Add a sensor for the TCP pose (#197)

* Add a sensor for the TCP pose

* Use quaternion notation for rotation state interfaces

(cherry picked from commit ea0c6b5)

# Conflicts:
#	urdf/inc/ur_sensors.xacro

urdf/inc/ur_sensors.xacro

@@ -0,0 +1,22 @@
+<?xml version="1.0"?>
+<robot xmlns:xacro="http://www.ros.org/wiki/xacro">
+  <xacro:macro name="ur_sensors" params="tf_prefix">
+    <sensor name="${tf_prefix}tcp_fts_sensor">
+      <state_interface name="force.x"/>
+      <state_interface name="force.y"/>
+      <state_interface name="force.z"/>
+      <state_interface name="torque.x"/>
+      <state_interface name="torque.y"/>
+      <state_interface name="torque.z"/>
+    </sensor>
+    <sensor name="${tf_prefix}tcp_pose">
+      <state_interface name="position.x"/>
+      <state_interface name="position.y"/>
+      <state_interface name="position.z"/>
+      <state_interface name="orientation.x"/>
+      <state_interface name="orientation.y"/>
+      <state_interface name="orientation.z"/>
+      <state_interface name="orientation.w"/>
+    </sensor>
+  </xacro:macro>
+</robot>