image2gazebo

Generates SDF model for Gazebo Simulator using a simple PNG file.

0. Parameters

# USAGE:
$ ./create_world.sh RESOLUTION HEIGHT MODEL_NAME INPUT_PNG_FILE

• RESOLUTION: Size of each pixel in the PNG file in meters. If given 0.05 each pixel will shown in Gazebo as 5cm in X and Y axes.
• HEIGHT: Height of the model in Gazebo in meters.
• MODEL_NAME: Your model name without fancy characters and whitespaces. Use underscore instead of whitespace.
• PNG_FILE: Image file made by you.

1. Drawing the Image File

I personally prefer using Pinta but you can draw your bitmap with any drawing program.

• Firstly, you must decide on the size of the map in meters. I will go with 10 meter * 30 meter.
• Secondly, you must decide on the resolution of the model. Since it is like a maze I will go for 10 cm (= 0.1 meter).
• Open your preferred drawing program and set the image size as x_size/resolution and y_size/resolution. In our example these values are 10.0/0.1 = 100 and 30.0/0.1 = 300. So I prepared my image with the size of 100 x 300.
• Now you can draw. But remember, according to our example every pixel will be 0.1 meter x 0.1 meter.
• Lastly, you must decide on the height of the map. Since I will use a robot like P3AT, I will set this value as 1.0 meter.

1. Generating the Model

• Generate the example model:

$ ./create_world.sh 0.1 1.0 my_png_model map.png

• This command will create a folder like below. This is your model:

2. Installing the Model

There are two different ways:

2.1. Installing to Local Gazebo's Models Folder

• Copy the generated folder into ~/.gazebo/models/
• Now you can insert the model in Gazebo Simulator.

2.2. Installing to a ROS Package's Models Folder

• Create a models folder in your ROS package and copy your model into it.
• When running your simulator with a launch file add this line: (Don't forget to change YOUR_PACKAGE_NAME)

<env name="GAZEBO_MODEL_PATH" value="$(find YOUR_PACKAGE_NAME)/models" />

• Now the Gazebo should be able to find your model. You can modify your world file accordingly.