit Administration, Washington, D.C.

An investigation of truck size and weight limits - technical supplement. Volume 3: truck and rail fuel effects of truck size and weight limits.

Transportation Department, Office of the Assistant Secretary for Policy and International Affairs, Washington, D.C.

Annotated bibliography of rail transit safety, 1975-1980, with emphasis on safety research and development. Final report.

Urban Mass Transportation Administration, Washington, D.C.

Evaluation of retroreflective markings to increase rail car conspicuity -- safety of highway-railroad grade crossings.

Transportation Systems Center, Cambridge, Mass.

Rail safety/ equipment crashworthiness. Volume IV: Executive summary. Interim report.

Federal Railroad Administration, Office of Research and Development, Washington, D.C.

Rail safety/ equipment crashworthiness. Volume II: Design guide. Interim report.

Federal Railroad Administration, Office of Research and Development, Washington, D.C.

Rail safety/ equipment crashworthiness. Volume III: Proposed engineering standards. Interim report.

Federal Railroad Administration, Office of Research and Development, Washington, D.C.

Rail safety/ equipment crashworthiness. Volume I: A systems analysis of injury minimization in rail systems. Interim report.

Federal Railroad Administration, Office of Research and Development, Washington, D.C.

Evaluation of rail rapid transit and express bus service in the urban commuter market. Final report.

Transportation Department, Office of Transportation Planning Analysis, Washington, D.C.

Testing of fibre composite leaf spring for heavy axle loads

This paper presents the results of quasi-static and dynamic testing of glass fiber-reinforced polyester leaf suspension for rail freight vehicles named Euroleaf. The principal elements of the suspension's design and manufacturing process are initially summarized. Comparison between quasi-static tests and finite element predictions are then presented. The Euroleaf suspension have been mounted on a tipper wagon and tested dynamically at tare and full load on a purpose-built shaker rig. A shaker rig dynamic testing methodology has been pioneered for rail vehicles, which follows closely road vehicle suspension dynamic testing methodology. The use and evaluation of this methodology have demonstrated that the Euroleaf suspension is dynamically much softer than steel suspensions even though it is statically much stiffer. As a consequence, the suspension dynamic loading at laden loading conditions is reduced compared to the most advanced steel leaf suspension over shaker rig track tests.

Whole-body vibration exposure study in U.S. railroad locomotives--an ergonomic risk assessment

Whole-body vibration exposure of locomotive engineers and the vibration attenuation of seats in 22 U.S. locomotives (built between 1959 and 2000) was studied during normal revenue service and following international measurement guidelines. Triaxial vibration measurements (duration mean 155 min, range 84-383 min) on the seat and on the floor were compared. In addition to the basic vibration evaluation (aw rms), the vector sum (av), the maximum transient vibration value (MTVV/aw), the vibration dose value (VDV/(aw T1/4)), and the vibration seat effective transmissibility factor (SEAT) were calculated. The power spectral densities are also reported. The mean basic vibration level (aw rms) was for the fore-aft axis x = 0.18 m/sec2, the lateral axis y = 0.28 m/sec2, and the vertical axis z = 0.32 m/sec2. The mean vector sum was 0.59 m/sec2 (range 0.27 to 1.44). The crest factors were generally at or above 9 in the horizontal and vertical axis. The mean MTVV/aw was 5.3 (x), 5.1 (y), and 4.8 (z), and the VDV/(aw T1/4) values ranged from 1.32 to 2.3 (x-axis), 1.33 to 1.7 (y-axis), and 1.38 to 1.86 (z-axis), generally indicating high levels of shocks. The mean seat transmissibility factor (SEAT) was 1.4 (x) and 1.2 (y) and 1 (z), demonstrating a general ineffectiveness of any of the seat suspension systems. In conclusion, these data indicate that locomotive rides are characterized by relatively high shock content (acceleration peaks) of the vibration signal in all directions. Locomotive vertical and lateral vibrations are similar, which appears to be characteristic for rail vehicles compared with many road/off-road vehicles. Tested locomotive cab seats currently in use (new or old) appear inadequate to reduce potentially harmful vibration and shocks transmitted to the seated operator, and older seats particularly lack basic ergonomic features regarding adjustability and postural support.

Crashworthiness analysis of the UMTA state-of-the-art cars. Final report.

Transportation Systems Center, Cambridge, Mass.

Application of active and passive suspension techniques to improve high speed ground vehicle performance - phase II. Final report.

Transportation Department, Office of University Research, Washington, D.C.

Freight transportation petroleum conservation - viability evaluation. Final report.

Mode of access: Internet.