Updated models after icub-model-generator PR 49

[nunoguedelha]

Updated all models as per PR robotology/icub-models-generator#49. The updated elements in the URDF model are listed below :

• meshes filename paths
• the inertial sensors information moved from fake links to real <sensor> tags that are processed by iDynTree and respective <gazebo> tags processed by Gazebo
• Gazebo Yarp plugins definitions for the inertial sensors and the control boards.

The models iCubGenova03, iCubLisboa01 and iCubNancy01 are using DH parameters and are not generated from the CAD, so didn't get the inertial sensors updates.

The model iCubGenova04 has extra changes:

• an additional sensor head_mu_acc_1x1 matching the 3 1-axis accelerometers embedded in the IMU. This is required for getting the predicted accelerometers measurements from the IMU through the iDynTree interface.

[traversaro]

Thanks!

[nunoguedelha]

@traversaro @diegoferigo just adding a few requirement notes for sing these models on iCub:

1. add the following paths to the .bashrc (or .bash_profile on Macosx) GAZEBO_MODEL_PATH env. variable:

icub-gazebo-wholebody/models
icub-models
icub-models/iCub/robots

icub-gazebo-wholebody/models: this holds the models (e.g. “icub_on_feet”) defined through the model.config (model description, name, author,..) and the sdf file which includes a URI urdf model (e.g. iCubGenova04) and defines its initial position in the world.
Gazebo then has to find the selected URI model in the databases listed in GAZEBO_MODEL_PATH.
icub-models/iCub/robots: this holds the iCubGenova04 model. Again, as any gazebo model, it is defined through a model.config and an sdf file. Here, the sdf file has the link to the actual "model.urdf” file.
icub-models: this is where Gazebo finds the generic “iCub” model with all the .ini files (in /conf folder) and all the meshes (in /meshes folder). Otherwise we would need to have these folders (/conf and /meshes) in each robot model.

2. Set the URI urdf model in the sdf file associated to the model you want to use. For instance, for loading the “iCub (feet fixed)” model in Gazebo, the respective config and sdf files are: icub-gazebo-wholebody/models/icub_feet_fixed/model.config and icub-gazebo-wholebody/models/icub_feet_fixed/icub_feet_fixed.sdf.
   icub_feet_fixed.sdf is then defined as follows:

<?xml version='1.0'?>
<sdf version='1.4'>
  <model name="iCub">
    <include>
      <uri>model://iCubGenova04</uri>
      <pose>0.0 0 0.63 0 0 3.14</pose>
    </include>

    <joint name="fixed right to ground" type="revolute">
      <parent>world</parent>
      <child>ICUB_2-5_BB_SIM_MODEL::r_foot</child>
      ...
    </joint>
    <joint name="fixed left to ground" type="revolute">
      <parent>world</parent>
      <child>ICUB_2-5_BB_SIM_MODEL::l_foot</child>
      ...
    </joint>

  </model>
</sdf>

=> <uri>model://iCubGenova04</uri> selects the model ** iCubGenova04** in icub-models/iCub/robots.
=> Every referenced link starts with ICUB_2-5_BB_SIM_MODEL which is set in the <name> tag of icub-models/iCub/robots/iCubGenova04/model.urdf