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Institute for Complex Systems Simulation The importance of interactions in determining service measures for bicycles Chris Osowski chris.osowski@soton.ac.uk www.osowski.co.uk Institute for Complex Systems Science, University of Southampton Ben Waterson b.j.waterson@soton.ac.uk Transportation Research Group, University of Southampton Slide 2 Institute for Complex Systems Simulation Is this good? From: Warrington Cycle Campaign Cycle Facility of the Month (http://goo.gl/EiBnDv) Slide 3 Institute for Complex Systems Simulation Are these value for money? From: Warrington Cycle Campaign Cycle Facility of the Month (http://goo.gl/EiBnDv) Slide 4 Institute for Complex Systems Simulation How good is this? Slide 5 Institute for Complex Systems Simulation Capacity of Motor Infrastructure From: Transportation Research Board. (2010). Highway Capacity Manual. Slide 6 Institute for Complex Systems Simulation Capacity of Motor Infrastructure From: www.flownz.com Slide 7 Institute for Complex Systems Simulation Capacity of Pedestrian Infrastructure From: Halcrow Group Ltd. (2005) From: Colin Buchanan Ltd. (2010) From: Fruin, J. J. (1971). Pedestrian Planning and Design Slide 8 Institute for Complex Systems Simulation Capacity of Cycle Infrastructure From: Navin, F. P. D. (1994). Bicycle Traffic Flow Characteristics: Experimental Results and Comparisons. ITE Journal, (March), 3136. Slide 9 Institute for Complex Systems Simulation A Quote from Fruin [...] many authorities are using maximum capacity ratings for dimensioning pedestrian space. No evaluation or consideration of human convenience has been made in developing these design standards. The flow curves [... demonstrate] that the maximum capacity of a pedestrian traffic scheme is attained only when there is a dense crowding of pedestrians. From: Fruin, J. J. (1971). Pedestrian Planning and Design Slide 10 Institute for Complex Systems Simulation SourceUseType Capacity (bicycles per metre per hour) Design Std: UK ? CROW (2007) Design Std: Netherlands Empirical 75 - 187.5 (width dependent; NB. Comfort not absolute capacity) Botma (1995) Design Std: USA (HCM) Theoretical650 Vejdirektor atet (2012) Design Std: Denmark Theoretical Path up to 2.0m: 1000 Path over 2.0m: 1500 Navin (1994) None Empirical (with theoretical extrapolation) 4000 Capacity of Cycle Infrastructure Slide 11 Institute for Complex Systems Simulation What about Quality of Service? Botma (1995) assumed no impedance; i.e. fixed speed. Does this matter? Can we use simulation tools, take the best practice of the simulation of other modes and cross-apply it to find out? Slide 12 Institute for Complex Systems Simulation Use Pedestrian Modelling? Often continuous space (2D) models. Successful tools at variety of scales Pedroute Legion VisWalk From: Halcrow Group Ltd. (2005) From: Colin Buchanan Ltd. (2010) Slide 13 Institute for Complex Systems Simulation The Social Force Model Helbing, D., & Molnr, P. (1995). Social force model for pedestrian dynamics. Physical Review E, 51(5), 42824286. Motivation to act Slide 14 Institute for Complex Systems Simulation Our Model Purpose Do interactions matter? From: CXMagazine.com Slide 15 Institute for Complex Systems Simulation Our Model Implementation Agent Based Model 2 dimensional continuous space Unidirectional flow Fixed path width Parallel boundaries Slide 16 Institute for Complex Systems Simulation Our Model Force Generation Slide 17 Institute for Complex Systems Simulation SFM Directional Perception In Helbing and Molnr (2005): Slide 18 Institute for Complex Systems Simulation Our Model Directional Perception Slide 19 Institute for Complex Systems Simulation SFM vs Our Model Pedestrians (SFM)Cycles Future forces and squishiness Present forces and NOT squishy Limited directional perception More complex directional perception Continuous bounded speed Bounded speed with step minimum Unbounded accelerationBounded acceleration Slide 20 Institute for Complex Systems Simulation Our Model Parameters and Outputs Bicycle behavioural parameters: Generally from CROW (2007) Exploratory variables: Path Width and Bicycle Arrival Rate Output data: Average speed, average crashing proportion, average distance to the nearest bicycle, etc. Slide 21 Institute for Complex Systems Simulation Results Speed vs. Flow High Quality Variable Quality Poor Quality Slide 22 Institute for Complex Systems Simulation Results Crashes (No impedance) Slide 23 Institute for Complex Systems Simulation Results Crashes Flow breakdown with speed-selection occurs primarily as multi-bicycle collisions at the entry: Without speed-selection: Slide 24 Institute for Complex Systems Simulation SourceUseType Capacity (bicycles per metre per hour) CROW (2007) Design Std: Netherlands Empirical 75-187.5 (width dependent; NB. Comfort not absolute capacity) This ModelSimulationca. 500 Botma (1995) Design Std: USA (HCM) Theoretical650 Vejdirektor atet (2012) Design Std: Denmark Theoretical Path up to 2.0m: 1000 Path over 2.0m: 1500 Navin (1994) None Empirical (with theoretical extrapolation) 4000 Results Literature Comparison Slide 25 Institute for Complex Systems Simulation Conclusions Lack of robust quantitative measures for capacity or quality of service. Inherent assumption that service quality is satisfactory up to capacity bicycles do not interact in a meaningful way. Slide 26 Institute for Complex Systems Simulation Conclusions 2D microsimulation model using the SFM. Basic behavioural traits applied. Data show qualitatively different result... sudden collapse in quality of service. Modelling confirms intuition that we cant ignore service quality for non-trivial flow rates. Slide 27 Institute for Complex Systems Simulation Acknowledgements EPSRC Doctoral Training Centre grant: EP/G03690X/1 University of Southampton: Institute for Complex Systems Simulation www.icss.soton.ac.uk Transportation Research Group www.trg.soton.ac.uk IRIDIS High Performance Computing Facility (and support services) Slide 28 Institute for Complex Systems Simulation Questions? Paper at: https://db.tt/8APJ8Vrk Slide 29 Institute for Complex Systems Simulation Maths Slide 30 Institute for Complex Systems Simulation Our Model Algorithm Slide 31 Institute for Complex Systems Simulation Our Model Bicycle Operation Slide 32 Institute for Complex Systems Simulation Bicycle Arrival Rate Proximity Slide 33 Institute for Complex Systems Simulation Barriers to Cycling TfGM, 2011 Slide 34 Institute for Complex Systems Simulation Barriers to Cycling From: City of Copenhagen. (2011). Copenhagen: City of Cyclists - Bicycle Account 2010.