Add motor xacro macro; add base_footprint macro; fix base collision; fix wheel inertia;

config/diffbot/base.yaml

@@ -1,6 +1,7 @@
 base:
-  mass: 2.5               # Base mass in Kg
+  mass: 0.8               # Base mass in Kg
   x_size: 0.195           # Dimension in x axis
-  y_size: 0.198           # Dimension in y axis
-  z_size: 0.182           # Dimension in z axis
+  y_size: 0.08            # Dimension in y axis
+  z_size: 0.005           # Dimension in z axis
   mesh: 'chassis.stl'  # Name of the mesh files. Leave it empty ('') to have a white base.
+  #mesh: ''

config/diffbot/front_wheel.yaml

@@ -1,8 +1,9 @@
 wheel:
   mass: 0.01        # Wheel mass in Kg
-  radius: 0.011     # Wheel radius in m
-  length: 0.006     # Wheel length in m, considering is as a cylinder
+  radius: 0.0331    # Wheel radius in m
+  length: 0.025     # Wheel length in m, considering is as a cylinder
   mesh: 'wheel.stl'          # Name of the mesh files. Leave it empty ('') to have a red wheel
-  x_offset: 0.035
-  y_offset: -0.056
-  z_offset: 0.008
+  #mesh: ''
+  x_offset: 0.079
+  y_offset: 0.015
+  z_offset: -0.017

config/diffbot/motor.yaml

@@ -0,0 +1,9 @@
+mass: 0.1          # Motor mass in Kg
+x_size: 0.07       # Motor dimension in x axis
+y_size: 0.0225     # Motor dimension in y axis
+z_size: 0.0188     # Motor dimension in z axis
+mesh: 'motor.stl'  # Name of the mesh files. Leave it empty ('') to have a red wheel
+#mesh: ''
+x_offset: 0.096
+y_offset: -0.0135
+z_offset: -0.017

urdf/diffbot.gazebo.xacro

@@ -0,0 +1,35 @@
+<?xml version="1.0"?>
+<robot xmlns:xacro="http://ros.org/wiki/xacro">
+
+  <!-- ros_control plugin -->
+  <gazebo>
+    <plugin name="gazebo_ros_control" filename="libgazebo_ros_control.so">
+      <robotNamespace>/diffbot</robotNamespace>
+      <!--robotParam>/robot_description</robotParam-->
+      <robotSimType>gazebo_ros_control/DefaultRobotHWSim</robotSimType>
+    </plugin>
+  </gazebo>
+
+  <!-- xacro to set the friction for the wheel. This patch was taken from the MIR
+  repository. 
+    https://github.com/dfki-ric/mir_robot/tree/noetic.
+    https://github.com/dfki-ric/mir_robot/blob/a216d7374c21e360c94034d360b07fd7a4d42842/mir_description/urdf/include/mir_100.gazebo.xacro#L29
+   -->
+  <xacro:macro name="set_wheel_friction" params="link friction">
+    <gazebo reference="${link}">
+      <mu1 value="${friction}"/>
+      <mu2 value="${friction}"/>
+      <kp value="10000000.0"/>
+      <kd value="1.0"/>
+      <minDepth>0.01</minDepth>
+    </gazebo>
+  </xacro:macro>
+
+  <xacro:macro name="set_all_wheel_frictions" >
+    <xacro:set_wheel_friction link="back_left_wheel" friction="200"/>
+    <xacro:set_wheel_friction link="front_left_wheel" friction="200"/>
+    <xacro:set_wheel_friction link="back_right_wheel" friction="200"/>
+    <xacro:set_wheel_friction link="front_right_wheel" friction="200"/>
+  </xacro:macro>
+
+</robot>

urdf/diffbot.urdf.xacro

@@ -1,30 +1,36 @@
 <?xml version="1.0"?>
-<robot xmlns:xacro="http://www.ros.org/wiki/xacro" name="mobile_robot">
+<robot xmlns:xacro="http://www.ros.org/wiki/xacro" name="diffbot">
 
-  <xacro:property name="package_name" value="mobile_robot_description"/>
+  <xacro:property name="package_name" value="diffbot_description"/>
   <xacro:property name="robot_name" value="diffbot"/>
 
   <xacro:include filename="$(find ${package_name})/urdf/include/common_macros.urdf.xacro" />
-
-  <!-- <xacro:set_package_name /> -->
+  <xacro:include filename="$(find ${package_name})/urdf/include/common_sensors.xacro" />
+  <xacro:include filename="$(find ${package_name})/urdf/diffbot.gazebo.xacro" />
 
   <xacro:property name="caster_wheel_yaml" value="$(find ${package_name})/config/${robot_name}/caster_wheel.yaml" />
   <xacro:property name="caster_wheel_props" value="${load_yaml(caster_wheel_yaml)}"/>
 
   <xacro:property name="front_wheel_yaml" value="$(find ${package_name})/config/${robot_name}/front_wheel.yaml" />
   <xacro:property name="front_wheel_props" value="${load_yaml(front_wheel_yaml)}"/>
 
+  <xacro:property name="motor_yaml" value="$(find ${package_name})/config/${robot_name}/motor.yaml" />
+  <xacro:property name="motor_props" value="${load_yaml(motor_yaml)}"/>
+
   <xacro:property name="base_yaml" value="$(find ${package_name})/config/${robot_name}/base.yaml" />
   <xacro:property name="base_props" value="${load_yaml(base_yaml)}"/>
 
 
+  <!-- Footprint link -->
+  <xacro:footprint wheel_props="${front_wheel_props}" />
+
   <!-- Base link -->
   <xacro:base base_prop="${base_props}" mesh="${base_props['base']['mesh']}" >
     <origin xyz="0 0 0" rpy="0 0 0" />
   </xacro:base>
 
   <!-- Back Caster Wheel -->
-  <xacro:caster_wheel prefix="caster_wheel" reflect="-1"
+  <xacro:caster_wheel prefix="rear" reflect="-1"
                       wheel_props="${caster_wheel_props}">
   </xacro:caster_wheel>
 
@@ -40,8 +46,23 @@
                       base_props="${base_props}"
                       mesh="${front_wheel_props['wheel']['mesh']}"> 
   </xacro:wheel>
+
+
+  <!-- Motors -->
+  <xacro:motor prefix="right" reflect="-1" 
+                      motor_props="${motor_props}"
+                      base_props="${base_props}"
+                      mesh="${motor_props['mesh']}"> 
+  </xacro:motor>
+
+  <xacro:motor prefix="left" reflect="1" 
+                      motor_props="${motor_props}"
+                      base_props="${base_props}"
+                      mesh="${motor_props['mesh']}"> 
+  </xacro:motor>
 
 
-  <!-- <xacro:include filename="$(find mobile_description)/urdf/mobile_robot_gazebo_plugins.xacro"/>  -->
+  <!-- Sensors -->
+
 
 </robot>