sdformat: Update to libsdformat 9.0 (SDFormat 1.7) (RobotLocomotion#1…

…2505)

This PR incorporates libsdformat 9.0, which supports the specification of
SDFormat 1.7.

Specifically, this incorporates pose frame semantics for SDFormat, which are
described in this proposal:
http://sdformat.org/tutorials?tut=pose_frame_semantics_proposal&cat=pose_semantics_docs
(source permalink: https://bit.ly/2ZSl1kH)

A brief summary of the changes from the proposal:
* Users may now specify poses relative to another frame using
`//pose/@relative_to`
  * Before, this was `//pose/@frame`, and was not described in the spec and
  only partially supported in Drake, but nowhere else.
  * Poses and frames within models cannot refer to the "world" frame.
* Users may now specify explicit frames, which will be exposed as
`MultibodyPlant` frames, and can be used within `//pose/@relative_to`.
  * Users can specify the attached-to fame using `//frame/@attached_to`.
  Before, this was specified using `//frame/pose/@frame`, and was only
  partially supported in Drake and nowhere else.
* All SDFormat models now have a canonical link, and all models have a model
frame attached to this canonical link.
  * For this reason, all models must have at least one link.
* `//joint/axis/xyz/@expressed_in` can be used to express an axis in a given
frame. `//joint/axis/use_parent_model_frame` has been removed in SDFormat 1.7,
but will be converted automatically from SDFormat 1.6 to 1.7.

(Note: The above paths are using XPath syntax.)

bindings/pydrake/test/parse_models_test.py

@@ -43,7 +43,10 @@ def test_available_runfiles(self):
             if model_relpath.startswith("external/sdformat/sdf"):
                 # These are schema files; do not load.
                 model_files.remove(model_file)
-        # Ensure that we have at least a certain number of models to check.
+        # We expect there to be dozens of files that should be available for
+        # parsing. Do a quick check to make sure we're in the right order of
+        # magnitude in order to prevent false test success based on changes
+        # that might lead to missing files.
         self.assertGreater(len(model_files), 40)
         # Parse each model file for testing.
         for model_file in model_files:

examples/kuka_iiwa_arm/models/table/extra_heavy_duty_table_surface_only_collision.sdf

@@ -303,7 +303,12 @@
     </link>
 
     <frame name='top_center'>
-      <pose frame='world'>0 0 0.7645 0 -0 0</pose>
+      <!--
+      TODO(eric.cousineau): @frame='link' is redundant, but not having it
+      causes RBT SDFormat parsing code to segfault. Remove this once RBT is
+      removed.
+      -->
+      <pose frame='link'>0 0 0.7645 0 -0 0</pose>
     </frame>
 
     <!--

manipulation/models/iiwa_description/sdf/iiwa14_no_collision.sdf

@@ -2,14 +2,17 @@
 <!--
 SDF automatically generated with: gz sdf -p /my_urdf.urdf > /my_sdf.sdf
 
-Later edited by hand to rename the base link and remove damping from the joints.
+Later edited by hand to:
+* rename the base link
+* remove damping from the joints
+* use pose frame semantics to reflect URDF pose values.
 -->
-<sdf version='1.6'>
+<sdf version='1.7'>
   <model name='iiwa14'>
     <link name='iiwa_link_0'>
-      <pose frame=''>0 0 0 0 -0 0</pose>
+      <pose>0 0 0 0 -0 0</pose>
       <inertial>
-        <pose frame=''>-0.1 0 0.07 0 -0 0</pose>
+        <pose>-0.1 0 0.07 0 -0 0</pose>
         <mass>5</mass>
         <inertia>
           <ixx>0.05</ixx>
@@ -21,7 +24,7 @@ Later edited by hand to rename the base link and remove damping from the joints.
         </inertia>
       </inertial>
       <visual name='iiwa_link_0_fixed_joint_lump__iiwa_link_0_visual'>
-        <pose frame=''>0 0 0 0 0 0</pose>
+        <pose>0 0 0 0 0 0</pose>
         <geometry>
           <mesh>
             <scale>1 1 1</scale>
@@ -38,9 +41,9 @@ Later edited by hand to rename the base link and remove damping from the joints.
     </link>
 
     <link name='iiwa_link_1'>
-      <pose frame=''>0 0 0.1575 0 -0 0</pose>
+      <pose relative_to="iiwa_joint_1">0 0 0 0 0 0</pose>
       <inertial>
-        <pose frame=''>0 -0.03 0.12 0 -0 0</pose>
+        <pose>0 -0.03 0.12 0 -0 0</pose>
         <mass>5.76</mass>
         <inertia>
           <ixx>0.033</ixx>
@@ -52,7 +55,7 @@ Later edited by hand to rename the base link and remove damping from the joints.
         </inertia>
       </inertial>
       <visual name='iiwa_link_1_visual'>
-        <pose frame=''>0 0 0 0 -0 0</pose>
+        <pose>0 0 0 0 -0 0</pose>
         <geometry>
           <mesh>
             <scale>1 1 1</scale>
@@ -68,6 +71,7 @@ Later edited by hand to rename the base link and remove damping from the joints.
       <self_collide>0</self_collide>
     </link>
     <joint name='iiwa_joint_1' type='revolute'>
+      <pose relative_to="iiwa_link_0">0 0 0.1575 0 0 0</pose>
       <child>iiwa_link_1</child>
       <parent>iiwa_link_0</parent>
       <axis>
@@ -84,13 +88,13 @@ Later edited by hand to rename the base link and remove damping from the joints.
           <spring_reference>0</spring_reference>
           <spring_stiffness>0</spring_stiffness>
         </dynamics>
-        <use_parent_model_frame>1</use_parent_model_frame>
       </axis>
     </joint>
+    <!-- SDFormat 1.7 -->
     <link name='iiwa_link_2'>
-      <pose frame=''>0 0 0.36 1.5708 -0 -3.14159</pose>
+      <pose relative_to="iiwa_joint_2">0 0 0 0 0 0</pose>
       <inertial>
-        <pose frame=''>0.0003 0.059 0.042 0 -0 0</pose>
+        <pose>0.0003 0.059 0.042 0 -0 0</pose>
         <mass>6.35</mass>
         <inertia>
           <ixx>0.0305</ixx>
@@ -102,7 +106,7 @@ Later edited by hand to rename the base link and remove damping from the joints.
         </inertia>
       </inertial>
       <visual name='iiwa_link_2_visual_grey'>
-        <pose frame=''>0 0 0 0 -0 0</pose>
+        <pose>0 0 0 0 -0 0</pose>
         <geometry>
           <mesh>
             <scale>1 1 1</scale>
@@ -114,7 +118,7 @@ Later edited by hand to rename the base link and remove damping from the joints.
         </material>
       </visual>
       <visual name='iiwa_link_2_visual_orange'>
-        <pose frame=''>0 0 0 0 -0 0</pose>
+        <pose>0 0 0 0 -0 0</pose>
         <geometry>
           <mesh>
             <scale>1 1 1</scale>
@@ -130,10 +134,13 @@ Later edited by hand to rename the base link and remove damping from the joints.
       <self_collide>0</self_collide>
     </link>
     <joint name='iiwa_joint_2' type='revolute'>
+      <pose relative_to="iiwa_link_1">
+        0 0 0.2025 1.570796326794897 0 3.141592653589793
+      </pose>
       <child>iiwa_link_2</child>
       <parent>iiwa_link_1</parent>
       <axis>
-        <xyz>-0 1 0</xyz>
+        <xyz>0 0 1</xyz>
         <limit>
           <lower>-2.0944</lower>
           <upper>2.0944</upper>
@@ -146,13 +153,12 @@ Later edited by hand to rename the base link and remove damping from the joints.
           <spring_reference>0</spring_reference>
           <spring_stiffness>0</spring_stiffness>
         </dynamics>
-        <use_parent_model_frame>1</use_parent_model_frame>
       </axis>
     </joint>
     <link name='iiwa_link_3'>
-      <pose frame=''>0 -0 0.5645 0 0 0</pose>
+      <pose relative_to="iiwa_joint_3">0 0 0 0 0 0</pose>
       <inertial>
-        <pose frame=''>0 0.03 0.13 0 -0 0</pose>
+        <pose>0 0.03 0.13 0 -0 0</pose>
         <mass>3.5</mass>
         <inertia>
           <ixx>0.025</ixx>
@@ -164,7 +170,7 @@ Later edited by hand to rename the base link and remove damping from the joints.
         </inertia>
       </inertial>
       <visual name='iiwa_link_3_visual'>
-        <pose frame=''>0 0 0 0 -0 0</pose>
+        <pose>0 0 0 0 -0 0</pose>
         <geometry>
           <mesh>
             <scale>1 1 1</scale>
@@ -176,7 +182,7 @@ Later edited by hand to rename the base link and remove damping from the joints.
         </material>
       </visual>
       <visual name='iiwa_link_3_visual_band'>
-        <pose frame=''>0 0 0 0 -0 0</pose>
+        <pose>0 0 0 0 -0 0</pose>
         <geometry>
           <mesh>
             <scale>1 1 1</scale>
@@ -188,7 +194,7 @@ Later edited by hand to rename the base link and remove damping from the joints.
         </material>
       </visual>
       <visual name='iiwa_link_3_visual_kuka'>
-        <pose frame=''>0 0 0 0 -0 0</pose>
+        <pose>0 0 0 0 -0 0</pose>
         <geometry>
           <mesh>
             <scale>1 1 1</scale>
@@ -204,6 +210,7 @@ Later edited by hand to rename the base link and remove damping from the joints.
       <self_collide>0</self_collide>
     </link>
     <joint name='iiwa_joint_3' type='revolute'>
+      <pose relative_to="iiwa_link_2">0 0.2045 0 1.570796326794897 0 3.141592653589793</pose>
       <child>iiwa_link_3</child>
       <parent>iiwa_link_2</parent>
       <axis>
@@ -220,13 +227,12 @@ Later edited by hand to rename the base link and remove damping from the joints.
           <spring_reference>0</spring_reference>
           <spring_stiffness>0</spring_stiffness>
         </dynamics>
-        <use_parent_model_frame>1</use_parent_model_frame>
       </axis>
     </joint>
     <link name='iiwa_link_4'>
-      <pose frame=''>0 -0 0.78 1.5708 0 0</pose>
+      <pose relative_to="iiwa_joint_4">0 0 0 0 0 0</pose>
       <inertial>
-        <pose frame=''>0 0.067 0.034 0 -0 0</pose>
+        <pose>0 0.067 0.034 0 -0 0</pose>
         <mass>3.5</mass>
         <inertia>
           <ixx>0.017</ixx>
@@ -238,7 +244,7 @@ Later edited by hand to rename the base link and remove damping from the joints.
         </inertia>
       </inertial>
       <visual name='iiwa_link_4_visual_grey'>
-        <pose frame=''>0 0 0 0 -0 0</pose>
+        <pose>0 0 0 0 -0 0</pose>
         <geometry>
           <mesh>
             <scale>1 1 1</scale>
@@ -250,7 +256,7 @@ Later edited by hand to rename the base link and remove damping from the joints.
         </material>
       </visual>
       <visual name='iiwa_link_4_visual_orange'>
-        <pose frame=''>0 0 0 0 -0 0</pose>
+        <pose>0 0 0 0 -0 0</pose>
         <geometry>
           <mesh>
             <scale>1 1 1</scale>
@@ -266,10 +272,11 @@ Later edited by hand to rename the base link and remove damping from the joints.
       <self_collide>0</self_collide>
     </link>
     <joint name='iiwa_joint_4' type='revolute'>
+      <pose relative_to="iiwa_link_3">0 0 0.2155 1.570796326794897 0 0</pose>
       <child>iiwa_link_4</child>
       <parent>iiwa_link_3</parent>
       <axis>
-        <xyz>0 -1 0</xyz>
+        <xyz>0 0 1</xyz>
         <limit>
           <lower>-2.0944</lower>
           <upper>2.0944</upper>
@@ -282,13 +289,12 @@ Later edited by hand to rename the base link and remove damping from the joints.
           <spring_reference>0</spring_reference>
           <spring_stiffness>0</spring_stiffness>
         </dynamics>
-        <use_parent_model_frame>1</use_parent_model_frame>
       </axis>
     </joint>
     <link name='iiwa_link_5'>
-      <pose frame=''>0 -0 0.9645 0 -0 -3.14159</pose>
+      <pose relative_to="iiwa_joint_5">0 0 0 0 0 0</pose>
       <inertial>
-        <pose frame=''>0.0001 0.021 0.076 0 -0 0</pose>
+        <pose>0.0001 0.021 0.076 0 -0 0</pose>
         <mass>3.5</mass>
         <inertia>
           <ixx>0.01</ixx>
@@ -300,7 +306,7 @@ Later edited by hand to rename the base link and remove damping from the joints.
         </inertia>
       </inertial>
       <visual name='iiwa_link_5_visual'>
-        <pose frame=''>0 0 0 0 -0 0</pose>
+        <pose>0 0 0 0 -0 0</pose>
         <geometry>
           <mesh>
             <scale>1 1 1</scale>
@@ -312,7 +318,7 @@ Later edited by hand to rename the base link and remove damping from the joints.
         </material>
       </visual>
       <visual name='iiwa_link_5_visual_band'>
-        <pose frame=''>0 0 0 0 -0 0</pose>
+        <pose>0 0 0 0 -0 0</pose>
         <geometry>
           <mesh>
             <scale>1 1 1</scale>
@@ -324,7 +330,7 @@ Later edited by hand to rename the base link and remove damping from the joints.
         </material>
       </visual>
       <visual name='iiwa_link_5_visual_kuka'>
-        <pose frame=''>0 0 0 0 -0 0</pose>
+        <pose>0 0 0 0 -0 0</pose>
         <geometry>
           <mesh>
             <scale>1 1 1</scale>
@@ -340,6 +346,7 @@ Later edited by hand to rename the base link and remove damping from the joints.
       <self_collide>0</self_collide>
     </link>
     <joint name='iiwa_joint_5' type='revolute'>
+      <pose relative_to="iiwa_link_4">0 0.1845 0 -1.570796326794897 3.141592653589793 0</pose>
       <child>iiwa_link_5</child>
       <parent>iiwa_link_4</parent>
       <axis>
@@ -356,13 +363,12 @@ Later edited by hand to rename the base link and remove damping from the joints.
           <spring_reference>0</spring_reference>
           <spring_stiffness>0</spring_stiffness>
         </dynamics>
-        <use_parent_model_frame>1</use_parent_model_frame>
       </axis>
     </joint>
     <link name='iiwa_link_6'>
-      <pose frame=''>0 0 1.18 1.5708 -0 -3.14159</pose>
+      <pose relative_to="iiwa_joint_6">0 0 0 0 0 0</pose>
       <inertial>
-        <pose frame=''>0 0.0006 0.0004 0 -0 0</pose>
+        <pose>0 0.0006 0.0004 0 -0 0</pose>
         <mass>1.8</mass>
         <inertia>
           <ixx>0.0049</ixx>
@@ -374,7 +380,7 @@ Later edited by hand to rename the base link and remove damping from the joints.
         </inertia>
       </inertial>
       <visual name='iiwa_link_6_visual_grey'>
-        <pose frame=''>0 0 0 0 -0 0</pose>
+        <pose>0 0 0 0 -0 0</pose>
         <geometry>
           <mesh>
             <scale>1 1 1</scale>
@@ -386,7 +392,7 @@ Later edited by hand to rename the base link and remove damping from the joints.
         </material>
       </visual>
       <visual name='iiwa_link_6_visual_orange'>
-        <pose frame=''>0 0 0 0 -0 0</pose>
+        <pose>0 0 0 0 -0 0</pose>
         <geometry>
           <mesh>
             <scale>1 1 1</scale>
@@ -402,10 +408,11 @@ Later edited by hand to rename the base link and remove damping from the joints.
       <self_collide>0</self_collide>
     </link>
     <joint name='iiwa_joint_6' type='revolute'>
+      <pose relative_to="iiwa_link_5">0 0 0.2155 1.570796326794897 0 0</pose>
       <child>iiwa_link_6</child>
       <parent>iiwa_link_5</parent>
       <axis>
-        <xyz>-0 1 -0</xyz>
+        <xyz>0 0 1</xyz>
         <limit>
           <lower>-2.0944</lower>
           <upper>2.0944</upper>
@@ -418,13 +425,12 @@ Later edited by hand to rename the base link and remove damping from the joints.
           <spring_reference>0</spring_reference>
           <spring_stiffness>0</spring_stiffness>
         </dynamics>
-        <use_parent_model_frame>1</use_parent_model_frame>
       </axis>
     </joint>
     <link name='iiwa_link_7'>
-      <pose frame=''>0 0 1.261 0 0 0</pose>
+      <pose relative_to="iiwa_joint_7">0 0 0 0 0 0</pose>
       <inertial>
-        <pose frame=''>0 0 0.02 0 -0 0</pose>
+        <pose>0 0 0.02 0 -0 0</pose>
         <mass>1.2</mass>
         <inertia>
           <ixx>0.001</ixx>
@@ -436,7 +442,7 @@ Later edited by hand to rename the base link and remove damping from the joints.
         </inertia>
       </inertial>
       <visual name='iiwa_link_7_visual'>
-        <pose frame=''>0 0 0 0 -0 0</pose>
+        <pose>0 0 0 0 -0 0</pose>
         <geometry>
           <mesh>
             <scale>1 1 1</scale>
@@ -452,6 +458,9 @@ Later edited by hand to rename the base link and remove damping from the joints.
       <self_collide>0</self_collide>
     </link>
     <joint name='iiwa_joint_7' type='revolute'>
+      <pose relative_to="iiwa_link_6">
+        0 0.081 0 -1.570796326794897 3.141592653589793 0
+      </pose>
       <child>iiwa_link_7</child>
       <parent>iiwa_link_6</parent>
       <axis>
@@ -468,7 +477,6 @@ Later edited by hand to rename the base link and remove damping from the joints.
           <spring_reference>0</spring_reference>
           <spring_stiffness>0</spring_stiffness>
         </dynamics>
-        <use_parent_model_frame>1</use_parent_model_frame>
       </axis>
     </joint>
     <static>0</static>

multibody/inverse_kinematics/test/position_constraint_test.cc

@@ -85,8 +85,10 @@ TEST_F(IiwaKinematicConstraintTest, PositionConstraint) {
     dq(i, 1) = std::sin(i + 0.2);
   }
   /* tolerance for checking numerical gradient vs analytical gradient. The
-   * numerical gradient is only accurate up to 2E-7 */
-  const double gradient_tol = 2E-7;
+   * numerical gradient is only accurate up to 4E-7 */
+  // N.B. Using libsdformat9 with pose frame semantics requires an increase in
+  // tolerance from 2E-7 to 4E-7.
+  const double gradient_tol = 4E-7;
   TestKinematicConstraintEval(constraint, constraint_from_autodiff, q, dq,
                               gradient_tol);
 }