LT1: Development, calibration and validation of bus following modelPresentation Transcript
LT1: Development, calibration and validation of bus-following model to support analysis and evaluation of alternative BRT strategies under different scenarios Luis Antonio Lindau Paula Manoela dos Santos
Mile- OUTPUTSstones M1 Do vehicle-following literature review M2 Check potential of existing models to represent bus behavior M3 Select data collection technique M4 Plan field data collection M5 Collect data M6 Process data M7 Define bus-following model M8 Final report Transit Leaders Roundtable MIT, June 2011
Comparing: GHR and Gipps GHR reveled unstable for typical Gipps is attractive for successive bus stopping maneuvers. stopping buses. 1 0,6 0,5 0,4 0 0,2acceleration (m/s²) 0 20 40 60 80 100 120 140 acceleration (m/s²)) -0,5 0 0 50 100 150 200 -1 -0,2 -1,5 -0,4 -2 -0,6 -2,5 time (s) -0,8 time (s)
Data collection (manual vs. automatic) Reported last year
Solution: image recognition software Kinovea 0.8.15 • Developed for studying athletic techniques • free and open source • 33 info/s
Paralaxis correction 𝐶1 +𝐶2 𝑋 𝑓 +𝐶3 𝑌 𝑓 𝐶6 +𝐶7 𝑋 𝑓 +𝐶8 𝑌 𝑓 𝑋𝑟 = 𝐶4 𝑋 𝑓 +𝐶5 𝑌 𝑓 +1 𝑌𝑟 = 𝐶4 𝑋 𝑓 +𝐶5 𝑌 𝑓 +1Bleyl, R. L. (1972) Traffic analysis of time lapse photographs without employing a perspective grid. TrafficEngineering, p. 29-31.
Methodology Find a setting to film Locate and measure 4 reference pointsFilm making (with vehicle loading Film analysis with image recognition estimation) softwareData collection (distance vs. time) Calibration of parameters