commit 3c068fc166d662d1459610a56dc955f3bf22f7fe
Author: David V. Lu <davidvlu@gmail.com>
Date:   Sun Jul 2 16:07:37 2017 -0400

    Fix launch test

diff --git a/urdf_tutorial/launch/display.launch b/urdf_tutorial/launch/display.launch
index 959946a..66a429a 100644
--- a/urdf_tutorial/launch/display.launch
+++ b/urdf_tutorial/launch/display.launch
@@ -1,6 +1,6 @@
 <launch>
 
-  <arg name="model" />
+  <arg name="model" default="$(find urdf_tutorial)/urdf/01-myfirst.urdf"/>
   <arg name="gui" default="true" />
   <arg name="rvizconfig" default="$(find urdf_tutorial)/rviz/urdf.rviz" />