Moving from Exception- to Performance-based
Track Geometry Monitoring Systems
(continued)
System upgrades onboard the FRA's T2000
car are expected to improve GPS accuracy from 10 meters to 2 - 3 meters. "We're
looking into NDGPS with accuracy in the 10- to 15-centimeter range," Clouse
said. (The geometry cars also use a dead-reckoning system in tunnels
or other environments in which
GPS signal transmission is inhibited.)
The FRA's T16 car incorporates an Automated Track Data Alignment System, which
aligns data from previous runs to identify locations where the track is degrading,
even when no exceptions are detected. The use of a simplified Vehicle/Track Interaction
model can be used to help identify derailment-prone track conditions and compare
track geometry to car characteristics. The capability to measure runoff and twist
over 31 feet will be added to the T16 and T2000 this year. With upgrades to the
GPS system, ATIP also plans to incorporate grade measurement with accuracy of
0.1% over 100 feet, he said.
Future Benefits
Working with ENSCO, Inc., the FRA has developed a Digital Track Notebook
(DTN) that provides FRA track inspectors with an electronic exception reporting
system. The second-generation DTN will enable inspectors to:
• Cite and record routine and ATIP inspections
• Relocate verified track defects
• Enter and store freehand notes
• Transcribe track notes via voice recognition software
• Digitally photograph track conditions
• Wirelessly print and send railroad reports on site
• Upload or download information directly from the database
• Utilize reference libraries (Track Compliance Manual, TSS, railroad timetables)
