message: Define hand_tcp frame
  ... in the center between and aligned with the fingers
diff: </geometry>
  </collision>
  </link>
  + <!-- Define the hand_tcp frame -->
  + <link name="${ns}_hand_tcp" />
  + <joint name="${ns}_hand_tcp_joint" type="fixed">
  + <origin xyz="0 0 0.1034" rpy="0 0 0" />
  + <parent link="${ns}_hand" />
  + <child link="${ns}_hand_tcp" />
  + </joint>
  <link name="${ns}_leftfinger">
  <visual>
  <geometry>
  