Desk model: ground added

urdf/drawer_desk/desk.urdf

@@ -19,7 +19,30 @@
   <material name="light_purple">
     <color rgba="0.3 0.3 0.6 1"/>
   </material>
+  <material name="black">
+    <color rgba="0.05 0.05 0.05 1"/>
+  </material>
   <link name="world"/>
+  <link name="ground">
+    <visual>
+      <geometry>
+        <box size="5 5 0.1"/>
+      </geometry>
+      <origin rpy="0 0 0" xyz="0 0 0"/>
+      <material name="black"/>
+    </visual>
+    <collision>
+      <geometry>
+        <box size="5 5 0.1"/>
+      </geometry>
+      <origin rpy="0 0 0" xyz="0 0 0"/>
+    </collision>
+  </link>
+  <joint name="world_ground_joint" type="fixed">
+    <parent link="world"/>
+    <child link="ground"/>
+    <origin rpy="0 0 0" xyz="0 0 -0.05"/>
+  </joint>
   <link name="board">
     <visual>
       <geometry>

urdf/drawer_desk/desk.urdf.xacro

@@ -6,8 +6,36 @@
 	<xacro:include filename="case.urdf.xacro"/>
 	<xacro:include filename="drawer.urdf.xacro"/>
 
+	<xacro:property name="ground_thickness" value="0.1"/>
+
+	<material name="black">
+		<color rgba="0.05 0.05 0.05 1"/>
+	</material>
+
 	<link name="world"/>
 
+	<link name="ground">
+		<visual>
+			<geometry>
+				<box size="5 5 ${ground_thickness}"/>
+			</geometry>
+			<origin xyz="0 0 0" rpy="0 0 0"/>
+			<material name="black"/>
+		</visual>
+		<collision>
+			<geometry>
+				<box size="5 5 ${ground_thickness}"/>
+			</geometry>
+			<origin xyz="0 0 0" rpy="0 0 0"/>
+		</collision>
+	</link>
+
+	<joint name="world_ground_joint" type="fixed">
+		<parent link="world"/>
+		<child link="ground"/>
+		<origin xyz="0 0 ${-ground_thickness/2}" rpy="0 0 0"/>
+	</joint>
+
 	<xacro:property name="board_h" value="0.6"/>
 	<xacro:property name="board_sX" value="2.5"/>
 	<xacro:property name="board_sY" value="1.5"/>