VISSIM

VISSIM
Name	VISSIM
Developer	PTV Group
Released	0 1992
Latest release version	2024
Latest release date	March 2024
Operating system	Microsoft Windows
Genre	Traffic simulation, Transportation planning
License	Proprietary

VISSIM. VISSIM is a microscopic, behavior-based multi-modal traffic flow simulation software package developed by the PTV Group. It is a globally recognized standard tool used by transportation engineers, planners, and researchers to model and analyze complex traffic and transportation systems. The software simulates the movement of individual vehicles, cyclists, and pedestrians in realistic network environments to evaluate the performance of infrastructure under various conditions.

Overview

VISSIM operates as a discrete, stochastic, time-step-based microscopic simulation model, meaning it tracks the behavior of each road user individually over time. Its primary application is within the fields of transportation engineering, urban planning, and traffic management. The software is extensively utilized for analyzing intersections, evaluating adaptive traffic control systems like SCATS and SCOOT, and planning for major events or new developments such as airport terminals or shopping mall complexes. Its ability to model mixed traffic conditions, including public transport and freight transport, makes it applicable for projects worldwide, from assessing roundabout designs in Europe to managing expressway congestion in Asia.

Core Features and Functionality

The core of VISSIM's simulation is its psycho-physical car-following model, originally derived from the research of Rainer Wiedemann, and its rule-based lane-changing logic. These models replicate driver behaviors such as acceleration, deceleration, and gap acceptance under various roadway and traffic conditions. Key functionalities include detailed modeling of public transport operations, with explicit representation of bus stops, tram lines, and railway crossings. The software also features integrated emission and fuel consumption models based on the Handbook of Emission Factors for Road Transport (HBEFA), allowing for environmental impact studies. Furthermore, its COM interface enables advanced users to control simulations programmatically for complex, automated analysis scenarios.

Applications and Use Cases

VISSIM is applied to a vast array of transportation challenges. Common use cases include the operational analysis of signalized intersections, the design and validation of intelligent transportation systems (ITS), and the planning of dedicated bus lane networks. It is instrumental in evaluating the impacts of transportation demand management strategies, such as congestion pricing schemes similar to those in London or Singapore. Major infrastructure projects, like the expansion of the Gotthard Base Tunnel or the development surrounding Stadium Australia, often rely on VISSIM simulations for traffic forecasting and mitigation planning. The software is also used for safety assessments, simulating vehicle-vehicle conflicts and pedestrian interactions at complex interchanges.

Integration and Compatibility

VISSIM is designed to work within a broader ecosystem of transportation software. It integrates seamlessly with other PTV Group products, such as the macroscopic planning tool VISUM for dynamic traffic assignment. The software can import network data from Computer-aided design (CAD) files and Geographic information system (GIS) platforms like ArcGIS. For traffic signal optimization, it interfaces directly with external controllers via protocols like VAP and links to signal timing tools such as Synchro. This interoperability allows for a streamlined workflow from regional planning to detailed operational analysis, supporting projects funded by agencies like the Federal Highway Administration (FHWA) or the European Commission.

Technical Specifications and Modeling Approach

The simulation engine uses a fixed time step, typically one-tenth of a second, to update the position and state of every entity within the network. Vehicle movement is governed by the Wiedemann model, which differentiates between free-flow and car-following regimes based on perceived thresholds. The software employs a multi-resolution modeling approach, allowing certain network parts to be modeled in high detail while others are simplified. It supports the simulation of connected and autonomous vehicle technologies through custom driver model attributes. Visualization is provided through 2D and 3D graphical outputs, which can be used to create compelling presentations for stakeholders, including presentations to entities like the Transport for London authority.

Development and History

VISSIM was originally developed at the University of Karlsruhe (now the Karlsruhe Institute of Technology) in the early 1990s by a team including researchers like Rainer Wiedemann. The software's development was commercialized and has been continually advanced by the PTV Group, headquartered in Karlsruhe, Germany. Major milestones include the introduction of integrated pedestrian simulation, enhanced public transport modeling, and tools for analyzing electric vehicle charging infrastructure. Its ongoing development is heavily influenced by user feedback from a global community of practitioners and collaborations with research institutions such as the Technical University of Munich, ensuring it remains at the forefront of simulating emerging mobility trends.

Category:Traffic simulation Category:Transportation planning software Category:Proprietary software