SDFUtils 1.0.0

Gazebo SDF utils - write smaller and simpler xacro and get richer and complex SDF files

SDFUtils

Gazebo SDF utils. Write smaller and simpler xacro and get richer and complex SDF files.

basic usage:

python3 xacro2sdf.xacro2sdf input_xacro_file output_sdf_file

XACRO

• properties
• macro
• include
• pure python

properties

• declare variable to use by other sdf section

source sdf with xacro tags

<sdf xmlns:xacro="http://xacro">
    <xacro:property name="width" value=".2" />
    <xacro:property name="bodylen" value=".6" />
    <xacro:property name="x" value="1" />
    <xacro:property name="y" value="2" />
    <xacro:property name="z" value="3" />
    <link name="base_link">
        <pose>${x} ${y} ${z} 0 0 0</pose>
        <visual>
            <geometry>
                <cylinder radius="${2*width}" length="${bodylen}" />
            </geometry>
        </visual>
    </link>
</sdf>

output sdf

<sdf >
    <link name="base_link">
        <pose>1.0 2.0 3.0 0 0 0</pose>
        <visual>
            <geometry>
                <cylinder radius="0.4" length="0.6"/>
            </geometry>
        </visual>
    </link>
</sdf>

include

include other xacro files to use

• file:// : load files relative to sdf/xacro file
• package:// : load files from helper folder under script source folder

<xacro:include uri="file://data.xacro" />
<xacro:include uri="package://common.xacro" />
<xacro:include uri="package://color.xacro" />

• data.xacro: custom file hold data properties for example
• common.xacro: common macro's like inertia and basic geometry
• color.xacro: color and texture macro's

pure python

• use python inside your models, ident the same as in python (starting from column 0)!
• store your needed variables in "return_values" dictionary and use them later in the model by the given keys.

    <xacro:python>
    <![CDATA[
import numpy as np 
def foo(): 
    if 2 > 5: 
        return 5,4,3,2,1
    global np
    b = np.array([0,1])
    x = 3433
    y = 324
    z = 3
    m = 1
    return x,y,z,m,b
temp = foo()
return_values = {'x': temp[0], 'y': temp[1], 'z': temp[2], 'm': temp[3], 'b': temp[4]}
]]>
    </xacro:python> 

common

macros

• inertia_box
• inertia_sphere
• inertia_cylinder
• geometry_cylinder
• geometry_box
• geometry_sphere

color

macro

• color