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微观交通仿真及其应用 初连禹 lchu@berkeley.edu 加州创新交通研究中心 加州交通管理实验室. 长春, 2006 年 8 月 26 日. Introduction. Microscopic simulation a software tool to model traffic system, including roads, drivers, and vehicles, in fine details. models: AIMSUN, CORSIM, MITSIM, PARAMICS, VISSIM… Why simulation?
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微观交通仿真及其应用初连禹lchu@berkeley.edu加州创新交通研究中心加州交通管理实验室微观交通仿真及其应用初连禹lchu@berkeley.edu加州创新交通研究中心加州交通管理实验室 长春,2006年8月26日
Introduction • Microscopic simulation • a software tool to model traffic system, including roads, drivers, and vehicles, in fine details. • models: AIMSUN, CORSIM, MITSIM, PARAMICS, VISSIM… • Why simulation? • Can capture detailed traffic flow dynamics • Can be calibrated to reproduce real world scenarios • Can provide a visualization tool to evaluate traffic management and operational strategies • answer “what if” questions
Applications • Online/off-line applications • Evaluate traffic management and operational improvements • Model and Evaluate ITS • Calibrate / optimize operational parameters of ITS strategies • Develop / test new models, algorithms, control strategies
Paramics model • PARAMICS: PARAllel MICroscopic Simulation • a suite of software tools for micro traffic simulation, including: • Modeller, Analyzer, Processor, Estimator, Programmer • developer: Quadstone, Scotland • Features • large network simulation capability • modeling the emerging ITS infrastructures • OD estimation tool • Application Programming Interfaces (API) • access core models of the micro-simulator • customize and extend many features of Paramics • model complex ITS strategies • complement missing functionalities of the current model
User Input Interface Professional Community Oversight Output Interface GUI Tools Developer How to model ITS:Application Programming Interfaces Core Model API
PARAMICS API Main simulation loop API Plugins function calls: vehicle related.. link related.. and others user-defined programs functions data Other applications /APIs
PARAMICS Plug-in Development Adaptive Signal Control Advanced Algorithms Adaptive Ramp Metering Dynamic Network Loading Signal Provided API Library Ramp ATMIS Modules Routing Demand Developed API Library CORBA Data Handling Databases XML
Vissim vs Paramics • Paramics is better in following aspects: • Large-scale network modeling • Faster simulation speed • API • OD estimation tool • Conversion tool • Vissim excels in • Car-following model • Easy learning • Vissum, as planning model
Data needs • Coverage • Accuracy • Data processing
Model Calibration • Model needs to be calibrated before applications • Capacity calibration • OD Estimation • Route choice calibration • Bottleneck calibration
Proposed calibration targets • Flow • Within 25%-75% percentile • Due to traffic congestion, variation • Speed contours • Three levels of targets • Visual assessment • Match Bottleneck Area • Detailed Bottleneck Calibration
Signal control • Signal • Hardware-in-loop, testing 170 controller • Adaptive signal control based on real-time delay estimation
Evaluation of Adaptive Ramp Metering Algorithms • Algorithms • ALINEA, BOTTLENECK, ZONE • Morning peak hour (6:30-10:00) • High Demand • Low Demand • Scenarios • Recurrent congestion • Non-recurrent congestion • Incidents: block the rightmost lane for 10 minute • at the beginning of congestion • at the end of congestion
Optimization of parameters of ALINEA • ALINEA, • A local feedback ramp-metering strategy • Optimization method: • Hybrid method: simulation + GA
Ramp Metering Evaluation Platform • What is it? • A simple platform to guide Caltrans personnel on how to successfully manipulate the various aspects of the ramp-metering systems, including initializing parameters, fine tuning of parameters, performance analyses, and hypothetical "what if" simulated testing. • What does it consist of? • A library of metering algorithms either currently or potentially applied in California is included in this platform. The platform has intuitive graphical interfaces in order to facilitate Caltrans practitioners. • How has it been used? • Not yet deployed. • How can it be used? • provides a quick and cost-effective way to conduct ramp-metering studies.
Evaluation of Traffic Delay Reduction from AWIS • Work zone • Noticeable source of accidents and congestion • AWIS: • Automated Workzone Information Systems • Components: • Sensors • Portable CMS • Central controller • Benefits: • Provide traffic information • Potentially • Improve safety • Enhance traffic system efficiency
Corridor management Plan Demo • Goal: • to incorporate detailed multi-modal performance measurement and operational analysis into the traditional corridor planning efforts. • Major Tool: • Microscopic Traffic Simulation (Paramics) • Outcome: • A template for Caltrans to use in corridor planning efforts that will integrate both planning and operations • To help to address the problem of lost system productivity during congestion, thereby improving mobility in the most cost effective manner.
I-880 improvement projects • Interchange improvement • SR-92 • Davis • Marina • Mission Blvd • Freeway mainline improvement • Extend HOV lanes • Add one more lane to both NB and SB SR-238 • Construct auxiliary lanes • Add an aux lane along SB 880 from SR-238 to A St. • Add an aux lane along NB 880 from Tennyson to SR-92 • Arterial improvement • Widen Stevenson from 4 to 8 lanes • …
I-880 improvement projects I-880 SR92 Current I-880/SR92 Interchange
Proposed Improvements A & B A: Add 3- lane facility on SR92 EB which continues until I-880 interchange B: Remove a diagonal ramp to Hesperian NB and add two left turn lanes on loop ramp to Hesperian SB B A
Proposed Improvements C, D, E, & F C: Remove SR92 to 880NB loop and add 3 lane flyover ramp(1 lane for HOV only). D: Improve the curvature of 880SB to SR92 WB E: Improve the curvature of 880NB to SR92 EB F: Remove SR92 to 880SB loop and add 1 lane flyover ramp F E D C
Proposed Improvements G & H G: Add 1 aux lane on 880SB until Tennyson Rd H: Add 1 aux lane on 880 NB from Tennyson Rd H G
Proposed Improvements I & J I I: Add 1 aux lane on 880 NB until Winton Ave J: Add 1 aux lane on 880 SB from Winton Ave J
Benefit Analysis of Selected Proposed Orange County Freeway Improvement Projects • Project 1: Re-stripe left shoulder of I-5 between SR-55 interchange and SR-22/SR-57 interchange to add second HOV (High Occupancy Vehicle) lane. • Project 2: Re-stripe left shoulder on I-5 between Tustin Ranch Road and SR-133 interchange to add continuous auxiliary lane. • Project 3: Extend existing HOV lane on SR-55 from the I-405 to Victoria in both directions. • Project 4-1: Add one general purpose lane on I-5 between the Orange/San Diego County line and Camino Capistrano. • Project 4-2: Extend HOV lane on I-5 between the Orange/San Diego County line and Camino Capistrano.
Re-stripe left shoulder of I-5 between SR-55 interchange and SR-22/SR-57 interchange to add second HOV (High Occupancy Vehicle) lane
Re-stripe left shoulder on I-5 between Tustin Ranch Road and SR-133 interchange to add continuous auxiliary lane
Extend existing HOV lane on SR-55 from the I-405 to Victoria in both directions
Add one general purpose lane on I-5 between the Orange/San Diego County line and Camino Capistrano
Extend HOV lane on I-5 between the Orange/San Diego County line and Camino Capistrano
ATMS Training and Development System • What is it? • A high-end simulator for use in Caltrans operator training efforts as well as a true testing facility for ATMS upgrades and enhancements within an environment with the full functionality of a Caltrans TMC. • What does it consist of? • An ITS Test Center and TMC Simulator that provides connectivity to the Testbed’s real-time data streams (field and simulated). Provides both “live”and “virtual” connections to Caltrans field traffic control systems. An adjoining “classroom” has capacity for fifteen Caltrans trainees. • How has it been used? • Provides Caltrans TMC operator training. • How can it be used? • Test and evaluate upgrades/enhancements to TMC operations in a secure environment that exactly duplicates actual TMC software systems and data feeds.
ATMS Training and Development System loop data incident ramp metering, CMS messages
Effects by Allowing Single Occupant Hybrid Vehicles on HOV Lanes • Objective: Evaluate the impacts of allowing use of High Occupancy Vehicle (HOV) lanes by single-occupant gasoline-electric hybrid vehicles • Three major components: • microscopic simulation modeling, • emission modeling for HOV/hybrid system, • demand modeling for future hybrid vehicles. • Scenarios considered
Effects by Allowing Single Occupant Hybrid Vehicles on HOV Lanes (cont.)
Extension of Hybrid HOV Lane Micro-simulation Model • Evaluation of the impacts of: • allowing single-occupant vehicles to pay a toll to use the HOV lanes (so-called HOT lanes) • the use of Caltrans District 12 HOV lanes as a part time system with no buffer separating the lanes (similar to the HOV system that exists in Caltrans District 4) • Investigate the impacts of: • Priority-based HOV operation
Distributed Paramics Modeling • Global Network Database • Global Network Monitoring • Global Path Calculation • Path Tree Storage Global Path Controller CORBA middle ware Network Monitoring API Network Monitoring API Network Monitoring API Network Monitoring API Vehicle Routing API Vehicle Routing API Vehicle Routing API Vehicle Routing API Subnet Simulator 4 Subnet Simulator 2 Subnet Simulator 3 Subnet Simulator 1 Other Supporting APIs Other Supporting APIs Other Supporting APIs Other Supporting APIs Other Supporting APIs Other Supporting APIs Other Supporting APIs Other Supporting APIs Other Supporting APIs Other Supporting APIs Other Supporting APIs Other Supporting APIs Computer 3 Computer 2 Computer 4 Computer 1 Sub-network Simulation Components