FAQ

From sumo

Contents 1 General 1.1 What is SUMO? 1.2 What does "SUMO" mean? 1.3 What kind of a traffic simulation is SUMO? 2 Features 2.1 Does SUMO support traffic within the junctions? 2.2 Is it possible to connect SUMO to an external application (f.e. ns-2)? 2.3 Can SUMO simulate lefthand traffic? 2.4 Is it planned to simulate lefthand traffic one day? 2.5 Can SUMO generate movement traces? 3 Building / Installation 3.1 How do I access the Subversion repository? 3.2 Is there further documentation on Subversion? 3.3 How to check out revision 5499 (or any other outdated sumo)? 3.4 Which platforms are supported? 3.5 Troubleshooting 4 Basic Usage 4.1 What measures are used/represented? 4.2 What does the following error mean? 5 NETCONVERT 5.1 Segmentation Fault while building a Road Network 5.2 Can I import the free network of Osnabrück "Frida"? 5.3 Are there any other free networks available I can use? 5.4 The application hangs after a while (few memory consumption, most of the system time) (Windows) 5.5 NETCONVERT aborts at step 12 (Computing node shapes) 6 Router 6.1 No random routes are generated though using the -R option 6.2 Less random routes than defined using -R 7 Simulation 7.1 How to simulate an accident 7.2 I have changed my network and now SUMO does not load it. 7.3 No vehicle appears 7.4 Vehicle jumps backward 7.5 How do I change the duration of cycles and phases? 7.6 I can not see a vehicle moving in my simulation 8 Visualisation 8.1 GUISIM breaks 8.2 Display flickers in the area of the mouse pointer (Windows) 8.3 Loading of a jpeg/png fails 8.4 GUISIM finishs with: FATAL: exception not rethrown (Linux) 8.5 GUISIM windows and buttons appear but no net/cars are visible

General

What is SUMO?

SUMO is a traffic simulation package. It is meant to be used to simulate networks of a city's size, but you can of course use it for smaller networks and larger, too, if your computer power is large enough.

What does "SUMO" mean?

"SUMO" is an acronym for "Simulation of Urban MObility".

What kind of a traffic simulation is SUMO?

SUMO is a microscopic, space-continuous road traffic simulation. In the next time it will be extended to be multi-modal.

Features

Does SUMO support traffic within the junctions?

Yes, SUMO supports inner-junction traffic since version 0.9.5.

Is it possible to connect SUMO to an external application (f.e. ns-2)?

There are several approaches to do this, see (http://sumo.sourceforge.net/wiki/index.php/Main_Page#Related_to_C2C)

Can SUMO simulate lefthand traffic?

No.

Is it planned to simulate lefthand traffic one day?

Would be definitely a nice feature and we would support anyone who wants to implement it. As we are not involved in projects were lefthand traffic is wished, we are not capable to do this work by ourselves.

Can SUMO generate movement traces?

Most of the C2C-extensions do this, see (http://sumo.sourceforge.net/wiki/index.php/Main_Page#Related_to_C2C)

Building / Installation

How do I access the Subversion repository?

There are plenty of subversion clients for all platforms. If you use the command line client, you can checkout sumo using the following command:

 svn co https://sumo.svn.sourceforge.net/svnroot/sumo/trunk/sumo

For later updates go inside the sumo directory, which has been created, and simply type svn up.

Is there further documentation on Subversion?

There are the Sourceforge documentation and the Subversion book.

How to check out revision 5499 (or any other outdated sumo)?

You can use the SVN option "-r <REVISION_NUMBER>" together with the checkout on the command line. You have to consult your client's documentation if you use a graphical interface. Please be aware of the fact that we can only give very limited support for older versions.

Which platforms are supported?

We compile regularly under Windows XP using Visual Studio 2005 (aka MSVC 8) and have daily builds on Linux (openSUSE 10.3 and 11.1 with gcc4). We would be happy to hear about successful builds on other platforms. We already heard about successful builds (without GUI) on MacOS X, Solaris and Cygwin.

Troubleshooting

See LinuxBuild or WindowsBuild.

Basic Usage

What measures are used/represented?

All time values are given in seconds. All length values are given in meters. This means that speed should be given in m/s, etc.

Currently, each simulation time step is one second long (to be exact: in each simulation step one second real time is simulated).

What does the following error mean?

Warning: No types defined, using defaults... Error: An exception occurred! Type:RuntimeException, Message:The primary document entity could not be opened. Id=<PATH> Error: (At line/column 1/0). Error: Quitting (conversion failed).

Answer: Simply that the file you try to use (<PATH>) does not exist. This is xerces' way to say "file not found".

NETCONVERT

Segmentation Fault while building a Road Network

It was reported that NETCONVERT breaks with a segmentation fault under Ubuntu Linux in step 12 "Computing node shapes". It seems that the reason is due to a broken (?) version of the GDAL library. You probably have to install your own one or try to build NETCONVERT with no GDAL support.

Can I import the free network of Osnabrück "Frida"?

Yes and no. You import it using NETCONVERT, a description is available at http://sumo.sourceforge.net/docs/gen/sumo_moreon_arcview.shtml#more_arcview-frida. Still, this may be a good gis-network but lacks some needed information in order to be usable for simulations (see discussion at the link above).

Are there any other free networks available I can use?

Actually, we have not yet spent so much time for finding open source networks. Take a look at http://sumo.sourceforge.net/docs/gen/sumo_moreon_arcview.shtml in order to find some further information. That's all we know by now.

The application hangs after a while (few memory consumption, most of the system time) (Windows)

You are propably running a program compiled in the debug-mode. This yields in at least the triple of normal memory usage and your system may not be able to solve. Try to use the normal version, build in Release-mode (or buy more RAM :-) ).

NETCONVERT aborts at step 12 (Computing node shapes)

Please check whether the network you try to import is encoded in geocoordinates. If so, try to convert it with the option --use-projection with a properly defined projection using --proj <PROJ_DEF>.

Router

No random routes are generated though using the -R option

On the one hand, SUMO-routers quit processing if a route could not be build. On the other hand, the generation of a random route may fail quite easily, simply because it's too short or no connection could have been found. If you have made everything right, but your route file is empty, try to use the --continue-on-unbuild switch on your command line / within your configuration file.

Less random routes than defined using -R

The number of generated vehicles which start per second may be lower than the value specified using -R if no route could be found between two randomly chosen edges.

Simulation

How to simulate an accident

Currently, there are two possibilities to simulating something like an 'accident':

1. Let a vehicle halt on the lane for some time (see http://sumo.sourceforge.net/docs/gen/user_chp06.shtml#user_chp06-management-public). This works quite nice for simulating accidents.

2. Put a variable speed sign of the lane where the accident is meant to be and let it reduce the speed (see http://sumo.sourceforge.net/docs/gen/user_chp06.shtml#user_chp06-management-vss). This method will reduce the throughput on the lane, but further dynamics will rather not fit to what one would expect from an accident situation.

1+2. You may of course combine both approaches. Within TrafficOnline, we simulated traffic incidents by letting vehicles stop on one lane and reducing the speed on the other lanes.

I have changed my network and now SUMO does not load it.

Actually, SUMO-networks are not meant to be edited by hand. You have to describe everything within the your input properly and let NETVCONVERT build your network. Editing networks by hand is very complicated and error-proned.

No vehicle appears

We encountered this problem under the following circumstances: As we imported a network where the maximum speed allowed on was given in km/h instead of the supposed m/s, no vehicle could be emitted due to a too large space needed for oncoming traffic. Check whether your network description also defines speed in km/h. If so, use the SUMO-NETCONVERT - switch "speed-in-kmh" to recompute the speed limits. If this does not help, contact us.

Vehicle jumps backward

When I try to evaluate my vehicle dump, sometimes vehicle seem to jump backward (their position is smaller than in the previous step)

To avoid jams due to an inappropriate lane changing behaviour, vehicles may swap their lanes. In this case each vehicle obtains the position and speed of the other vehicle. As the position of the vehicles may differ a bit, one of the vehicles may seem to jump backwards.

This should not happen from Version0.8 on.

How do I change the duration of cycles and phases?

If you have a network that contains traffic lights, you can open it with a text editor. Then search for "tl-logic". You will find the definition(s) of your traffic light(s). Now, you can see a set of "phase"-definitions within each of the traffic lights definitions. You can change the time for each phase directly in here.

See also the documentation on traffic light (Traffic Lights) and (SUMO - More on... Traffic Lights).

I can not see a vehicle moving in my simulation

There may be two reasons why you do not see the cars.

1. If your simulation area is too big, cars will not be displayed unless you zoom into the net. The reason is that cars are displayed if their visible size is larger than 1 pixel in order to improve the visualization speed by avoiding drawing all the streets and cars even if the cars would not be visible. You may also change the settings by clicking to the color wheel in guisim, selecting the "vehicles" panel and changing the value of "minimum size to show" to zero.

2. The simulation is too fast so that all vehicles disappear before being seen. To avoid this, you may increase the "Delay"-value what makes the simulation wait between simulation steps.

Visualisation

GUISIM breaks

Sometimes guisim terminates with no reason. In most cases, an update of the opengl-driver solves this problem.

Display flickers in the area of the mouse pointer (Windows)

Newer Windows-Versions seem to cache the area under the mouse to apply the mouse shadow afterwards. To avoid this, go to your Systemmenu, then Mouse->Pointers and disable the mouse shadows. That's the only solution so far. (Origin: Till Oliver Knoll, via QT Interest List)

Loading of a jpeg/png fails

Currently (version 0.9.7), GUISIM is not capable to load jpegs and pngs. We will try to add a spuurt for these formats in the next time.

GUISIM finishs with: FATAL: exception not rethrown (Linux)

This is a known bug in the pthreads library. The last link also shows how to patch fox in order to avoid this.

GUISIM windows and buttons appear but no net/cars are visible

You have most definitely an opengl problem. Even recent (as of 01/2009) software implementations (for instance mesa together with the radeon driver on X) are buggy. Some workarounds are mentioned at the end of this thread.