Vehicles and Traffic

A complete virtual world generation process needs realistic, attractive, polygon-efficient, dynamic models of every sort of contemporary vehicle that may travel on, above or around a virtual terrain.  Desirable: several levels of details, working indicator lights, and at least external moving parts should move.  Rather disorganized notes follow...

Raw Models

• as far as i can tell, there are no sources of fully-implemented vehicles, commercial or otherwise, so we must start with a simple mesh, or adapt models which are already designed for some specific simulation environment
• Commercial and "free" models are easily available from site like Turbo Squid or CGTrader
  • However, even the so-called "free" models cannot generally not be redistributed, greatly limiting their usefulness.  Each model has its own copyright and license.  A handful of models have Creative Commons or similarly flexible licenses.
• The SketchUp 3D Warehouse also has many vehicle models.
  • However, permission to use the models there are quite confusing.  From the Terms of Service:
  • "By submitting [..] Content through the 3D Warehouse, you grant end users a worldwide, royalty-free, non-exclusive, perpetual license to: 1. to reproduce the Content; 2. to create and reproduce derivative works of the Content; 3. to display publicly and distribute copies of the Content; 4. to display publicly and distribute copies of derivative works of the content."
  • That sounds good.  However, "end users may not [..] use or distribute Content obtained from the 3D Warehouse in a mapping or geographic application or service without Google’s prior authorization."

• To make models uniform for the VTP software, it is highly useful to define some Vehicle Modeling Conventions

Vehicles - Ground

• Road-Vehicle Physics (Dynamics and Simulation)
  • need simple road dynamics - e.g.. velocity-based movement, terrain following and collision detection
  • Open Dynamics Engine (ODE)
    • free, industrial quality library for simulating articulated rigid body dynamics - for example ground vehicles
    • a simple open-source example: Carworld Car Simulation using ODE
  • OpenDS
    • A free, EU-funded, open-source driving simulator for R&D in the automotive industry as well as scientific studies.
    • Main contributor is the Automotive Group at the German Research Center for Artificial Intelligence (DFKI).
  • some existing commercial software:
    • Havok (merged with Ipion)
      • "Enjoy driving full physically modeled cars!"
      • executable vehicle demos available; no price/licensing costs on their website
    • FastCar™
      • simulates vehicles, with strong claims of "speed, physical accuracy and ease of use"
      • intended to be licensed by game developers for $5-20k
    • Carsim/Trucksim from Mechanical Simulation Corporation
      • "Vehicle dynamics simulation has never been easier, faster, or more configurable."
      • an integrated set of tools for simulating and analyzing dynamic acceleration, braking and handling of cars and light trucks under a variety of simulated test conditions
      • it's not clear whether it could work for realtime use
      • physics core is Mathworks MATLAB/Simulink
  • The  Newton Game Dynamics engine is closed-source but is portable and has a flexible license.  There are examples available of using it for vehicle simulation.
• Network Behavior - Traffic
  • also need simple traffic-following behavior - e.g.. cars that know to slow down for curves, stop at red lights, and don't drive into each other
  • SUMO - Simulation of Urban MObility
    • An open-source (GPL), cross-platform, microscopic, multi-modal and continuous road traffic simulation software being developed by two big German research organizations, the DLR and the ZAIK.
    • Built on GDAL, Xerces and Fox Toolkit for a GUI.
    • User documentation for the applications is online.
  • Hank Driving Simulation at the University of Iowa
  • Smartest: Analysis of Micro-Simulation Tools is a huge list of traffic simulators, both free and commercial, as of 1998.  Many are now defunct, others much improved.
  • MITSIM (from MIT) is one of the better live academic ones
  • Paramics (UK-based) and VISSIM (Germany) are two common commercial versions
    
  • TSS AIMSUM (Barcelona) had a quite sophisticated 3D option (AIMSUM 3D) even back in the 1990s; as of 2008 the 3D is integrated into the main application
    
  • Trafficware Synchro Studio has become popular as of 2006.
    •  It has a 3D Viewer (additional $1000), listed under Commercial Terrain Tools
  • TSIS CORSIM was apparently the most widely-used back in 2000, since eclipsed by newer, slicker software
  • TransModeler Traffic Simulation Software ($10,000) from Caliper (Massachusetts)
    • added 3D viz with their 2.0 version
    • "incorporates all the benefits of a GIS, a traffic simulator and a 3D visualization tool"
    • 
  • Physics of Transport and Traffic [http://www.traffic.uni-duisburg.de/]
    • The Nagel-Schreckenberg-Model Traffic Simulator (Java applet)
  • Washington Post: Lab Studying Science Behind Traffic Patterns
    • "Barrett's team is creating a vast, mirror world in cyberspace of every motorist and transit rider"
  • Scientific American article, Unjamming Traffic with Computers (now seems to be offline, cached here)
  • are there any standards for data format, for representing traffic flow in road networks?  it appears the answer is no.  Paramics does have a fairly straightforward text format.

Vehicles - Air

• see Airports and Airplanes: Leveraging the Flight Simulation Field
• Airplanes
  • Raw models.  There are e.g. 747 and DC10 models which are free, but often lack important parts like landing gear.  This info has to be dug up with web research, e.g. a 747 has "16 49-inch main landing gear tires and two nose landing gear tires."
  • Simulation
    • LaRCsim is a set of ANSI C routines that implement a full set of equations of motion for a rigid-body aircraft, from "NASA LaRC"
  • Aircraft types and airline markings
    • United Seat Maps has pictures of every type of aircraft and exact seating
• CIGI (Common Image Generator Interface) project
  • CIGI's Multi-Purpose Viewer (MPV) has a Content archive which includes a number of military-oriented vehicle models collected from various free sources, which are redistributable to varying degrees.  As of March 2006, this includes:
  • from 3dkingdom.org: F4E-Phantom, F15, SU-34, SU-47-Slika
  • from CSP: F22
  • from Delta3D's asset library (from CSC and MOVES): F18c_hornet, helix, mi24_hind, MV-22, UH-1N
  • from Digitalanimators.com: Cessna140, Hind-24H
  • from Exchange3d.com: SU-37
  • from Turbosquid: A-6, Apache, F-22, U2, A-10, C-47

Vehicles - Water

• Some boat applications include Sail Simulator (€25), Virtual Sailor ($30), and Ship Simulator (€17).
• Those apps contains lots of great boat models - "from massive cargo ships and ferries, to speedboats, yachts, water taxis and even the mighty Titanic."
• However, they are closed-source commercial apps, no model sharing.