Add effort command interface to all joints (backport of #302) (#351)

Author: mergify[bot]

urdf/inc/ur_joint_control.xacro

@@ -8,6 +8,7 @@
     <joint name="${tf_prefix}shoulder_pan_joint">
       <command_interface name="position"/>
       <command_interface name="velocity"/>
+      <command_interface name="effort"/>
       <state_interface name="position">
         <!-- initial position for the mock system and simulation -->
         <param name="initial_value">${initial_positions['shoulder_pan_joint']}</param>
@@ -22,6 +23,7 @@
     <joint name="${tf_prefix}shoulder_lift_joint">
       <command_interface name="position"/>
       <command_interface name="velocity"/>
+      <command_interface name="effort"/>
       <state_interface name="position">
         <!-- initial position for the mock system and simulation -->
         <param name="initial_value">${initial_positions['shoulder_lift_joint']}</param>
@@ -36,6 +38,7 @@
     <joint name="${tf_prefix}elbow_joint">
       <command_interface name="position"/>
       <command_interface name="velocity"/>
+      <command_interface name="effort"/>
       <state_interface name="position">
         <!-- initial position for the mock system and simulation -->
         <param name="initial_value">${initial_positions['elbow_joint']}</param>
@@ -50,6 +53,7 @@
     <joint name="${tf_prefix}wrist_1_joint">
       <command_interface name="position"/>
       <command_interface name="velocity"/>
+      <command_interface name="effort"/>
       <state_interface name="position">
         <!-- initial position for the mock system and simulation -->
         <param name="initial_value">${initial_positions['wrist_1_joint']}</param>
@@ -64,6 +68,7 @@
     <joint name="${tf_prefix}wrist_2_joint">
       <command_interface name="position"/>
       <command_interface name="velocity"/>
+      <command_interface name="effort"/>
       <state_interface name="position">
         <!-- initial position for the mock system and simulation -->
         <param name="initial_value">${initial_positions['wrist_2_joint']}</param>
@@ -78,6 +83,7 @@
     <joint name="${tf_prefix}wrist_3_joint">
       <command_interface name="position"/>
       <command_interface name="velocity"/>
+      <command_interface name="effort"/>
       <state_interface name="position">
         <!-- initial position for the mock system and simulation -->
         <param name="initial_value">${initial_positions['wrist_3_joint']}</param>