Migration.md

Migration Guide for SDFormat Specification

This document contains information about migrating between different versions of the SDFormat specification. The SDFormat specification version number is specified in the version attribute of the sdf element (1.4, 1.5, 1.6, etc.) and is distinct from sdformat library version (2.3, 3.0, 4.0, etc.).

Note on backward compatibility

There are *.convert files that allow old sdf files to be migrated forward programmatically. This document aims to contain similar information to those files but with improved human-readability..

libsdformat 14.x to 15.x

Additions

1. New SDFormat specification version 1.12
   • Details about the 1.11 to 1.12 transition are explained below in this same document

Modifications

1. Behavior change of Param::Get<bool>
   • Previously when a Param was set from a string, the Get<bool> method would always return true, and the value would be true if the lowercase string value matched "1" or "true" and false otherwise. Now, the Get<bool> method returns true only if the lowercase value string matches "0", "1", "true", or "false" and returns false otherwise.

Deprecations

• sdf/Camera.hh:
  • The //sensor/camera/optical_frame_id SDF element and corresponding functions in the Camera DOM class are deprecated. Please specify camera frame using the //sensor/frame_id SDF element instead.
  • Deprecation: std::string OpticalFrameId() const
  • Replacement: std::string Sensor::FrameId() const
  • Deprecation: void SetOpticalFrameId(const std::string &)
  • Replacement: void Sensor::SetFrameId(const std::string &)

Removals

• sdf/Joint.hh:

  • const std::string &ChildLinkName() const (use ChildName() instead)
  • const std::string &ParentLinkName() const (use ParentName() instead)
  • void SetChildLinkName(const std::string &) (use SetChildName() instead)
  • void SetParentLinkName(const std::string &) (use SetParentName() instead)

• sdf/SDFImpl.hh:

  • void Root(const ElementPtr) (use SetRoot(const ElementPtr) instead)

• sdf/Types.hh:

  • const std::string &kSdfScopeDelimiter (use kScopeDelimiter instead)
  • const std::string &SdfScopeDelimiter() (use kScopeDelimiter instead)

• sdf/parser.hh:

  • bool checkJointParentChildLinkNames(const sdf::Root *) (use checkJointParentChildNames(const sdf::Root *) instead)

libsdformat 13.x to 14.x

Additions

1. New SDFormat specification version 1.11
   • Details about the 1.10 to 1.11 transition are explained below in this same document

Modifications

1. The default camera lens intrinsics skew value in the Camera DOM class changed from 1 to 0 to match the SDF specification.

2. World class only renames frames with name collisions if original file version is 1.6 or earlier. Name collisions in newer files will cause DUPLICATE_NAME errors, which now matches the behavior of the Model class.

3. Python is now required to build libsdformat instead of Ruby.

4. sdf/ParserConfig.hh The following new functions were added to support automatic calculation of moments of inertia.

   • ConfigureResolveAutoInertials CalculateInertialConfiguration() const
   • void SetCalculateInertialConfiguration(ConfigureResolveAutoInertials)
   • void RegisterCustomInertiaCalc(CustomInertiaCalculator)
   • const CustomInertiaCalculator &CustomInertiaCalc() const

libsdformat 12.x to 13.x

Additions

1. New SDFormat specification version 1.10
   • Details about the 1.9 to 1.10 transition are explained below in this same document

Modifications

1. ParserConfig defaults to WARN instead of LOG when parsing unrecognized elements.
2. Updated search order for sdf::findFile() making local path (current directory) the first to be searched.

Deprecations

• The ignition namespace is deprecated and will be removed in future versions. Use gz instead.

• Header files under ignition/... are deprecated and will be removed in future versions. Use gz/... instead.

• sdf/Types.hh: The Inertia class has been deprecated. Please use the  Inertial class in the gz-math library.

• sdf/Joint.hh:

  • Deprecation: const std::string &ChildLinkName() const
  • Replacement: const std::string &ChildName() const
  • Deprecation: const std::string &ParentLinkName() const
  • Replacement: const std::string &ParentName() const
  • Deprecation: void SetChildLinkName(const std::string &)
  • Replacement: void SetChildName(const std::string &)
  • Deprecation: void SetParentLinkName(const std::string &)
  • Replacement: void SetParentName(const std::string &)

• sdf/parser.hh:

  • Deprecation: bool checkJointParentChildLinkNames(const sdf::Root *)
  • Replacement: bool checkJointParentChildNames(const sdf::Root *)

• sdf/SDFImpl.hh:

  • Deprecation: void Root(sdf::ElementPtr)
  • Replacement: void SetRoot(sdf::ElementPtr)

Removals

• sdf/InterfaceElements.hh: The deprecated data members from the NestedInclude class have been removed. Instead use the corresponding member functions.

• sdf/Types.hh: The SDF_DEPRECATED and SDF_SUPPRESS_* macros have been removed in favor of GZ_DEPRECATED and GZ_UTILS_WARN_*.

libsdformat 12.5.0 to 12.6.0

Modifications

1. USD component now is living in https://github.com/gazebosim/gz-usd as an independent package.

2. URDF parser now properly transforms poses for lights, projectors and sensors from gazebo extension tags that are moved to a new link during fixed joint reduction.

   • pull request 1114

libsdformat 11.x to 12.0

An error is now emitted instead of a warning for a file containing more than one root level model, actor or light.

Additions

1. New SDFormat specification version 1.9

   • Details about the 1.8 to 1.9 transition are explained below in this same document

2. sdf/Camera.hh The following new functions were added for segmentation cameras

   • void SetHasSegmentationType(bool)
   • bool HasSegmentationType() const
   • const std::string &SegmentationType() const
   • void SetSegmentationType(const std::string &)
   • void SetHasBoundingBoxType(bool)
   • bool HasBoundingBoxType() const
   • const std::string &BoundingBoxType() const
   • void SetBoundingBoxType(const std::string &)

3. sdf/Elementh.hh

   • const Param_V &GetAttributes() const

4. sdf/Error.hh

   • void SetFilePath(const std::string &)
   • void SetLineNumber(int)

5. sdf/ForceTorque.hh

   • const Noise &ForceXNoise() const
   • void SetForceXNoise(const Noise &)
   • const Noise &ForceYNoise() const
   • void SetForceYNoise(const Noise &)
   • const Noise &ForceZNoise() const
   • void SetForceZNoise(const Noise &)
   • const Noise &TorqueXNoise() const
   • void SetTorqueXNoise(const Noise &)
   • const Noise &TorqueYNoise() const
   • void SetTorqueYNoise(const Noise &)
   • const Noise &TorqueZNoise() const
   • void SetTorqueZNoise(const Noise &)

6. sdf/InterfaceElements.hh sdf::NestedInclude has the following new methods

   • const std::string &Uri() const
   • void SetUri(const std::string &)
   • const std::string &ResolvedFileName() const
   • void SetResolvedFileName(const std::string &)
   • const std::string &AbsoluteParentName() const
   • void SetAbsoluteParentName(const std::string &)
   • const std::optionalstd::string &LocalModelName() const
   • void SetLocalModelName(const std::string &)
   • const std::optional &IsStatic() const
   • void SetIsStatic(bool)
   • const std::optionalgz::math::Pose3d &IncludeRawPose() const
   • void SetIncludeRawPose(const gz::math::Pose3d &includeRawPose)
   • const std::optionalstd::string &IncludePoseRelativeTo() const
   • void SetIncludePoseRelativeTo(const std::string &)
   • const std::optionalstd::string &PlacementFrame() const
   • void SetPlacementFrame(const std::string &)
   • sdf::ElementPtr IncludeElement() const
   • void SetIncludeElement(sdf::ElementPtr)

7. sdf/Param.hh:

   • ElementPtr GetParentElement() const;
   • bool SetParentElement(ElementPtr);
   • bool Reparse();
   • bool IgnoresParentElementAttribute() const;

8. sdf/World.hh:

   • const gz::math::SphericalCoordinates * SphericalCoordinates() const;
   • void SetSphericalCoordinates(const gz::math::SphericalCoordinates &);

Modifications

1. sdf/Element.hh: The following methods now have an additional parameter of type PrintConfig with a default value

   • void PrintValues(std::string, const PrintConfig &_config = PrintConfig()) const
   • void PrintValues(const std::string, bool, bool, const PrintConfig &_config = PrintConfig()) const
   • std::string ToString(const std::string &, const PrintConfig &_config = PrintConfig()) const
   • std::string ToString(const std::string &, bool, bool ,const PrintConfig &_config = PrintConfig()) const

2. sdf/Param.hh: The following methods now have an additional parameter of type PrintConfig with a default value

   • std::string GetAsString(const PrintConfig &_config = PrintConfig()) const
   • std::string GetDefaultAsString(const PrintConfig &_config = PrintConfig()) const
   • std::optionalstd::string GetMinValueAsString(const PrintConfig &_config = PrintConfig()) const
   • std::optionalstd::string GetMaxValueAsString(const PrintConfig &_config = PrintConfig()) const

   The following now has an additional bool parameter

   • bool SetFromString(const std::string &, bool _ignoreParentAttributes);

3. sdf/SDFImpl.hh: The following methods now have an additional parameter of type PrintConfig with a default value

   • void PrintValues(const PrintConfig &_config = PrintConfig())
   • std::string ToString(const PrintConfig &_config = PrintConfig()) const

4. The string literals used to indicate non-file sources have been changed to <data-string> and <urdf-string> for SDFormat and URDF source respectively. Users are encouraged to use the constants kSdfStringSource and kUrdfStringSource instead of hard-coding the string literals.

Removals

The following deprecated methods and classes have been removed.

1. sdf/Element.hh

   • void SetInclude(const std::string)
   • std::string GetInclude() const

2. sdf/Types.hh

   • sdf::Color class

3. sdf/JointAxis.hh

   • double InitialPosition() const
   • void SetInitialPosition(const double)

4. sdf/Root.hh:

   • const sdf::Model *ModelByIndex()
   • uint64_t ModelCount()
   • bool ModelNameExists(const std::string &_name) const
   • const sdf::Light *LightByIndex()
   • uint64_t LightCount()
   • bool LightNameExists(const std::string &_name) const
   • const sdf::Actor *ActorByIndex()
   • uint64_t ActorCount()
   • bool ActorNameExists(const std::string &_name) const

Deprecations

1. sdf/InterfaceElements.hh: The struct NestedInclude has been converted to a class. Accessing data members directly is deprecated. Instead use the corresponding member functions.

libsdformat 11.1.0 to 11.2.0

ABI was broken for sdf::Element, and restored on version 11.2.1.

libsdformat 11.0.0 to 11.x.x

Additions

1. sdf/Console.hh Add functions to retrieve message stream objects. These can be useful for redirecting the console output to other streams.

   • ConsoleStream &GetMsgStream()
   • ConsoleStream &GetLogStream()

2. sdf/ParserConfig.hh:

   • void SetDeprecatedElementsPolicy(EnforcementPolicy _policy)
   • void ResetDeprecatedElementsPolicy()
   • EnforcementPolicy DeprecatedElementsPolicy() const

3. test/test_utils.hh:

   • ScopeExit: A utility struct that calls a function when going out of scope.
   • RedirectConsoleStream: A utility class used for redirecting the output of sdferr, sdfwarn, etc to a more convenient stream object like a std::stringstream for testing purposes.

libsdformat 10.x to 11.0

Additions

1. sdf/ParserConfig.hh A class that contains configuration options for the libsdformat parser.

2. • Depend on ignition-utils1 for the ImplPtr and UniqueImplPtr.
   • Pull request 474

3. sdf/Joint.hh

   • Errors ResolveChildLink(std::string&) const
   • Errors ResolveParentLink(std::string&) const

4. sdf/Model.hh:

   • std::pair<const Link *, std::string> CanonicalLinkAndRelativeName() const;

5. sdf/Root.hh sdf::Root elements can now only contain one of either Model, Light or Actor since multiple items would conflict with overrides specified in an tag.

   • const sdf::Model *Model();
   • const sdf::Light *Light();
   • const sdf::Actor *Actor();

Modifications

1. sdf/Model.hh: the following methods now accept nested names relative to the model's scope that can begin with a sequence of nested model names separated by :: and may end with the name of an object of the specified type.

   • const Frame *FrameByName(const std::string &) const
   • const Joint *JointByName(const std::string &) const
   • const Link *LinkByName(const std::string &) const
   • bool FrameNameExists(const std::string &) const
   • bool JointNameExists(const std::string &) const
   • bool LinkNameExists(const std::string &) const

2. sdf/Heightmap.hh: sampling now defaults to 1 instead of 2.

Deprecations

1. src/Root.hh: The following methods have been deprecated in favor of the new methods. For now the behavior is unchanged, but Root elements should only contain one or none of Model/Light/Actor.
   • const sdf::Model *ModelByIndex();
   • uint64_t ModelCount();
   • bool ModelNameExists(const std::string &_name) const;
   • const sdf::Light *LightByIndex();
   • uint64_t LightCount();
   • bool LightNameExists(const std::string &_name) const;
   • const sdf::Actor *ActorByIndex();
   • uint64_t ActorCount();
   • bool ActorNameExists(const std::string &_name) const;

libsdformat 10.2.0 to 10.x.x

Modifications

1. Fixed Atmosphere DOM class's temperature default value. Changed from -0.065 to -0.0065.

   • Pull request 482

2. Fixed parsing of <sensor><pose> tags on lumped links when converting from URDF.

   • Pull request 525

libsdformat 9.x to 10.0

Modifications

1. Axis vectors specified in are normalized if their norm is greater than 0. A vector with 0 norm generates an error

   • Pull request 312
2. • Depend on tinyxml2 instead of tinyxml for XML parsing.
   • Pull request 264
3. • Minimum/maximum values specified in SDFormat description files are now enforced
   • Pull request 303
4. • Parsing of bad values generates an error
   • Pull request 244

Deletions

1. • Removed the parser_urdf.hh header file and its URDF2SDF class
   • Pull request 276
2. • Removed the deprecated Pose(), SetPose(), and *PoseFrame() API's in all DOM classes:
   • const gz::math::Pose3d &Pose()
   • void SetPose(const gz::math::Pose3d &)
   • const std::string &PoseFrame()
   • void SetPoseFrame(const std::string &)
3. • Removed deprecated functions from sdf/JointAxis.hh:
   • bool UseParentModelFrame()
   • void SetUseParentModelFrame(bool)

Additions

1. sdf/Element.hh

   • void AddValue(const std::string &, const std::string &, bool, const std::string &, const std::string &, const std::string &)

2. sdf/Param.hh

   • Param(const std::string &, const std::string &e, const std::string &, bool, const std::string &, const std::string &, const std::string &)
   • std::optionalstd::string GetMinValueAsString() const;
   • std::optionalstd::string GetMaxValueAsString() const;
   • bool ValidateValue() const;

libsdformat 9.8.0 to 9.9.0

Additions

1. sdf/Camera.hh
   • Get/Set functions for Camera projection matrix parameters.

Modifications

1. URDF parser now properly transforms poses for lights, projectors and sensors from gazebo extension tags that are moved to a new link during fixed joint reduction.
   • pull request 1114

libsdformat 9.4 to 9.5

Additions

1. sdf/Element.hh
   • sdf::ElementPtr FindElement() const

libsdformat 9.3 to 9.4

Modifications

1. camera.sdf
   • Reduce minimum value of //camera/clip/far

Deprecations

1. Fix spelling of supported shader types in //material/shader/@type
   • normal_map_objectspace replaced by normal_map_object_space
   • normal_map_tangentspace replaced by normal_map_tangent_space
   • pull request 383

libsdformat 9.0 to 9.3

Additions

1. sdf/Model.hh
   • uint64_t ModelCount() const
   • const Model *ModelByIndex(const uint64_t) const
   • const Model *ModelByName(const std::string &) const
   • bool ModelNameExists(const std::string &) const

Modifications

1. Permit models without links if they contain a nested canonical link.
   • pull request 341

SDFormat 8.x to 9.0

Additions

1. sdf/Collision.hh

   • sdf::SemanticPose SemanticPose() const

2. sdf/Element.hh

   • void Clear()
   • const std::string &OriginalVersion() const
   • void SetOriginalVersion(const std::string &)

3. sdf/Frame.hh: DOM class for frames in the model or world.

   • Errors ResolveAttachedToBody(std::string&) const
   • sdf::SemanticPose SemanticPose() const

4. sdf/Joint.hh

   • sdf::SemanticPose SemanticPose() const

5. sdf/JointAxis.hh

   • Errors ResolveXyz(gz::math::Vector3d &, const std::string &) const

6. sdf/Light.hh

   • sdf::SemanticPose SemanticPose() const

7. sdf/Link.hh

   • sdf::SemanticPose SemanticPose() const

8. sdf/Model.hh

   • uint64_t FrameCount() const
   • const Frame *FrameByIndex(const uint64_t) const
   • const Frame *FrameByName(const std::string &) const
   • bool FrameNameExists(const std::string &) const
   • sdf::SemanticPose SemanticPose() const

9. sdf/SDFImpl.hh

   • void Clear()
   • const std::string &OriginalVersion() const
   • void SetOriginalVersion(const std::string &)

10. sdf/SemanticPose.hh: Helper class for resolving poses of DOM objects.

11. sdf/Sensor.hh

    • sdf::SemanticPose SemanticPose() const

12. sdf/Visual.hh

    • sdf::SemanticPose SemanticPose() const

13. sdf/World.hh

    • uint64_t FrameCount() const
    • const Frame *FrameByIndex(const uint64_t) const
    • const Frame *FrameByName(const std::string &) const
    • bool FrameNameExists(const std::string &) const
    • const Model *ModelByName(const std::string &) const

14. sdf/parser.hh

    • bool checkCanonicalLinkNames(sdf::Root*)
    • bool checkFrameAttachedToGraph(sdf::Root*)
    • bool checkFrameAttachedToNames(sdf::Root*)
    • bool checkJointParentChildLinkNames(sdf::Root*)
    • bool checkPoseRelativeToGraph(sdf::Root*)
    • bool recursiveSameTypeUniqueNames(sdf::ElementPtr)
    • bool recursiveSiblingUniqueNames(sdf::ElementPtr)
    • bool shouldValidateElement(sdf::ElementPtr)

Deprecations

1. sdf/parser_urdf.hh

   • Deprecation: URDF2SDF
   • Replacement: None. Use the functions sdf::readFile or sdf::readString, which automatically convert URDF to SDFormat.

2. All DOM classes with Pose() and PoseFrame() API's:

   • Deprecation: const gz::math::Pose3d &Pose()
   • Replacement: const gz::math::Pose3d &RawPose()
   • Deprecation: const std::string &PoseFrame()
   • Replacement: const std::string &PoseRelativeTo()
   • Deprecation: void SetPose(const gz::math::Pose3d &)
   • Replacement: void SetRawPose(const gz::math::Pose3d &)
   • Deprecation: void SetPoseFrame(const std::string &)
   • Replacement: void SetPoseRelativeTo(const std::string &)

3. sdf/JointAxis.hh

   • Deprecation: bool UseParentModelFrame()
   • Replacement: const std::string &XyzExpressedIn()
   • Deprecation: void SetUseParentModelFrame(bool)
   • Replacement: void SetXyzExpressedIn(const std::string &)

SDFormat 8.0 to 8.1

Modifications

1. • Change installation path of SDF description files to allow side-by-side installation.
   • {prefix}/share/sdformat/1.*/*.sdf -> {prefix}/share/sdformat8/1.*/*.sdf
   • BitBucket pull request 538

SDFormat 5.x to 6.x

Additions

1. sdf/parser.hh
   • bool recursiveSameTypeUniqueNames(sdf::ElementPtr)

Deprecations

1. sdf/Types.hh
   • Deprecated: sdf::Color class
   • Replacement: gz::math::Color class

SDFormat 4.x to 5.x

Deletions

1. Removed the following functions from parser.hh
   • bool initDoc(TiXmlDocument *_xmlDoc, SDFPtr _sdf);
   • bool initDoc(TiXmlDocument *_xmlDoc, ElementPtr _sdf);
   • bool initXml(TiXmlElement *_xml, ElementPtr _sdf);
   • bool readDoc(TiXmlDocument *_xmlDoc, SDFPtr _sdf, const std::string &_source);
   • bool readDoc(TiXmlDocument *_xmlDoc, ElementPtr _sdf, const std::string &_source);
   • bool readXml(TiXmlElement *_xml, ElementPtr _sdf);
   • void copyChildren(ElementPtr _sdf, TiXmlElement *_xml);
   • std::string getBestSupportedModelVersion(TiXmlElement *_modelXML, std::string &_modelFileName);

Deprecations

1. sdf/Param.hh

   • Deprecation: const std::type_info &GetType() const
   • Replacement: template bool IsType() const

2. sdf/SDFImpl.hh

   • Deprecation: ElementPtr root
   • Replacement: ElementPtr Root() const / void Root(const ElementPtr _root)
   • Deprecation: static std::string version
   • Replacement: static std::string Version()

3. sdf/Types.hh

   • Deprecation: sdf::Vector2i
   • Replacement: gz::math::Vector2i
   • Deprecation: sdf::Vector2d
   • Replacement: gz::math::Vector2d
   • Deprecation: sdf::Vector3
   • Replacement: gz::math::Vector3d
   • Deprecation: sdf::Quaternion
   • Replacement: gz::math::Quaterniond
   • Deprecation: sdf::Pose
   • Replacement: gz::math::Pose3d

SDFormat 3.x to 4.x

Additions

1. New SDFormat specification version 1.6
   • Details about the 1.5 to 1.6 transition are explained below in this same document

Modifications

1. Boost pointers and boost::function

   • All boost pointers, boost::function in the public API have been replaced by their std:: equivalents (C++11 standard)

2. Lump:: prefix in link names

   • Changed to _fixed_joint_lump__ to avoid confusion with scoped names
   • BitBucket pull request 245

SDFormat specification 1.11 to 1.12

Additions

1. joint_state.sdf:

   • //joint_state/axis_state/position
   • //joint_state/axis_state/velocity
   • //joint_state/axis_state/acceleration
   • //joint_state/axis_state/effort
   • //joint_state/axis2_state/position
   • //joint_state/axis2_state/velocity
   • //joint_state/axis2_state/acceleration
   • //joint_state/axis2_state/effort

2. link_state.sdf:

   • //link_state/linear_velocity
   • //link_state/angular_velocity
   • //link_state/linear_acceleration
   • //link_state/angular_acceleration
   • //link_state/force
   • //link_state/torque

3. model.sdf:

   • //model/model_state
   • //model/include/model_state

4. world.sdf:

   • //world/include/model_state

Modifications

1. state.sdf, model_state.sdf, joint_state.sdf, link_state.sdf, light_state.sdf: A _state suffix has been added to state element names to match the .sdf file names and for consistency.

   • //state/light renamed to //state/light_state
   • //state/model renamed to //state/model_state
   • //state/model/joint renamed to //state/model_state/joint_state
   • //state/model/light renamed to //state/model_state/light_state
   • //state/model/link renamed to //state/model_state/link_state
   • //state/model/model renamed to //state/model_state/model_state
   • //state/model/link/collision renamed to //state/model_state/link_state/collision_state

2. state.sdf: //state/joint_state has been added to represent the state of a //world/joint and //state/insertions/joint can represent inserted //world/joint elements.

Deprecations

1. joint_state.sdf:

   • //joint_state/angle is deprecated in favor of //joint_state/axis_state/position and //joint_state/axis2_state/position.

2. link_state.sdf:

   • //link_state/velocity is deprecated in favor of //link_state/angular_velocity and //link_state/linear_velocity.
   • //link_state/acceleration is deprecated in favor of //link_state/angular_acceleration and //link_state/linear_acceleration.
   • //link_state/wrench is deprecated in favor of //link_state/torque and //link_state/force.

SDFormat specification 1.10 to 1.11

Additions

1. mimic.sdf, joint.sdf: a mimic tag can be added to //joint/axis and //joint/axis2 to specify a linear relationship between the position of two joint axes according to the following equation: follower_position = multiplier * (leader_position - reference) + offset. The joint axis containing the mimic tag is the follwer and the leader is specified using the @joint and @axis attributes.

   • //mimic/@joint: name of joint containing the leader axis.
   • //mimic/@axis: name of the leader axis. Only valid values are "axis" or "axis2".
   • //mimic/multiplier: parameter representing ratio between changes in follower axis position relative to changes in leader axis position.
   • //mimic/offset: parameter representing offset to follower position.
   • //mimic/reference: parameter representing reference for leader position before applying the multiplier.

2. inertial.sdf: A new attribute //inertial/@auto has been added to specify whether the moment of inertia of a link should be calculated automatically. In addition, the following elements have been added:

   • //inertial/density: Common mass density of all collision geometries.
   • //inertial/auto_inertia_params: Container for custom parameters passed to the moment of inertia calculator.

3. collision.sdf: A new element //collision/density has been added to specify the density of a material for automatic calculation of the moment of inertia of the parent link. This parameter overrides the value in //inertial/density of the parent link if specified. In addition, //collision/auto_inertia_params can be used to override //inertial/auto_inertia_params of the parent link.

SDFormat specification 1.9 to 1.10

Additions

1. world.sdf: A joint can be specified directly in a world.
2. world.sdf: Merge-includes are now allowed in worlds. The included models must not contain top-level links or grippers.

Modifications

1. joint.sdf: axis limits default values have changed

   • //limit/lower: -inf (formerly -1e16)
   • //limit/upper: inf (formerly 1e16)
   • //limit/velocity: inf (formerly -1)
   • //limit/effort: inf (formerly -1)

2. joint.sdf: thread_pitch is deprecated in favor of screw_thread_pitch.

3. plugin.sdf: name attribute is now optional with empty default value.

Removals

1. collision_engine.sdf: unused specification file is removed.

2. urdf.sdf: unused specification file is removed.

SDFormat specification 1.8 to 1.9

Additions

1. camera.sdf: New elements to configure segmentation and boundingbox cameras

   • //sensor/camera/segmentation_type
   • //sensor/camera/box_type
   • Pull request #592

2. forcetorque.sdf: New elements to specify the noise characteristics of the force-torque sensor

   • //sensor/force_torque/force
   • //sensor/force_torque/torque
   • Pull request #669

3. model.sdf: //model/include/@merge for merging included nested models into the containing model

   • Pull request #659

4. pose.sdf: New attributes to support specifying angles in degrees and specifying rotations in quaternions

   • //pose/@rotation_format
   • //pose/@degrees
   • Pull request #690
   • Pull request #589

5. sensor.sdf: New sensor types boundingbox_camera, segmentation_camera, and custom.

   • Pull request #592

Removals

1. joint.sdf

   • Deprecated elements //joint/axis/initial_position and //joint/axis2/initial_position have been removed
   • Pull request #622

2. spherical_coordinates: Unsupported options NED and NWU have been removed from //spherical_coordinates/world_frame_orientation

   • Pull request #685

SDFormat specification 1.7 to 1.8

Additions

1. capsule.sdf and ellipsoid.sdf new shape types included in //geometry

   • capsule.sdf: A shape consisting of a cylinder capped by hemispheres with parameters for the radius and length of cylindrical section.
   • ellipsoid.sdf: A convex shape with up to three radii defining its shape in of the form (x^2/a^2 + y^2/b^2 + z^2/c^2 = 1).
   • Pull request 389
   • Pull request 434

2. light.sdf //light/intensity element

   • description: Scale factor to set the relative power of a light.
   • type: double
   • default: 1
   • required: 0
   • pull request 484

Modifications

1. joint.sdf child and parent elements accept frame names instead of only link names

   • Issue 204

2. heightmap.sdf: sampling now defaults to 1 instead of 2.

3. Element attribute names containing delimiter "::" no longer accepted

   • Issue 420

Deprecations

1. joint.sdf initial_position element in <joint><axis> and <joint><axis2> is deprecated

Removals

1. inerial.sdf //inertial/pose/@relative_to attribute is removed
   • Pull request 480

SDFormat specification 1.6 to 1.7

Additions

1. frame.sdf //frame/@attached_to attribute

   • description: Name of the link or frame to which this frame is attached. If a frame is specified, recursively following the attached_to attributes of the specified frames must lead to the name of a link, a model, or the world frame.
   • type: string
   • default: ""
   • required: *
   • BitBucket pull request 603

2. joint.sdf //axis/xyz/@expressed_in and //axis2/xyz/@expressed_in attributes

   • description: The name of the frame in which the //axis/xyz value is expressed. When migrating from sdf 1.6, a use_parent_model_frame value of true will be mapped to a value of __model__ for the expressed_in attribute.
   • type: string
   • default: ""
   • required: 0
   • BitBucket pull request 589

3. material.sdf //material/double_sided element

   • description: Flag to indicate whether the mesh that this material is applied to will be rendered as double sided.
   • type: bool
   • default: false
   • required: 0
   • pull request 418

4. model.sdf //model/@canonical_link attribute

   • description: The name of the canonical link in this model to which the model's implicit frame is attached. This implies that a model must have at least one link (unless it is static), which is also stated in the Modifications section.
   • type: string
   • default: ""
   • required: 0
   • BitBucket pull request 601

5. world.sdf //world/frame element is now allowed.

   • BitBucket pull request 603

Modifications

1. A non-static model must have at least one link, as specified in the proposal.

   • BitBucket pull request 601
   • BitBucket pull request 626

2. Unique names for all sibling elements:

   • As described in the proposal, all named sibling elements must have unique names. Uniqueness is forced so that referencing implicit frames is not ambiguous, e.g. you cannot have a link and joint share an implicit frame name. Some existing SDFormat models may not comply with this requirement. The gz sdf --check command can be used to identify models that violate this requirement.
   • BitBucket pull request 600

3. Reserved names:

   • As described in the proposal, entities in a simulation must not use world as a name. It has a special interpretation when specified as a parent or child link of a joint. Names starting and ending with double underscores (eg. __wheel__) must be reserved for use by library implementors and the specification. For example, such names might be useful during parsing for setting sentinel or default names for elements with missing names. If explicitly stated, they can be referred to (e.g. __model__ / world for implicit model / world frames, respectively).

4. joint.sdf //joint/child may no longer be specified as world.

   • BitBucket pull request 634

5. pose.sdf //pose/@frame attribute is renamed to //pose/@relative_to.

   • BitBucket pull request 597

Removals

1. <frame> element is now only allowed in <model> and <world>. It is no longer allowed in the following elements:

   • actor
   • audio_source
   • camera
   • collision
   • frame
   • gui
   • inertial
   • joint
   • light
   • light_state
   • link
   • link_state
   • population
   • projector
   • sensor
   • visual
   • BitBucket pull request 603

2. actor.sdf static element was deprecated in BitBucket pull request 280 and is now removed.

   • BitBucket pull request 588

3. imu.sdf topic element was deprecated in BitBucket pull request 532 and is now removed.

   • BitBucket pull request 588

4. joint.sdf //axis/use_parent_model_frame and //axis2/use_parent_model_frame elements are removed in favor of the //axis/xyz/@expressed_in and //axis2/xyz/@expressed_in attributes. When migrating from sdf 1.6, a use_parent_model_frame value of true will be mapped to a value of __model__ for the expressed_in attribute.

   • BitBucket pull request 589

5. joint.sdf //physics/ode/provide_feedback was deprecated in BitBucket pull request 38 and is now removed.

   • BitBucket pull request 588

6. world.sdf //world/joint was removed as it has never been used.

   • BitBucket pull request 637

SDFormat specification 1.5 to 1.6

Additions

1. actor.sdf tension element

   • description: The tension of the trajectory spline. The default value of zero equates to a Catmull-Rom spline, which may also cause the animation to overshoot keyframes. A value of one will cause the animation to stick to the keyframes.
   • type: double
   • default: 0.0
   • min: 0.0
   • max: 1.0
   • required: 0
   • BitBucket pull request 466

2. camera.sdf depth_camera/clip sub-elements: near, far

   • description: Clipping parameters for depth camera on rgbd camera sensor.
   • BitBucket pull request 628

3. camera.sdf intrinsics sub-elements: fx, fy, cx, cy, s

   • description: Camera intrinsic parameters for setting a custom perspective projection matrix.
   • BitBucket pull request 496

4. heightmap_shape.sdf sampling element

   • description: Samples per heightmap datum. For rasterized heightmaps, this indicates the number of samples to take per pixel. Using a lower value, e.g. 1, will generally improve the performance of the heightmap but lower the heightmap quality.
   • type: unsigned int
   • default: 2
   • required: 0
   • Bitbucket pull request 293

5. link.sdf enable_wind element

   • description: If true, the link is affected by the wind
   • type: bool
   • default: false
   • required: 0
   • BitBucket pull request 240

6. link.sdf light element

   • included from light.sdf with required="*", so a link can have any number of attached lights.
   • BitBucket pull request 373

7. model.sdf enable_wind element

   • description: If set to true, all links in the model will be affected by the wind. Can be overriden by the link wind property.
   • type: bool
   • default: false
   • required: 0
   • BitBucket pull request 240

8. model_state.sdf scale element

   • description: Scale for the 3 dimensions of the model.
   • type: vector3
   • default: "1 1 1"
   • required: 0
   • BitBucket pull request 246

9. physics.sdf dart::collision_detector element

   • description: The collision detector for DART to use. Can be dart, fcl, bullet or ode.
   • type: string
   • default: fcl
   • required: 0
   • BitBucket pull request 440

10. physics.sdf dart::solver::solver_type element

    • description: The DART LCP/constraint solver to use. Either dantzig or pgs (projected Gauss-Seidel)
    • type: string
    • default: dantzig
    • required: 0
    • BitBucket pull request 369

11. physics.sdf friction_model element

    • description: Name of ODE friction model to use. Valid values include:
      • pyramid_model: (default) friction forces limited in two directions in proportion to normal force.
      • box_model: friction forces limited to constant in two directions.
      • cone_model: friction force magnitude limited in proportion to normal force. See gazebo pull request 1522 (merged in gazebo 8c05ad64967c) for the implementation of this feature.
    • type: string
    • default: "pyramid_model"
    • required: 0
    • Bitbucket pull request 294

12. physics.sdf island_threads element under ode::solver

    • description: Number of threads to use for "islands" of disconnected models.
    • type: int
    • default: 0
    • required: 0
    • BitBucket pull request 380

13. physics.sdf thread_position_correction element under ode::solver

    • description: Flag to use threading to speed up position correction computation.
    • type: bool
    • default: 0
    • required: 0
    • BitBucket pull request 380

14. sonar.sdf geometry element

    • description: The sonar collision shape. Currently supported geometries are: "cone" and "sphere".
    • type: string
    • default: "cone"
    • required: 0
    • BitBucket pull request 495

15. state.sdf allow light tags within insertions element

    • BitBucket pull request 325

16. surface.sdf category_bitmask element

    • description: Bitmask for category of collision filtering. Collision happens if ((category1 & collision2) | (category2 & collision1)) is not zero. If not specified, the category_bitmask should be interpreted as being the same as collide_bitmask.
    • type: unsigned int
    • default: 65535
    • required: 0
    • BitBucket pull request 318

17. world.sdf wind element

    • description: The wind tag specifies the type and properties of the wind.
    • required: 0
    • BitBucket pull request 240

18. world.sdf wind::linear_velocity element

    • description: Linear velocity of the wind.
    • type: vector3
    • default: "0 0 0"
    • required: 0
    • BitBucket pull request 240

Modifications

1. gravity and magnetic_field elements are moved from physics to world

   • In physics element: gravity and magnetic_field tags have been moved from Physics to World element.
   • BitBucket pull request 247
   • BitBucket gazebo pull request 2090

2. New noise for IMU

   • A new style for representing the noise properties of an imu was implemented in BitBucket pull request 199 for sdf 1.5 and the old style was declared as deprecated. The old style has been removed from sdf 1.6 with the conversion script updating to the new style.
   • BitBucket pull request 199
   • BitBucket pull request 243
   • BitBucket pull request 244