Map Simulator

Python script for generating odometry and measurement datasets to test SLAM Algorithms.

Usage

In a ROS system with roscore running:

python2.7 map_simulator.py [-p] [-s <search_paths>] [-h] -i <input_file> [-o <output_file>] [<param_name>:<param_value>]...

Command Arguments

Positional Arguments

• -i <input_file>, --input <input_file>: (String)
  Path to a JSON file containing the desired map, robot movement commands and parameters.

Optional Arguments

• -o <output_file>, --output <output_file>: (Optional, String)
  Path and filename where the output ROSBag file is to be saved. If none is provided, only the visualization will be run, without generating a ROSBag.
• -p, --preview: (Optional)
  Display a step-by-step imulation using MatPlotLib.
• -s <paths>, --search_paths <paths>: (Optional, String) [Default: “.:robots:maps”]
  Search paths for input and include files, separated by colons :.
• -h, --help: (Optional)
  Display usage help.

#### Parameter Override Any parameter defined in the following section can be defined from the command line as well, and not just from the json files. Parameters entered through the command line will override any values previously defined in the json files. To enter a parameter, its name and value must be entered separated by a colon-equal sign and using spaces between different parameters. E.g.:

python2.7 map_simulator.py ... meas_per_move:=1 odom_frame:=odom_combined ...

For more information on the possible parameters, please review the next section.

## Parameters The JSON input files can define the following parameters. If a given parameter is not defined in any of the files (main input file or included sub-files), then the default value will be used.

### Include

• include: (list of strings) [Default: None]
  Parameter files to be included during parsing for reusing parameters between experiments with a more convenient, reduced-typing, smarter approach.
  E.g.:
  

    "include": [
        "common.json",
        "map.json",
        "movements.json"
    ]
    

The include procedure is done in the following manner:

• recursively and in a depth-first order:
  If an included file contains include statement as well, the files listed are also included,
  E.g.: Input file contains:

     "include": [
         "a.json",
         "b.json",
         "c.json"
    ]
     

 and file `a.json` contains

     "include": [
         "d.json",
         "e.json"
    ]
     

 Then the include order will be: `a.json`, `d.json`, `e.json`, `b.json`, `c.json`.   * with ***duplicate detection***:<br/>   Parsed files are kept in a list and included only once, the first time (in depth-first order) it is included.   * ***last-in***:<br/>   The last definition of a parameter according to include order rules overrides any previous definitions.   ***Note:*** Included files are always parsed before any parameters configured locally in the file.

### TF #### TF Frames

• odom_frame: (String) [Default: “odom”]
  TF Frame for the odometry measurements.
• base_frame: (String) [Default: “base_link”]
  TF Frame for the robot’s base
• laser_frame: (String) [Default:”laser_link”]
  TF Frame for the Laser Sensor

TF Transforms

• base_to_laser_tf: (Array) [Default: [[0.05, 0.0], [0]] ]
  Transform between the base and laser frames in the format [[x, y], θ].

Map

• obstacles: (List of Objects) [Default: [] (Empty Map)]
  A world map is defined as a list of geometric obstacles.
  E.g.:

```json “obstacles”: [ {“type”: “polygon”, “vertices”: [[-0.1, 1.0], [10.1, 1.0], [10.1, 1.1], [-0.1, 1.1]]}, {“type”: “circle”, “center”: [4.0, 0.0], “radius”: 10},

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