Link

This module contains dataclasses for creating a link in a URDF robot model.

Dataclass

• Origin: Represents the origin of a link in the robot model.
• Axis: Represents the axis of a link in the robot model.
• Inertia: Represents the inertia properties of a link in the robot model.
• Material: Represents the material properties of a link in the robot model.
• InertialLink: Represents the inertial properties of a link in the robot model.
• VisualLink: Represents the visual properties of a link in the robot model.
• CollisionLink: Represents the collision properties of a link in the robot model.
• Link: Represents a link in the robot model.

Enum

• Colors: Enumerates the possible colors for a link in the robot model.

Axis dataclass

Represents the axis of a link in the robot model.

Attributes:

Name	Type	Description
xyz	tuple[float, float, float]	The x, y, z coordinates of the axis.

Methods:

Name	Description
to_xml	Converts the axis to an XML element.

Examples:

>>> axis = Axis(xyz=(1.0, 0.0, 0.0))
>>> axis.to_xml()
<Element 'axis' at 0x7f8b3c0b4c70>

Source code in onshape_robotics_toolkit\models\link.py

@dataclass
class Axis:
    """
    Represents the axis of a link in the robot model.

    Attributes:
        xyz (tuple[float, float, float]): The x, y, z coordinates of the axis.

    Methods:
        to_xml: Converts the axis to an XML element.

    Examples:
        >>> axis = Axis(xyz=(1.0, 0.0, 0.0))
        >>> axis.to_xml()
        <Element 'axis' at 0x7f8b3c0b4c70>
    """

    xyz: tuple[float, float, float]

    def to_xml(self, root: Optional[ET.Element] = None) -> ET.Element:
        """
        Convert the axis to an XML element.

        Args:
            root: The root element to append the axis to.

        Returns:
            The XML element representing the axis.

        Examples:
            >>> axis = Axis(xyz=(1.0, 0.0, 0.0))
            >>> axis.to_xml()
            <Element 'axis' at 0x7f8b3c0b4c70>
        """

        axis = ET.Element("axis") if root is None else ET.SubElement(root, "axis")
        axis.set("xyz", " ".join(format_number(v) for v in self.xyz))
        return axis

    def to_mjcf(self, root: ET.Element) -> None:
        """
        Convert the axis to an MuJoCo compatible XML element.

        Args:
            root: The root element to append the axis to.

        Returns:
            The XML element representing the axis.

        Examples:
            >>> axis = Axis(xyz=(1.0, 0.0, 0.0))
            >>> axis.to_mjcf()
            <Element 'axis' at 0x7f8b3c0b4c70>
        """
        root.set("axis", " ".join(format_number(v) for v in self.xyz))

    @classmethod
    def from_xml(cls, xml: ET.Element) -> "Axis":
        """
        Create an axis from an XML element.

        Args:
            xml: The XML element to create the axis from.

        Returns:
            The axis created from the XML element.

        Examples:
            >>> xml = ET.Element('axis')
            >>> Axis.from_xml(xml)
            Axis(xyz=(0.0, 0.0, 0.0))
        """
        xyz = tuple(map(float, xml.get("xyz").split()))
        return cls(xyz)

from_xml(xml) classmethod

Create an axis from an XML element.

Parameters:

Name	Type	Description	Default
xml	Element	The XML element to create the axis from.	required

Returns:

Type	Description
Axis	The axis created from the XML element.

Examples:

>>> xml = ET.Element('axis')
>>> Axis.from_xml(xml)
Axis(xyz=(0.0, 0.0, 0.0))

Source code in onshape_robotics_toolkit\models\link.py

@classmethod
def from_xml(cls, xml: ET.Element) -> "Axis":
    """
    Create an axis from an XML element.

    Args:
        xml: The XML element to create the axis from.

    Returns:
        The axis created from the XML element.

    Examples:
        >>> xml = ET.Element('axis')
        >>> Axis.from_xml(xml)
        Axis(xyz=(0.0, 0.0, 0.0))
    """
    xyz = tuple(map(float, xml.get("xyz").split()))
    return cls(xyz)

to_mjcf(root)

Convert the axis to an MuJoCo compatible XML element.

Parameters:

Name	Type	Description	Default
root	Element	The root element to append the axis to.	required

Returns:

Type	Description
None	The XML element representing the axis.

Examples:

>>> axis = Axis(xyz=(1.0, 0.0, 0.0))
>>> axis.to_mjcf()
<Element 'axis' at 0x7f8b3c0b4c70>

Source code in onshape_robotics_toolkit\models\link.py

def to_mjcf(self, root: ET.Element) -> None:
    """
    Convert the axis to an MuJoCo compatible XML element.

    Args:
        root: The root element to append the axis to.

    Returns:
        The XML element representing the axis.

    Examples:
        >>> axis = Axis(xyz=(1.0, 0.0, 0.0))
        >>> axis.to_mjcf()
        <Element 'axis' at 0x7f8b3c0b4c70>
    """
    root.set("axis", " ".join(format_number(v) for v in self.xyz))

to_xml(root=None)

Convert the axis to an XML element.

Parameters:

Name	Type	Description	Default
root	Optional[Element]	The root element to append the axis to.	None

Returns:

Type	Description
Element	The XML element representing the axis.

Examples:

>>> axis = Axis(xyz=(1.0, 0.0, 0.0))
>>> axis.to_xml()
<Element 'axis' at 0x7f8b3c0b4c70>

Source code in onshape_robotics_toolkit\models\link.py

def to_xml(self, root: Optional[ET.Element] = None) -> ET.Element:
    """
    Convert the axis to an XML element.

    Args:
        root: The root element to append the axis to.

    Returns:
        The XML element representing the axis.

    Examples:
        >>> axis = Axis(xyz=(1.0, 0.0, 0.0))
        >>> axis.to_xml()
        <Element 'axis' at 0x7f8b3c0b4c70>
    """

    axis = ET.Element("axis") if root is None else ET.SubElement(root, "axis")
    axis.set("xyz", " ".join(format_number(v) for v in self.xyz))
    return axis

CollisionLink dataclass

Represents the collision properties of a link in the robot model.

Attributes:

Name	Type	Description
origin	Origin	The origin of the link.
geometry	BaseGeometry	The geometry of the link.

Methods:

Name	Description
to_xml	Converts the collision properties to an XML element.

Examples:

>>> collision = CollisionLink(origin=Origin(...), geometry=BoxGeometry(...))
>>> collision.to_xml()
<Element 'collision' at 0x7f8b3c0b4c70>

Source code in onshape_robotics_toolkit\models\link.py

@dataclass
class CollisionLink:
    """
    Represents the collision properties of a link in the robot model.

    Attributes:
        origin (Origin): The origin of the link.
        geometry (BaseGeometry): The geometry of the link.

    Methods:
        to_xml: Converts the collision properties to an XML element.

    Examples:
        >>> collision = CollisionLink(origin=Origin(...), geometry=BoxGeometry(...))
        >>> collision.to_xml()
        <Element 'collision' at 0x7f8b3c0b4c70>
    """

    name: str
    origin: Origin
    geometry: BaseGeometry

    friction: Optional[tuple[float, float, float]] = None

    def transform(self, transformation_matrix: np.ndarray) -> None:
        """
        Apply a transformation to the visual link's origin.

        Args:
            transformation_matrix (np.ndarray): A 4x4 transformation matrix (homogeneous).
        """
        # Apply translation and rotation to the origin position
        pos = np.array([self.origin.xyz[0], self.origin.xyz[1], self.origin.xyz[2], 1])
        new_pos = transformation_matrix @ pos
        self.origin.xyz = tuple(new_pos[:3])  # Update position

        # Extract the rotation from the transformation matrix
        rotation_matrix = transformation_matrix[:3, :3]
        current_rotation = R.from_euler("xyz", self.origin.rpy)
        new_rotation = R.from_matrix(rotation_matrix @ current_rotation.as_matrix())
        self.origin.rpy = new_rotation.as_euler("xyz").tolist()

    def to_xml(self, root: Optional[ET.Element] = None) -> ET.Element:
        """
        Convert the collision properties to an XML element.

        Args:
            root: The root element to append the collision properties to.

        Returns:
            The XML element representing the collision properties.

        Examples:
            >>> collision = CollisionLink(origin=Origin(...), geometry=BoxGeometry(...))
            >>> collision.to_xml()
            <Element 'collision' at 0x7f8b3c0b4c70>
        """
        collision = ET.Element("collision") if root is None else ET.SubElement(root, "collision")
        collision.set("name", self.name)
        self.origin.to_xml(collision)
        self.geometry.to_xml(collision)
        return collision

    def to_mjcf(self, root: ET.Element) -> None:
        """
        Convert the collision properties to an MuJoCo compatible XML element.

        Example XML:
        ```xml
              <geom name="Assembly-2-1-SUB-Part-5-1-collision"
                    pos="0.0994445 -0.000366963 0.0171076"
                    quat="-0.92388 -4.28774e-08 0.382683 0"
                    type="mesh"
                    rgba="1 0.5 0 1"
                    mesh="Assembly-2-1-SUB-Part-5-1"
                    contype="1"
                    conaffinity="0"
                    density="0"
                    group="1"/>
        ```
        Args:
            root: The root element to append the collision properties to.

        Returns:
            The XML element representing the collision properties.

        Examples:
            >>> collision = CollisionLink(origin=Origin(...), geometry=BoxGeometry(...))
            >>> collision.to_mjcf()
            <Element 'collision' at 0x7f8b3c0b4c70>
        """
        collision = root if root.tag == "geom" else ET.SubElement(root, "geom")
        collision.set("name", self.name)
        collision.set("contype", "1")
        collision.set("conaffinity", "1")
        self.origin.to_mjcf(collision)

        if self.geometry:
            self.geometry.to_mjcf(collision)

        collision.set("group", "0")

        if self.friction:
            collision.set("friction", " ".join(format_number(v) for v in self.friction))

    @classmethod
    def from_xml(cls, xml: ET.Element) -> "CollisionLink":
        """
        Create a collision link from an XML element.

        Args:
            xml: The XML element to create the collision link from.

        Returns:
            The collision link created from the XML element.

        Examples:
            >>> xml = ET.Element('collision')
            >>> CollisionLink.from_xml(xml)
            CollisionLink(name='collision', origin=None, geometry=None)
        """
        name = xml.get("name")

        origin_element = xml.find("origin")
        origin = Origin.from_xml(origin_element) if origin_element is not None else None

        geometry_element = xml.find("geometry")
        geometry = set_geometry_from_xml(geometry_element) if geometry_element is not None else None

        return cls(name=name, origin=origin, geometry=geometry)

from_xml(xml) classmethod

Create a collision link from an XML element.

Parameters:

Name	Type	Description	Default
xml	Element	The XML element to create the collision link from.	required

Returns:

Type	Description
CollisionLink	The collision link created from the XML element.

Examples:

>>> xml = ET.Element('collision')
>>> CollisionLink.from_xml(xml)
CollisionLink(name='collision', origin=None, geometry=None)

Source code in onshape_robotics_toolkit\models\link.py

@classmethod
def from_xml(cls, xml: ET.Element) -> "CollisionLink":
    """
    Create a collision link from an XML element.

    Args:
        xml: The XML element to create the collision link from.

    Returns:
        The collision link created from the XML element.

    Examples:
        >>> xml = ET.Element('collision')
        >>> CollisionLink.from_xml(xml)
        CollisionLink(name='collision', origin=None, geometry=None)
    """
    name = xml.get("name")

    origin_element = xml.find("origin")
    origin = Origin.from_xml(origin_element) if origin_element is not None else None

    geometry_element = xml.find("geometry")
    geometry = set_geometry_from_xml(geometry_element) if geometry_element is not None else None

    return cls(name=name, origin=origin, geometry=geometry)

to_mjcf(root)

Convert the collision properties to an MuJoCo compatible XML element.

Example XML:

      <geom name="Assembly-2-1-SUB-Part-5-1-collision"
            pos="0.0994445 -0.000366963 0.0171076"
            quat="-0.92388 -4.28774e-08 0.382683 0"
            type="mesh"
            rgba="1 0.5 0 1"
            mesh="Assembly-2-1-SUB-Part-5-1"
            contype="1"
            conaffinity="0"
            density="0"
            group="1"/>

Args: root: The root element to append the collision properties to.

Returns:

Type	Description
None	The XML element representing the collision properties.

Examples:

>>> collision = CollisionLink(origin=Origin(...), geometry=BoxGeometry(...))
>>> collision.to_mjcf()
<Element 'collision' at 0x7f8b3c0b4c70>

Source code in onshape_robotics_toolkit\models\link.py

def to_mjcf(self, root: ET.Element) -> None:
    """
    Convert the collision properties to an MuJoCo compatible XML element.

    Example XML:
    ```xml
          <geom name="Assembly-2-1-SUB-Part-5-1-collision"
                pos="0.0994445 -0.000366963 0.0171076"
                quat="-0.92388 -4.28774e-08 0.382683 0"
                type="mesh"
                rgba="1 0.5 0 1"
                mesh="Assembly-2-1-SUB-Part-5-1"
                contype="1"
                conaffinity="0"
                density="0"
                group="1"/>
    ```
    Args:
        root: The root element to append the collision properties to.

    Returns:
        The XML element representing the collision properties.

    Examples:
        >>> collision = CollisionLink(origin=Origin(...), geometry=BoxGeometry(...))
        >>> collision.to_mjcf()
        <Element 'collision' at 0x7f8b3c0b4c70>
    """
    collision = root if root.tag == "geom" else ET.SubElement(root, "geom")
    collision.set("name", self.name)
    collision.set("contype", "1")
    collision.set("conaffinity", "1")
    self.origin.to_mjcf(collision)

    if self.geometry:
        self.geometry.to_mjcf(collision)

    collision.set("group", "0")

    if self.friction:
        collision.set("friction", " ".join(format_number(v) for v in self.friction))

to_xml(root=None)

Convert the collision properties to an XML element.

Parameters:

Name	Type	Description	Default
root	Optional[Element]	The root element to append the collision properties to.	None

Returns:

Type	Description
Element	The XML element representing the collision properties.

Examples:

>>> collision = CollisionLink(origin=Origin(...), geometry=BoxGeometry(...))
>>> collision.to_xml()
<Element 'collision' at 0x7f8b3c0b4c70>

Source code in onshape_robotics_toolkit\models\link.py

def to_xml(self, root: Optional[ET.Element] = None) -> ET.Element:
    """
    Convert the collision properties to an XML element.

    Args:
        root: The root element to append the collision properties to.

    Returns:
        The XML element representing the collision properties.

    Examples:
        >>> collision = CollisionLink(origin=Origin(...), geometry=BoxGeometry(...))
        >>> collision.to_xml()
        <Element 'collision' at 0x7f8b3c0b4c70>
    """
    collision = ET.Element("collision") if root is None else ET.SubElement(root, "collision")
    collision.set("name", self.name)
    self.origin.to_xml(collision)
    self.geometry.to_xml(collision)
    return collision

transform(transformation_matrix)

Apply a transformation to the visual link's origin.

Parameters:

Name	Type	Description	Default
transformation_matrix	ndarray	A 4x4 transformation matrix (homogeneous).	required

Source code in onshape_robotics_toolkit\models\link.py

def transform(self, transformation_matrix: np.ndarray) -> None:
    """
    Apply a transformation to the visual link's origin.

    Args:
        transformation_matrix (np.ndarray): A 4x4 transformation matrix (homogeneous).
    """
    # Apply translation and rotation to the origin position
    pos = np.array([self.origin.xyz[0], self.origin.xyz[1], self.origin.xyz[2], 1])
    new_pos = transformation_matrix @ pos
    self.origin.xyz = tuple(new_pos[:3])  # Update position

    # Extract the rotation from the transformation matrix
    rotation_matrix = transformation_matrix[:3, :3]
    current_rotation = R.from_euler("xyz", self.origin.rpy)
    new_rotation = R.from_matrix(rotation_matrix @ current_rotation.as_matrix())
    self.origin.rpy = new_rotation.as_euler("xyz").tolist()

Colors

Bases: tuple[float, float, float], Enum

Enumerates the possible colors in RGBA format for a link in the robot model.

Attributes:

Name	Type	Description
RED	tuple[float, float, float]	Color red.
GREEN	tuple[float, float, float]	Color green.
BLUE	tuple[float, float, float]	Color blue.
YELLOW	tuple[float, float, float]	Color yellow.
CYAN	tuple[float, float, float]	Color cyan.
MAGENTA	tuple[float, float, float]	Color magenta.
WHITE	tuple[float, float, float]	Color white.
BLACK	tuple[float, float, float]	Color black.
ORANGE	tuple[float, float, float]	Color orange.
PINK	tuple[float, float, float]	Color pink.

Examples:

>>> Colors.RED
<Colors.RED: (1.0, 0.0, 0.0)>

Source code in onshape_robotics_toolkit\models\link.py

class Colors(tuple[float, float, float], Enum):
    """
    Enumerates the possible colors in RGBA format for a link in the robot model.

    Attributes:
        RED (tuple[float, float, float]): Color red.
        GREEN (tuple[float, float, float]): Color green.
        BLUE (tuple[float, float, float]): Color blue.
        YELLOW (tuple[float, float, float]): Color yellow.
        CYAN (tuple[float, float, float]): Color cyan.
        MAGENTA (tuple[float, float, float]): Color magenta.
        WHITE (tuple[float, float, float]): Color white.
        BLACK (tuple[float, float, float]): Color black.
        ORANGE (tuple[float, float, float]): Color orange.
        PINK (tuple[float, float, float]): Color pink.

    Examples:
        >>> Colors.RED
        <Colors.RED: (1.0, 0.0, 0.0)>
    """

    RED = (1.0, 0.0, 0.0, 1.0)
    GREEN = (0.0, 1.0, 0.0, 1.0)
    BLUE = (0.0, 0.0, 1.0, 1.0)
    YELLOW = (1.0, 1.0, 0.0, 1.0)
    CYAN = (0.0, 1.0, 1.0, 1.0)
    MAGENTA = (1.0, 0.0, 1.0, 1.0)
    WHITE = (1.0, 1.0, 1.0, 1.0)
    BLACK = (0.0, 0.0, 0.0, 1.0)
    ORANGE = (1.0, 0.5, 0.0, 1.0)
    PINK = (1.0, 0.0, 0.5, 1.0)

Inertia dataclass

Represents the inertia tensor of a link in the robot model.

Attributes:

Name	Type	Description
ixx	float	The inertia tensor element Ixx.
iyy	float	The inertia tensor element Iyy.
izz	float	The inertia tensor element Izz.
ixy	float	The inertia tensor element Ixy.
ixz	float	The inertia tensor element Ixz.
iyz	float	The inertia tensor element Iyz.

Methods:

Name	Description
to_xml	Converts the inertia tensor to an XML element.

Examples:

>>> inertia = Inertia(ixx=1.0, iyy=2.0, izz=3.0, ixy=0.0, ixz=0.0, iyz=0.0)
>>> inertia.to_xml()
<Element 'inertia' at 0x7f8b3c0b4c70>

Source code in onshape_robotics_toolkit\models\link.py

@dataclass
class Inertia:
    """
    Represents the inertia tensor of a link in the robot model.

    Attributes:
        ixx (float): The inertia tensor element Ixx.
        iyy (float): The inertia tensor element Iyy.
        izz (float): The inertia tensor element Izz.
        ixy (float): The inertia tensor element Ixy.
        ixz (float): The inertia tensor element Ixz.
        iyz (float): The inertia tensor element Iyz.

    Methods:
        to_xml: Converts the inertia tensor to an XML element.

    Examples:
        >>> inertia = Inertia(ixx=1.0, iyy=2.0, izz=3.0, ixy=0.0, ixz=0.0, iyz=0.0)
        >>> inertia.to_xml()
        <Element 'inertia' at 0x7f8b3c0b4c70>
    """

    ixx: float
    iyy: float
    izz: float
    ixy: float
    ixz: float
    iyz: float

    def to_xml(self, root: Optional[ET.Element] = None) -> ET.Element:
        """
        Convert the inertia tensor to an XML element.

        Args:
            root: The root element to append the inertia tensor to.

        Returns:
            The XML element representing the inertia tensor.

        Examples:
            >>> inertia = Inertia(ixx=1.0, iyy=2.0, izz=3.0, ixy=0.0, ixz=0.0, iyz=0.0)
            >>> inertia.to_xml()
            <Element 'inertia' at 0x7f8b3c0b4c70>
        """

        inertia = ET.Element("inertia") if root is None else ET.SubElement(root, "inertia")
        inertia.set("ixx", format_number(self.ixx))
        inertia.set("iyy", format_number(self.iyy))
        inertia.set("izz", format_number(self.izz))
        inertia.set("ixy", format_number(self.ixy))
        inertia.set("ixz", format_number(self.ixz))
        inertia.set("iyz", format_number(self.iyz))
        return inertia

    def to_mjcf(self, root: ET.Element) -> None:
        """
        Convert the inertia tensor to an MuJoCo compatible XML element.

        Args:
            root: The root element to append the inertia tensor to.

        Returns:
            The XML element representing the inertia tensor.

        Examples:
            >>> inertia = Inertia(ixx=1.0, iyy=2.0, izz=3.0, ixy=0.0, ixz=0.0, iyz=0.0)
            >>> inertia.to_mjcf()
            <Element 'inertia' at 0x7f8b3c0b4c70>
        """
        inertial = root if root.tag == "inertial" else ET.SubElement(root, "inertial")
        inertial.set("diaginertia", " ".join(format_number(v) for v in [self.ixx, self.iyy, self.izz]))

    @classmethod
    def from_xml(cls, xml: ET.Element) -> "Inertia":
        """
        Create an inertia tensor from an XML element.

        Args:
            xml: The XML element to create the inertia tensor from.

        Returns:
            The inertia tensor created from the XML element.

        Examples:
            >>> xml = ET.Element('inertia')
            >>> Inertia.from_xml(xml)
            Inertia(ixx=0.0, iyy=0.0, izz=0.0, ixy=0.0, ixz=0.0, iyz=0.0)
        """
        ixx = float(xml.get("ixx"))
        iyy = float(xml.get("iyy"))
        izz = float(xml.get("izz"))
        ixy = float(xml.get("ixy"))
        ixz = float(xml.get("ixz"))
        iyz = float(xml.get("iyz"))
        return cls(ixx, iyy, izz, ixy, ixz, iyz)

    @classmethod
    def zero_inertia(cls) -> "Inertia":
        """
        Create an inertia tensor with zero values.

        Returns:
            The inertia tensor with zero values.

        Examples:
            >>> Inertia.zero_inertia()
            Inertia(ixx=0.0, iyy=0.0, izz=0.0, ixy=0.0, ixz=0.0, iyz=0.0)
        """
        return cls(0.0, 0.0, 0.0, 0.0, 0.0, 0.0)

from_xml(xml) classmethod

Create an inertia tensor from an XML element.

Parameters:

Name	Type	Description	Default
xml	Element	The XML element to create the inertia tensor from.	required

Returns:

Type	Description
Inertia	The inertia tensor created from the XML element.

Examples:

>>> xml = ET.Element('inertia')
>>> Inertia.from_xml(xml)
Inertia(ixx=0.0, iyy=0.0, izz=0.0, ixy=0.0, ixz=0.0, iyz=0.0)

Source code in onshape_robotics_toolkit\models\link.py

@classmethod
def from_xml(cls, xml: ET.Element) -> "Inertia":
    """
    Create an inertia tensor from an XML element.

    Args:
        xml: The XML element to create the inertia tensor from.

    Returns:
        The inertia tensor created from the XML element.

    Examples:
        >>> xml = ET.Element('inertia')
        >>> Inertia.from_xml(xml)
        Inertia(ixx=0.0, iyy=0.0, izz=0.0, ixy=0.0, ixz=0.0, iyz=0.0)
    """
    ixx = float(xml.get("ixx"))
    iyy = float(xml.get("iyy"))
    izz = float(xml.get("izz"))
    ixy = float(xml.get("ixy"))
    ixz = float(xml.get("ixz"))
    iyz = float(xml.get("iyz"))
    return cls(ixx, iyy, izz, ixy, ixz, iyz)

to_mjcf(root)

Convert the inertia tensor to an MuJoCo compatible XML element.

Parameters:

Name	Type	Description	Default
root	Element	The root element to append the inertia tensor to.	required

Returns:

Type	Description
None	The XML element representing the inertia tensor.

Examples:

>>> inertia = Inertia(ixx=1.0, iyy=2.0, izz=3.0, ixy=0.0, ixz=0.0, iyz=0.0)
>>> inertia.to_mjcf()
<Element 'inertia' at 0x7f8b3c0b4c70>

Source code in onshape_robotics_toolkit\models\link.py

def to_mjcf(self, root: ET.Element) -> None:
    """
    Convert the inertia tensor to an MuJoCo compatible XML element.

    Args:
        root: The root element to append the inertia tensor to.

    Returns:
        The XML element representing the inertia tensor.

    Examples:
        >>> inertia = Inertia(ixx=1.0, iyy=2.0, izz=3.0, ixy=0.0, ixz=0.0, iyz=0.0)
        >>> inertia.to_mjcf()
        <Element 'inertia' at 0x7f8b3c0b4c70>
    """
    inertial = root if root.tag == "inertial" else ET.SubElement(root, "inertial")
    inertial.set("diaginertia", " ".join(format_number(v) for v in [self.ixx, self.iyy, self.izz]))

to_xml(root=None)

Convert the inertia tensor to an XML element.

Parameters:

Name	Type	Description	Default
root	Optional[Element]	The root element to append the inertia tensor to.	None

Returns:

Type	Description
Element	The XML element representing the inertia tensor.

Examples:

>>> inertia = Inertia(ixx=1.0, iyy=2.0, izz=3.0, ixy=0.0, ixz=0.0, iyz=0.0)
>>> inertia.to_xml()
<Element 'inertia' at 0x7f8b3c0b4c70>

Source code in onshape_robotics_toolkit\models\link.py

def to_xml(self, root: Optional[ET.Element] = None) -> ET.Element:
    """
    Convert the inertia tensor to an XML element.

    Args:
        root: The root element to append the inertia tensor to.

    Returns:
        The XML element representing the inertia tensor.

    Examples:
        >>> inertia = Inertia(ixx=1.0, iyy=2.0, izz=3.0, ixy=0.0, ixz=0.0, iyz=0.0)
        >>> inertia.to_xml()
        <Element 'inertia' at 0x7f8b3c0b4c70>
    """

    inertia = ET.Element("inertia") if root is None else ET.SubElement(root, "inertia")
    inertia.set("ixx", format_number(self.ixx))
    inertia.set("iyy", format_number(self.iyy))
    inertia.set("izz", format_number(self.izz))
    inertia.set("ixy", format_number(self.ixy))
    inertia.set("ixz", format_number(self.ixz))
    inertia.set("iyz", format_number(self.iyz))
    return inertia

zero_inertia() classmethod

Create an inertia tensor with zero values.

Returns:

Type	Description
Inertia	The inertia tensor with zero values.

Examples:

>>> Inertia.zero_inertia()
Inertia(ixx=0.0, iyy=0.0, izz=0.0, ixy=0.0, ixz=0.0, iyz=0.0)

Source code in onshape_robotics_toolkit\models\link.py

@classmethod
def zero_inertia(cls) -> "Inertia":
    """
    Create an inertia tensor with zero values.

    Returns:
        The inertia tensor with zero values.

    Examples:
        >>> Inertia.zero_inertia()
        Inertia(ixx=0.0, iyy=0.0, izz=0.0, ixy=0.0, ixz=0.0, iyz=0.0)
    """
    return cls(0.0, 0.0, 0.0, 0.0, 0.0, 0.0)

InertialLink dataclass

Represents the inertial properties of a link in the robot model.

Attributes:

Name	Type	Description
mass	float	The mass of the link.
inertia	Inertia	The inertia properties of the link.
origin	Origin	The origin of the link.

Methods:

Name	Description
to_xml	Converts the inertial properties to an XML element.

Examples:

>>> inertial = InertialLink(mass=1.0, inertia=Inertia(...), origin=Origin(...))
>>> inertial.to_xml()
<Element 'inertial' at 0x7f8b3c0b4c70>

Source code in onshape_robotics_toolkit\models\link.py

@dataclass
class InertialLink:
    """
    Represents the inertial properties of a link in the robot model.

    Attributes:
        mass (float): The mass of the link.
        inertia (Inertia): The inertia properties of the link.
        origin (Origin): The origin of the link.

    Methods:
        to_xml: Converts the inertial properties to an XML element.

    Examples:
        >>> inertial = InertialLink(mass=1.0, inertia=Inertia(...), origin=Origin(...))
        >>> inertial.to_xml()
        <Element 'inertial' at 0x7f8b3c0b4c70>
    """

    mass: float
    inertia: Inertia
    origin: Origin

    def to_xml(self, root: Optional[ET.Element] = None) -> ET.Element:
        """
        Convert the inertial properties to an XML element.

        Args:
            root: The root element to append the inertial properties to.

        Returns:
            The XML element representing the inertial properties.

        Examples:
            >>> inertial = InertialLink(mass=1.0, inertia=Inertia(...), origin=Origin(...))
            >>> inertial.to_xml()
            <Element 'inertial' at 0x7f8b3c0b4c70>
        """
        inertial = ET.Element("inertial") if root is None else ET.SubElement(root, "inertial")
        ET.SubElement(inertial, "mass", value=format_number(self.mass))
        self.inertia.to_xml(inertial)
        self.origin.to_xml(inertial)
        return inertial

    def to_mjcf(self, root: ET.Element) -> None:
        """
        Convert the inertial properties to an MuJoCo compatible XML element.

        Example XML:
        ```xml
        <inertial pos="0 0 -0.0075" euler="0.5 0.5 -0.5" mass="0.624"
                  diaginertia="0.073541512 0.07356916 0.073543931" />
        ```
        Args:
            root: The root element to append the inertial properties to.
        """
        inertial = root if root.tag == "inertial" else ET.SubElement(root, "inertial")
        inertial.set("mass", format_number(self.mass))
        self.origin.to_mjcf(inertial)
        self.inertia.to_mjcf(inertial)

    @classmethod
    def from_xml(cls, xml: ET.Element) -> "InertialLink":
        """
        Create inertial properties from an XML element.

        Args:
            xml: The XML element to create the inertial properties from.

        Returns:
            The inertial properties created from the XML element.

        Examples:
            >>> xml = ET.Element('inertial')
            >>> InertialLink.from_xml(xml)
            InertialLink(mass=0.0, inertia=None, origin=None)
        """
        mass = float(xml.find("mass").get("value"))

        inertia_element = xml.find("inertia")
        inertia = Inertia.from_xml(inertia_element) if inertia_element is not None else None

        origin_element = xml.find("origin")
        origin = Origin.from_xml(origin_element) if origin_element is not None else None

        return cls(mass=mass, inertia=inertia, origin=origin)

from_xml(xml) classmethod

Create inertial properties from an XML element.

Parameters:

Name	Type	Description	Default
xml	Element	The XML element to create the inertial properties from.	required

Returns:

Type	Description
InertialLink	The inertial properties created from the XML element.

Examples:

>>> xml = ET.Element('inertial')
>>> InertialLink.from_xml(xml)
InertialLink(mass=0.0, inertia=None, origin=None)

Source code in onshape_robotics_toolkit\models\link.py

@classmethod
def from_xml(cls, xml: ET.Element) -> "InertialLink":
    """
    Create inertial properties from an XML element.

    Args:
        xml: The XML element to create the inertial properties from.

    Returns:
        The inertial properties created from the XML element.

    Examples:
        >>> xml = ET.Element('inertial')
        >>> InertialLink.from_xml(xml)
        InertialLink(mass=0.0, inertia=None, origin=None)
    """
    mass = float(xml.find("mass").get("value"))

    inertia_element = xml.find("inertia")
    inertia = Inertia.from_xml(inertia_element) if inertia_element is not None else None

    origin_element = xml.find("origin")
    origin = Origin.from_xml(origin_element) if origin_element is not None else None

    return cls(mass=mass, inertia=inertia, origin=origin)

to_mjcf(root)

Convert the inertial properties to an MuJoCo compatible XML element.

Example XML:

<inertial pos="0 0 -0.0075" euler="0.5 0.5 -0.5" mass="0.624"
          diaginertia="0.073541512 0.07356916 0.073543931" />

Args: root: The root element to append the inertial properties to.

Source code in onshape_robotics_toolkit\models\link.py

def to_mjcf(self, root: ET.Element) -> None:
    """
    Convert the inertial properties to an MuJoCo compatible XML element.

    Example XML:
    ```xml
    <inertial pos="0 0 -0.0075" euler="0.5 0.5 -0.5" mass="0.624"
              diaginertia="0.073541512 0.07356916 0.073543931" />
    ```
    Args:
        root: The root element to append the inertial properties to.
    """
    inertial = root if root.tag == "inertial" else ET.SubElement(root, "inertial")
    inertial.set("mass", format_number(self.mass))
    self.origin.to_mjcf(inertial)
    self.inertia.to_mjcf(inertial)

to_xml(root=None)

Convert the inertial properties to an XML element.

Parameters:

Name	Type	Description	Default
root	Optional[Element]	The root element to append the inertial properties to.	None

Returns:

Type	Description
Element	The XML element representing the inertial properties.

Examples:

>>> inertial = InertialLink(mass=1.0, inertia=Inertia(...), origin=Origin(...))
>>> inertial.to_xml()
<Element 'inertial' at 0x7f8b3c0b4c70>

Source code in onshape_robotics_toolkit\models\link.py

def to_xml(self, root: Optional[ET.Element] = None) -> ET.Element:
    """
    Convert the inertial properties to an XML element.

    Args:
        root: The root element to append the inertial properties to.

    Returns:
        The XML element representing the inertial properties.

    Examples:
        >>> inertial = InertialLink(mass=1.0, inertia=Inertia(...), origin=Origin(...))
        >>> inertial.to_xml()
        <Element 'inertial' at 0x7f8b3c0b4c70>
    """
    inertial = ET.Element("inertial") if root is None else ET.SubElement(root, "inertial")
    ET.SubElement(inertial, "mass", value=format_number(self.mass))
    self.inertia.to_xml(inertial)
    self.origin.to_xml(inertial)
    return inertial

Link dataclass

Represents a link in the robot model.

Attributes:

Name	Type	Description
name	str	The name of the link.
visual	VisualLink	The visual properties of the link.
collision	CollisionLink	The collision properties of the link.
inertial	InertialLink	The inertial properties of the link.

Methods:

Name	Description
to_xml	Converts the link to an XML element.

Class Methods

from_xml: Creates a link from an XML element.

Examples:

>>> link = Link(name="link", visual=VisualLink(...), collision=CollisionLink(...), inertial=InertialLink(...))
>>> link.to_xml()
<Element 'link' at 0x7f8b3c0b4c70>

>>> part = Part(...)
>>> Link.from_part(part)
Link(name='partId', visual=None, collision=None, inertial=None)

Source code in onshape_robotics_toolkit\models\link.py

@dataclass
class Link:
    """
    Represents a link in the robot model.

    Attributes:
        name (str): The name of the link.
        visual (VisualLink): The visual properties of the link.
        collision (CollisionLink): The collision properties of the link.
        inertial (InertialLink): The inertial properties of the link.

    Methods:
        to_xml: Converts the link to an XML element.

    Class Methods:
        from_xml: Creates a link from an XML element.

    Examples:
        >>> link = Link(name="link", visual=VisualLink(...), collision=CollisionLink(...), inertial=InertialLink(...))
        >>> link.to_xml()
        <Element 'link' at 0x7f8b3c0b4c70>

        >>> part = Part(...)
        >>> Link.from_part(part)
        Link(name='partId', visual=None, collision=None, inertial=None)
    """

    name: str
    visual: VisualLink | None = None
    collision: CollisionLink | None = None
    inertial: InertialLink | None = None

    def to_xml(self, root: Optional[ET.Element] = None) -> ET.Element:
        """
        Convert the link to an XML element.

        Args:
            root: The root element to append the link to.

        Returns:
            The XML element representing the link.

        Examples:
            >>> link = Link(
            ...     name="link",
            ...     visual=VisualLink(...),
            ...     collision=CollisionLink(...),
            ...     inertial=InertialLink(...),
            ... )
            >>> link.to_xml()
            <Element 'link' at 0x7f8b3c0b4c70>
        """
        link = ET.Element("link") if root is None else ET.SubElement(root, "link")
        link.set("name", self.name)
        if self.visual is not None:
            self.visual.to_xml(link)
        if self.collision is not None:
            self.collision.to_xml(link)
        if self.inertial is not None:
            self.inertial.to_xml(link)
        return link

    def to_mjcf(self, root: Optional[ET.Element] = None) -> ET.Element:
        """
        Convert the link to an MuJoCo compatible XML element.

        Args:
            root: The root element to append the link to.

        Returns:
            The XML element representing the link.

        Examples:
            >>> link = Link(
            ...     name="link",
            ...     visual=VisualLink(...),
            ...     collision=CollisionLink(...),
            ...     inertial=InertialLink(...),
            ... )
            >>> link.to_mjcf()
            <Element 'link' at 0x7f8b3c0b4c70>
        """
        link = ET.Element("body") if root is None else ET.SubElement(root, "body")
        link.set("name", self.name)

        if self.visual:
            link.set("pos", " ".join(map(str, self.visual.origin.xyz)))
            link.set("euler", " ".join(map(str, self.visual.origin.rpy)))

        if self.collision:
            self.collision.to_mjcf(link)

        if self.visual:
            self.visual.to_mjcf(link)

        if self.inertial:
            self.inertial.to_mjcf(link)

        return link

    @classmethod
    def from_xml(cls, xml: ET.Element) -> "Link":
        """
        Create a link from an XML element.

        Args:
            xml: The XML element to create the link from.

        Returns:
            The link created from the XML element.

        Examples:
            >>> xml = ET.Element('link')
            >>> Link.from_xml(xml)
            Link(name='link', visual=None, collision=None, inertial=None)
        """
        name = xml.get("name")

        visual_element = xml.find("visual")
        visual = VisualLink.from_xml(visual_element) if visual_element is not None else None

        collision_element = xml.find("collision")
        collision = CollisionLink.from_xml(collision_element) if collision_element is not None else None

        inertial_element = xml.find("inertial")
        inertial = InertialLink.from_xml(inertial_element) if inertial_element is not None else None

        return cls(name=name, visual=visual, collision=collision, inertial=inertial)

from_xml(xml) classmethod

Create a link from an XML element.

Parameters:

Name	Type	Description	Default
xml	Element	The XML element to create the link from.	required

Returns:

Type	Description
Link	The link created from the XML element.

Examples:

>>> xml = ET.Element('link')
>>> Link.from_xml(xml)
Link(name='link', visual=None, collision=None, inertial=None)

Source code in onshape_robotics_toolkit\models\link.py

@classmethod
def from_xml(cls, xml: ET.Element) -> "Link":
    """
    Create a link from an XML element.

    Args:
        xml: The XML element to create the link from.

    Returns:
        The link created from the XML element.

    Examples:
        >>> xml = ET.Element('link')
        >>> Link.from_xml(xml)
        Link(name='link', visual=None, collision=None, inertial=None)
    """
    name = xml.get("name")

    visual_element = xml.find("visual")
    visual = VisualLink.from_xml(visual_element) if visual_element is not None else None

    collision_element = xml.find("collision")
    collision = CollisionLink.from_xml(collision_element) if collision_element is not None else None

    inertial_element = xml.find("inertial")
    inertial = InertialLink.from_xml(inertial_element) if inertial_element is not None else None

    return cls(name=name, visual=visual, collision=collision, inertial=inertial)

to_mjcf(root=None)

Convert the link to an MuJoCo compatible XML element.

Parameters:

Name	Type	Description	Default
root	Optional[Element]	The root element to append the link to.	None

Returns:

Type	Description
Element	The XML element representing the link.

Examples:

>>> link = Link(
...     name="link",
...     visual=VisualLink(...),
...     collision=CollisionLink(...),
...     inertial=InertialLink(...),
... )
>>> link.to_mjcf()
<Element 'link' at 0x7f8b3c0b4c70>

Source code in onshape_robotics_toolkit\models\link.py

def to_mjcf(self, root: Optional[ET.Element] = None) -> ET.Element:
    """
    Convert the link to an MuJoCo compatible XML element.

    Args:
        root: The root element to append the link to.

    Returns:
        The XML element representing the link.

    Examples:
        >>> link = Link(
        ...     name="link",
        ...     visual=VisualLink(...),
        ...     collision=CollisionLink(...),
        ...     inertial=InertialLink(...),
        ... )
        >>> link.to_mjcf()
        <Element 'link' at 0x7f8b3c0b4c70>
    """
    link = ET.Element("body") if root is None else ET.SubElement(root, "body")
    link.set("name", self.name)

    if self.visual:
        link.set("pos", " ".join(map(str, self.visual.origin.xyz)))
        link.set("euler", " ".join(map(str, self.visual.origin.rpy)))

    if self.collision:
        self.collision.to_mjcf(link)

    if self.visual:
        self.visual.to_mjcf(link)

    if self.inertial:
        self.inertial.to_mjcf(link)

    return link

to_xml(root=None)

Convert the link to an XML element.

Parameters:

Name	Type	Description	Default
root	Optional[Element]	The root element to append the link to.	None

Returns:

Type	Description
Element	The XML element representing the link.

Examples:

>>> link = Link(
...     name="link",
...     visual=VisualLink(...),
...     collision=CollisionLink(...),
...     inertial=InertialLink(...),
... )
>>> link.to_xml()
<Element 'link' at 0x7f8b3c0b4c70>

Source code in onshape_robotics_toolkit\models\link.py

def to_xml(self, root: Optional[ET.Element] = None) -> ET.Element:
    """
    Convert the link to an XML element.

    Args:
        root: The root element to append the link to.

    Returns:
        The XML element representing the link.

    Examples:
        >>> link = Link(
        ...     name="link",
        ...     visual=VisualLink(...),
        ...     collision=CollisionLink(...),
        ...     inertial=InertialLink(...),
        ... )
        >>> link.to_xml()
        <Element 'link' at 0x7f8b3c0b4c70>
    """
    link = ET.Element("link") if root is None else ET.SubElement(root, "link")
    link.set("name", self.name)
    if self.visual is not None:
        self.visual.to_xml(link)
    if self.collision is not None:
        self.collision.to_xml(link)
    if self.inertial is not None:
        self.inertial.to_xml(link)
    return link

Material dataclass

Represents the material properties of a link in the robot model.

Attributes:

Name	Type	Description
name	str	The name of the material.
color	tuple[float, float, float, float]	The color of the material in RGBA format.

Methods:

Name	Description
to_xml	Converts the material properties to an XML element.

Class Methods

from_color: Creates a material from a color.

Examples:

>>> material = Material(name="material", color=(1.0, 0.0, 0.0, 1.0))
>>> material.to_xml()
<Element 'material' at 0x7f8b3c0b4c70>

>>> Material.from_color(name="material", color=Colors.RED)
Material(name='material', color=(1.0, 0.0, 0.0, 1.0))

Source code in onshape_robotics_toolkit\models\link.py

@dataclass
class Material:
    """
    Represents the material properties of a link in the robot model.

    Attributes:
        name (str): The name of the material.
        color (tuple[float, float, float, float]): The color of the material in RGBA format.

    Methods:
        to_xml: Converts the material properties to an XML element.

    Class Methods:
        from_color: Creates a material from a color.

    Examples:
        >>> material = Material(name="material", color=(1.0, 0.0, 0.0, 1.0))
        >>> material.to_xml()
        <Element 'material' at 0x7f8b3c0b4c70>

        >>> Material.from_color(name="material", color=Colors.RED)
        Material(name='material', color=(1.0, 0.0, 0.0, 1.0))
    """

    name: str
    color: tuple[float, float, float, float]

    def to_xml(self, root: Optional[ET.Element] = None) -> ET.Element:
        """
        Convert the material properties to an XML element.

        Args:
            root: The root element to append the material properties to.

        Returns:
            The XML element representing the material properties.

        Examples:
            >>> material = Material(name="material", color=(1.0, 0.0, 0.0, 1.0))
            >>> material.to_xml()
            <Element 'material' at 0x7f8b3c0b4c70>
        """

        material = ET.Element("material") if root is None else ET.SubElement(root, "material")
        material.set("name", self.name)
        ET.SubElement(material, "color", rgba=" ".join(format_number(v) for v in self.color))
        return material

    def to_mjcf(self, root: ET.Element) -> None:
        """
        Convert the material properties to an MuJoCo compatible XML element.

        Args:
            root: The root element to append the material properties to.

        Returns:
            The XML element representing the material properties.

        Examples:
            >>> material = Material(name="material", color=(1.0, 0.0, 0.0, 1.0))
            >>> material.to_mjcf()
            <Element 'material' at 0x7f8b3c0b4c70>
        """
        geom = root if root is not None and root.tag == "geom" else ET.SubElement(root, "geom")
        geom.set("rgba", " ".join(format_number(v) for v in self.color))

    @classmethod
    def from_xml(cls, xml: ET.Element) -> "Material":
        """
        Create a material from an XML element.

        Args:
            xml: The XML element to create the material from.

        Returns:
            The material created from the XML element.

        Examples:
            >>> xml = ET.Element('material')
            >>> Material.from_xml(xml)
            Material(name='material', color=(1.0, 0.0, 0.0, 1.0))
        """

        name = xml.get("name")
        color = tuple(map(float, xml.find("color").get("rgba").split()))
        return cls(name, color)

    @classmethod
    def from_color(cls, name: str, color: Colors) -> "Material":
        """
        Create a material from a color.

        Args:
            name: The name of the material.
            color: The color of the material.

        Returns:
            The material created from the color.

        Examples:
            >>> Material.from_color(name="material", color=Colors.RED)
            Material(name='material', color=(1.0, 0.0, 0.0, 1.0))
        """
        return cls(name, color)

from_color(name, color) classmethod

Create a material from a color.

Parameters:

Name	Type	Description	Default
name	str	The name of the material.	required
color	Colors	The color of the material.	required

Returns:

Type	Description
Material	The material created from the color.

Examples:

>>> Material.from_color(name="material", color=Colors.RED)
Material(name='material', color=(1.0, 0.0, 0.0, 1.0))

Source code in onshape_robotics_toolkit\models\link.py

@classmethod
def from_color(cls, name: str, color: Colors) -> "Material":
    """
    Create a material from a color.

    Args:
        name: The name of the material.
        color: The color of the material.

    Returns:
        The material created from the color.

    Examples:
        >>> Material.from_color(name="material", color=Colors.RED)
        Material(name='material', color=(1.0, 0.0, 0.0, 1.0))
    """
    return cls(name, color)

from_xml(xml) classmethod

Create a material from an XML element.

Parameters:

Name	Type	Description	Default
xml	Element	The XML element to create the material from.	required

Returns:

Type	Description
Material	The material created from the XML element.

Examples:

>>> xml = ET.Element('material')
>>> Material.from_xml(xml)
Material(name='material', color=(1.0, 0.0, 0.0, 1.0))

Source code in onshape_robotics_toolkit\models\link.py

@classmethod
def from_xml(cls, xml: ET.Element) -> "Material":
    """
    Create a material from an XML element.

    Args:
        xml: The XML element to create the material from.

    Returns:
        The material created from the XML element.

    Examples:
        >>> xml = ET.Element('material')
        >>> Material.from_xml(xml)
        Material(name='material', color=(1.0, 0.0, 0.0, 1.0))
    """

    name = xml.get("name")
    color = tuple(map(float, xml.find("color").get("rgba").split()))
    return cls(name, color)

to_mjcf(root)

Convert the material properties to an MuJoCo compatible XML element.

Parameters:

Name	Type	Description	Default
root	Element	The root element to append the material properties to.	required

Returns:

Type	Description
None	The XML element representing the material properties.

Examples:

>>> material = Material(name="material", color=(1.0, 0.0, 0.0, 1.0))
>>> material.to_mjcf()
<Element 'material' at 0x7f8b3c0b4c70>

Source code in onshape_robotics_toolkit\models\link.py

def to_mjcf(self, root: ET.Element) -> None:
    """
    Convert the material properties to an MuJoCo compatible XML element.

    Args:
        root: The root element to append the material properties to.

    Returns:
        The XML element representing the material properties.

    Examples:
        >>> material = Material(name="material", color=(1.0, 0.0, 0.0, 1.0))
        >>> material.to_mjcf()
        <Element 'material' at 0x7f8b3c0b4c70>
    """
    geom = root if root is not None and root.tag == "geom" else ET.SubElement(root, "geom")
    geom.set("rgba", " ".join(format_number(v) for v in self.color))

to_xml(root=None)

Convert the material properties to an XML element.

Parameters:

Name	Type	Description	Default
root	Optional[Element]	The root element to append the material properties to.	None

Returns:

Type	Description
Element	The XML element representing the material properties.

Examples:

>>> material = Material(name="material", color=(1.0, 0.0, 0.0, 1.0))
>>> material.to_xml()
<Element 'material' at 0x7f8b3c0b4c70>

Source code in onshape_robotics_toolkit\models\link.py

def to_xml(self, root: Optional[ET.Element] = None) -> ET.Element:
    """
    Convert the material properties to an XML element.

    Args:
        root: The root element to append the material properties to.

    Returns:
        The XML element representing the material properties.

    Examples:
        >>> material = Material(name="material", color=(1.0, 0.0, 0.0, 1.0))
        >>> material.to_xml()
        <Element 'material' at 0x7f8b3c0b4c70>
    """

    material = ET.Element("material") if root is None else ET.SubElement(root, "material")
    material.set("name", self.name)
    ET.SubElement(material, "color", rgba=" ".join(format_number(v) for v in self.color))
    return material

Origin dataclass

Represents the origin of a link in the robot model.

Attributes:

Name	Type	Description
xyz	tuple[float, float, float]	The x, y, z coordinates of the origin.
rpy	tuple[float, float, float]	The roll, pitch, yaw angles of the origin.

Methods:

Name	Description
to_xml	Converts the origin to an XML element.

Class Methods

from_matrix: Creates an origin from a transformation matrix. zero_origin: Creates an origin at the origin (0, 0, 0) with no rotation.

Examples:

>>> origin = Origin(xyz=(1.0, 2.0, 3.0), rpy=(0.0, 0.0, 0.0))
>>> origin.to_xml()
<Element 'origin' at 0x7f8b3c0b4c70>

>>> matrix = np.matrix([
...     [1, 0, 0, 0],
...     [0, 1, 0, 0],
...     [0, 0, 1, 0],
...     [0, 0, 0, 1],
... ])
>>> Origin.from_matrix(matrix)
Origin(xyz=(0.0, 0.0, 0.0), rpy=(0.0, 0.0, 0.0))

>>> Origin.zero_origin()
Origin(xyz=(0.0, 0.0, 0.0), rpy=(0.0, 0.0, 0.0))

Source code in onshape_robotics_toolkit\models\link.py

@dataclass
class Origin:
    """
    Represents the origin of a link in the robot model.

    Attributes:
        xyz (tuple[float, float, float]): The x, y, z coordinates of the origin.
        rpy (tuple[float, float, float]): The roll, pitch, yaw angles of the origin.

    Methods:
        to_xml: Converts the origin to an XML element.

    Class Methods:
        from_matrix: Creates an origin from a transformation matrix.
        zero_origin: Creates an origin at the origin (0, 0, 0) with no rotation.

    Examples:
        >>> origin = Origin(xyz=(1.0, 2.0, 3.0), rpy=(0.0, 0.0, 0.0))
        >>> origin.to_xml()
        <Element 'origin' at 0x7f8b3c0b4c70>

        >>> matrix = np.matrix([
        ...     [1, 0, 0, 0],
        ...     [0, 1, 0, 0],
        ...     [0, 0, 1, 0],
        ...     [0, 0, 0, 1],
        ... ])
        >>> Origin.from_matrix(matrix)
        Origin(xyz=(0.0, 0.0, 0.0), rpy=(0.0, 0.0, 0.0))

        >>> Origin.zero_origin()
        Origin(xyz=(0.0, 0.0, 0.0), rpy=(0.0, 0.0, 0.0))
    """

    xyz: tuple[float, float, float]
    rpy: tuple[float, float, float]

    def transform(self, matrix: np.matrix, inplace: bool = False) -> Union["Origin", None]:
        """
        Apply a transformation matrix to the origin.

        Args:
            matrix: The transformation matrix to apply to the origin.
            inplace: Whether to apply the transformation in place.

        Returns:
            The origin with the transformation applied.

        Examples:
            >>> origin = Origin(xyz=(1.0, 2.0, 3.0), rpy=(0.0, 0.0, 0.0))
            >>> matrix = np.eye(4)
            >>> origin.transform(matrix)
        """
        new_xyz = np.dot(matrix[:3, :3], np.array(self.xyz)) + matrix[:3, 3]
        current_rotation_matrix = Rotation.from_euler("xyz", self.rpy).as_matrix()

        new_rotation_matrix = np.dot(matrix[:3, :3], current_rotation_matrix)
        new_rpy = Rotation.from_matrix(new_rotation_matrix).as_euler("xyz")
        if inplace:
            self.xyz = tuple(new_xyz)
            self.rpy = tuple(new_rpy)
            return None

        return Origin(new_xyz, new_rpy)

    def to_xml(self, root: Optional[ET.Element] = None) -> ET.Element:
        """
        Convert the origin to an XML element.

        Args:
            root: The root element to append the origin to.

        Returns:
            The XML element representing the origin.

        Examples:
            >>> origin = Origin(xyz=(1.0, 2.0, 3.0), rpy=(0.0, 0.0, 0.0))
            >>> origin.to_xml()
            <Element 'origin' at 0x7f8b3c0b4c70>
        """

        origin = ET.Element("origin") if root is None else ET.SubElement(root, "origin")
        origin.set("xyz", " ".join(format_number(v) for v in self.xyz))
        origin.set("rpy", " ".join(format_number(v) for v in self.rpy))
        return origin

    def to_mjcf(self, root: ET.Element) -> None:
        """
        Convert the origin to an MuJoCo compatible XML element.

        Args:
            root: The root element to append the origin to.

        Returns:
            The XML element representing the origin.

        Examples:
            >>> origin = Origin(xyz=(1.0, 2.0, 3.0), rpy=(0.0, 0.0, 0.0))
            >>> origin.to_mjcf()
            <Element 'origin' at 0x7f8b3c0b4c70>
        """
        root.set("pos", " ".join(format_number(v) for v in self.xyz))
        root.set("euler", " ".join(format_number(v) for v in self.rpy))

    @classmethod
    def from_xml(cls, xml: ET.Element) -> "Origin":
        """
        Create an origin from an XML element.

        Args:
            xml: The XML element to create the origin from.

        Returns:
            The origin created from the XML element.

        Examples:
            >>> xml = ET.Element('origin')
            >>> Origin.from_xml(xml)
            Origin(xyz=(0.0, 0.0, 0.0), rpy=(0.0, 0.0, 0.0))
        """

        xyz = tuple(map(float, xml.get("xyz").split()))
        rpy = tuple(map(float, xml.get("rpy").split()))
        return cls(xyz, rpy)

    def quat(self, sequence: str = "xyz") -> str:
        """
        Convert the origin to a quaternion.

        Args:
            sequence: The sequence of the Euler angles.

        Returns:
            The quaternion representing the origin.
        """
        return Rotation.from_euler(sequence, self.rpy).as_quat()

    @classmethod
    def from_matrix(cls, matrix: np.matrix) -> "Origin":
        """
        Create an origin from a transformation matrix.

        Args:
            matrix: The transformation matrix.

        Returns:
            The origin created from the transformation matrix.

        Examples:
            >>> matrix = np.matrix([
            ...     [1, 0, 0, 0],
            ...     [0, 1, 0, 0],
            ...     [0, 0, 1, 0],
            ...     [0, 0, 0, 1],
            ... ])
            >>> Origin.from_matrix(matrix)
            Origin(xyz=(0.0, 0.0, 0.0), rpy=(0.0, 0.0, 0.0))
        """

        x = float(matrix[0, 3])
        y = float(matrix[1, 3])
        z = float(matrix[2, 3])
        roll, pitch, yaw = Rotation.from_matrix(matrix[:3, :3]).as_euler("xyz")
        return cls((x, y, z), (roll, pitch, yaw))

    @classmethod
    def zero_origin(cls) -> "Origin":
        """
        Create an origin at the origin (0, 0, 0) with no rotation.

        Returns:
            The origin at the origin (0, 0, 0) with no rotation.

        Examples:
            >>> Origin.zero_origin()
            Origin(xyz=(0.0, 0.0, 0.0), rpy=(0.0, 0.0, 0.0))
        """

        return cls((0.0, 0.0, 0.0), (0.0, 0.0, 0.0))

from_matrix(matrix) classmethod

Create an origin from a transformation matrix.

Parameters:

Name	Type	Description	Default
matrix	matrix	The transformation matrix.	required

Returns:

Type	Description
Origin	The origin created from the transformation matrix.

Examples:

>>> matrix = np.matrix([
...     [1, 0, 0, 0],
...     [0, 1, 0, 0],
...     [0, 0, 1, 0],
...     [0, 0, 0, 1],
... ])
>>> Origin.from_matrix(matrix)
Origin(xyz=(0.0, 0.0, 0.0), rpy=(0.0, 0.0, 0.0))

Source code in onshape_robotics_toolkit\models\link.py

@classmethod
def from_matrix(cls, matrix: np.matrix) -> "Origin":
    """
    Create an origin from a transformation matrix.

    Args:
        matrix: The transformation matrix.

    Returns:
        The origin created from the transformation matrix.

    Examples:
        >>> matrix = np.matrix([
        ...     [1, 0, 0, 0],
        ...     [0, 1, 0, 0],
        ...     [0, 0, 1, 0],
        ...     [0, 0, 0, 1],
        ... ])
        >>> Origin.from_matrix(matrix)
        Origin(xyz=(0.0, 0.0, 0.0), rpy=(0.0, 0.0, 0.0))
    """

    x = float(matrix[0, 3])
    y = float(matrix[1, 3])
    z = float(matrix[2, 3])
    roll, pitch, yaw = Rotation.from_matrix(matrix[:3, :3]).as_euler("xyz")
    return cls((x, y, z), (roll, pitch, yaw))

from_xml(xml) classmethod

Create an origin from an XML element.

Parameters:

Name	Type	Description	Default
xml	Element	The XML element to create the origin from.	required

Returns:

Type	Description
Origin	The origin created from the XML element.

Examples:

>>> xml = ET.Element('origin')
>>> Origin.from_xml(xml)
Origin(xyz=(0.0, 0.0, 0.0), rpy=(0.0, 0.0, 0.0))

Source code in onshape_robotics_toolkit\models\link.py

@classmethod
def from_xml(cls, xml: ET.Element) -> "Origin":
    """
    Create an origin from an XML element.

    Args:
        xml: The XML element to create the origin from.

    Returns:
        The origin created from the XML element.

    Examples:
        >>> xml = ET.Element('origin')
        >>> Origin.from_xml(xml)
        Origin(xyz=(0.0, 0.0, 0.0), rpy=(0.0, 0.0, 0.0))
    """

    xyz = tuple(map(float, xml.get("xyz").split()))
    rpy = tuple(map(float, xml.get("rpy").split()))
    return cls(xyz, rpy)

quat(sequence='xyz')

Convert the origin to a quaternion.

Parameters:

Name	Type	Description	Default
sequence	str	The sequence of the Euler angles.	'xyz'

Returns:

Type	Description
str	The quaternion representing the origin.

Source code in onshape_robotics_toolkit\models\link.py

def quat(self, sequence: str = "xyz") -> str:
    """
    Convert the origin to a quaternion.

    Args:
        sequence: The sequence of the Euler angles.

    Returns:
        The quaternion representing the origin.
    """
    return Rotation.from_euler(sequence, self.rpy).as_quat()

to_mjcf(root)

Convert the origin to an MuJoCo compatible XML element.

Parameters:

Name	Type	Description	Default
root	Element	The root element to append the origin to.	required

Returns:

Type	Description
None	The XML element representing the origin.

Examples:

>>> origin = Origin(xyz=(1.0, 2.0, 3.0), rpy=(0.0, 0.0, 0.0))
>>> origin.to_mjcf()
<Element 'origin' at 0x7f8b3c0b4c70>

Source code in onshape_robotics_toolkit\models\link.py

def to_mjcf(self, root: ET.Element) -> None:
    """
    Convert the origin to an MuJoCo compatible XML element.

    Args:
        root: The root element to append the origin to.

    Returns:
        The XML element representing the origin.

    Examples:
        >>> origin = Origin(xyz=(1.0, 2.0, 3.0), rpy=(0.0, 0.0, 0.0))
        >>> origin.to_mjcf()
        <Element 'origin' at 0x7f8b3c0b4c70>
    """
    root.set("pos", " ".join(format_number(v) for v in self.xyz))
    root.set("euler", " ".join(format_number(v) for v in self.rpy))

to_xml(root=None)

Convert the origin to an XML element.

Parameters:

Name	Type	Description	Default
root	Optional[Element]	The root element to append the origin to.	None

Returns:

Type	Description
Element	The XML element representing the origin.

Examples:

>>> origin = Origin(xyz=(1.0, 2.0, 3.0), rpy=(0.0, 0.0, 0.0))
>>> origin.to_xml()
<Element 'origin' at 0x7f8b3c0b4c70>

Source code in onshape_robotics_toolkit\models\link.py

def to_xml(self, root: Optional[ET.Element] = None) -> ET.Element:
    """
    Convert the origin to an XML element.

    Args:
        root: The root element to append the origin to.

    Returns:
        The XML element representing the origin.

    Examples:
        >>> origin = Origin(xyz=(1.0, 2.0, 3.0), rpy=(0.0, 0.0, 0.0))
        >>> origin.to_xml()
        <Element 'origin' at 0x7f8b3c0b4c70>
    """

    origin = ET.Element("origin") if root is None else ET.SubElement(root, "origin")
    origin.set("xyz", " ".join(format_number(v) for v in self.xyz))
    origin.set("rpy", " ".join(format_number(v) for v in self.rpy))
    return origin

transform(matrix, inplace=False)

Apply a transformation matrix to the origin.

Parameters:

Name	Type	Description	Default
matrix	matrix	The transformation matrix to apply to the origin.	required
inplace	bool	Whether to apply the transformation in place.	False

Returns:

Type	Description
Union[Origin, None]	The origin with the transformation applied.

Examples:

>>> origin = Origin(xyz=(1.0, 2.0, 3.0), rpy=(0.0, 0.0, 0.0))
>>> matrix = np.eye(4)
>>> origin.transform(matrix)

Source code in onshape_robotics_toolkit\models\link.py

def transform(self, matrix: np.matrix, inplace: bool = False) -> Union["Origin", None]:
    """
    Apply a transformation matrix to the origin.

    Args:
        matrix: The transformation matrix to apply to the origin.
        inplace: Whether to apply the transformation in place.

    Returns:
        The origin with the transformation applied.

    Examples:
        >>> origin = Origin(xyz=(1.0, 2.0, 3.0), rpy=(0.0, 0.0, 0.0))
        >>> matrix = np.eye(4)
        >>> origin.transform(matrix)
    """
    new_xyz = np.dot(matrix[:3, :3], np.array(self.xyz)) + matrix[:3, 3]
    current_rotation_matrix = Rotation.from_euler("xyz", self.rpy).as_matrix()

    new_rotation_matrix = np.dot(matrix[:3, :3], current_rotation_matrix)
    new_rpy = Rotation.from_matrix(new_rotation_matrix).as_euler("xyz")
    if inplace:
        self.xyz = tuple(new_xyz)
        self.rpy = tuple(new_rpy)
        return None

    return Origin(new_xyz, new_rpy)

zero_origin() classmethod

Create an origin at the origin (0, 0, 0) with no rotation.

Returns:

Type	Description
Origin	The origin at the origin (0, 0, 0) with no rotation.

Examples:

>>> Origin.zero_origin()
Origin(xyz=(0.0, 0.0, 0.0), rpy=(0.0, 0.0, 0.0))

Source code in onshape_robotics_toolkit\models\link.py

@classmethod
def zero_origin(cls) -> "Origin":
    """
    Create an origin at the origin (0, 0, 0) with no rotation.

    Returns:
        The origin at the origin (0, 0, 0) with no rotation.

    Examples:
        >>> Origin.zero_origin()
        Origin(xyz=(0.0, 0.0, 0.0), rpy=(0.0, 0.0, 0.0))
    """

    return cls((0.0, 0.0, 0.0), (0.0, 0.0, 0.0))

VisualLink dataclass

Represents the visual properties of a link in the robot model.

Attributes:

Name	Type	Description
origin	Origin	The origin of the link.
geometry	BaseGeometry	The geometry of the link.
material	Material	The material properties of the link.

Methods:

Name	Description
to_xml	Converts the visual properties to an XML element.

Examples:

>>> visual = VisualLink(origin=Origin(...), geometry=BoxGeometry(...), material=Material(...))
>>> visual.to_xml()
<Element 'visual' at 0x7f8b3c0b4c70>

Source code in onshape_robotics_toolkit\models\link.py

@dataclass
class VisualLink:
    """
    Represents the visual properties of a link in the robot model.

    Attributes:
        origin (Origin): The origin of the link.
        geometry (BaseGeometry): The geometry of the link.
        material (Material): The material properties of the link.

    Methods:
        to_xml: Converts the visual properties to an XML element.

    Examples:
        >>> visual = VisualLink(origin=Origin(...), geometry=BoxGeometry(...), material=Material(...))
        >>> visual.to_xml()
        <Element 'visual' at 0x7f8b3c0b4c70>
    """

    name: str
    origin: Origin
    geometry: BaseGeometry
    material: Material

    def transform(self, transformation_matrix: np.ndarray) -> None:
        """
        Apply a transformation to the visual link's origin.

        Args:
            transformation_matrix (np.ndarray): A 4x4 transformation matrix (homogeneous).
        """
        # Apply translation and rotation to the origin position
        pos = np.array([self.origin.xyz[0], self.origin.xyz[1], self.origin.xyz[2], 1])
        new_pos = transformation_matrix @ pos
        self.origin.xyz = tuple(new_pos[:3])  # Update position

        # Extract the rotation from the transformation matrix
        rotation_matrix = transformation_matrix[:3, :3]
        current_rotation = R.from_euler("xyz", self.origin.rpy)
        new_rotation = R.from_matrix(rotation_matrix @ current_rotation.as_matrix())
        self.origin.rpy = new_rotation.as_euler("xyz").tolist()

    def to_xml(self, root: Optional[ET.Element] = None) -> ET.Element:
        """
        Convert the visual properties to an XML element.

        Args:
            root: The root element to append the visual properties to.

        Returns:
            The XML element representing the visual properties.

        Examples:
            >>> visual = VisualLink(origin=Origin(...), geometry=BoxGeometry(...), material=Material(...))
            >>> visual.to_xml()
            <Element 'visual' at 0x7f8b3c0b4c70>
        """
        visual = ET.Element("visual") if root is None else ET.SubElement(root, "visual")
        visual.set("name", self.name)
        self.origin.to_xml(visual)
        self.geometry.to_xml(visual)
        self.material.to_xml(visual)
        return visual

    def to_mjcf(self, root: ET.Element) -> None:
        """
        Convert the visual properties to an MuJoCo compatible XML element.

        Args:
            root: The root element to append the visual properties to.

        Returns:
            The XML element representing the visual properties.

        Examples:
            >>> visual = VisualLink(origin=Origin(...), geometry=BoxGeometry(...), material=Material(...))
            >>> visual.to_mjcf()
            <Element 'visual' at 0x7f8b3c0b4c70>
        """
        visual = root if root.tag == "geom" else ET.SubElement(root, "geom")
        visual.set("name", self.name)
        # TODO: Parent body uses visual origin, these share the same?
        self.origin.to_mjcf(visual)

        if self.geometry:
            self.geometry.to_mjcf(visual)

        self.material.to_mjcf(visual)

        visual.set("conaffinity", "0")
        visual.set("condim", "1")
        visual.set("contype", "0")
        visual.set("density", "0")
        visual.set("group", "1")

    @classmethod
    def from_xml(cls, xml: ET.Element) -> "VisualLink":
        """
        Create a visual link from an XML element.

        Args:
            xml: The XML element to create the visual link from.

        Returns:
            The visual link created from the XML element.

        Examples:
            >>> xml = ET.Element('visual')
            >>> VisualLink.from_xml(xml)
            VisualLink(name='visual', origin=None, geometry=None, material=None)
        """
        name = xml.get("name")

        origin_element = xml.find("origin")
        origin = Origin.from_xml(origin_element) if origin_element is not None else None

        geometry_element = xml.find("geometry")
        geometry = set_geometry_from_xml(geometry_element) if geometry_element is not None else None

        material_element = xml.find("material")
        material = Material.from_xml(material_element) if material_element is not None else None
        return cls(name=name, origin=origin, geometry=geometry, material=material)

from_xml(xml) classmethod

Create a visual link from an XML element.

Parameters:

Name	Type	Description	Default
xml	Element	The XML element to create the visual link from.	required

Returns:

Type	Description
VisualLink	The visual link created from the XML element.

Examples:

>>> xml = ET.Element('visual')
>>> VisualLink.from_xml(xml)
VisualLink(name='visual', origin=None, geometry=None, material=None)

Source code in onshape_robotics_toolkit\models\link.py

@classmethod
def from_xml(cls, xml: ET.Element) -> "VisualLink":
    """
    Create a visual link from an XML element.

    Args:
        xml: The XML element to create the visual link from.

    Returns:
        The visual link created from the XML element.

    Examples:
        >>> xml = ET.Element('visual')
        >>> VisualLink.from_xml(xml)
        VisualLink(name='visual', origin=None, geometry=None, material=None)
    """
    name = xml.get("name")

    origin_element = xml.find("origin")
    origin = Origin.from_xml(origin_element) if origin_element is not None else None

    geometry_element = xml.find("geometry")
    geometry = set_geometry_from_xml(geometry_element) if geometry_element is not None else None

    material_element = xml.find("material")
    material = Material.from_xml(material_element) if material_element is not None else None
    return cls(name=name, origin=origin, geometry=geometry, material=material)

to_mjcf(root)

Convert the visual properties to an MuJoCo compatible XML element.

Parameters:

Name	Type	Description	Default
root	Element	The root element to append the visual properties to.	required

Returns:

Type	Description
None	The XML element representing the visual properties.

Examples:

>>> visual = VisualLink(origin=Origin(...), geometry=BoxGeometry(...), material=Material(...))
>>> visual.to_mjcf()
<Element 'visual' at 0x7f8b3c0b4c70>

Source code in onshape_robotics_toolkit\models\link.py

def to_mjcf(self, root: ET.Element) -> None:
    """
    Convert the visual properties to an MuJoCo compatible XML element.

    Args:
        root: The root element to append the visual properties to.

    Returns:
        The XML element representing the visual properties.

    Examples:
        >>> visual = VisualLink(origin=Origin(...), geometry=BoxGeometry(...), material=Material(...))
        >>> visual.to_mjcf()
        <Element 'visual' at 0x7f8b3c0b4c70>
    """
    visual = root if root.tag == "geom" else ET.SubElement(root, "geom")
    visual.set("name", self.name)
    # TODO: Parent body uses visual origin, these share the same?
    self.origin.to_mjcf(visual)

    if self.geometry:
        self.geometry.to_mjcf(visual)

    self.material.to_mjcf(visual)

    visual.set("conaffinity", "0")
    visual.set("condim", "1")
    visual.set("contype", "0")
    visual.set("density", "0")
    visual.set("group", "1")

to_xml(root=None)

Convert the visual properties to an XML element.

Parameters:

Name	Type	Description	Default
root	Optional[Element]	The root element to append the visual properties to.	None

Returns:

Type	Description
Element	The XML element representing the visual properties.

Examples:

>>> visual = VisualLink(origin=Origin(...), geometry=BoxGeometry(...), material=Material(...))
>>> visual.to_xml()
<Element 'visual' at 0x7f8b3c0b4c70>

Source code in onshape_robotics_toolkit\models\link.py

def to_xml(self, root: Optional[ET.Element] = None) -> ET.Element:
    """
    Convert the visual properties to an XML element.

    Args:
        root: The root element to append the visual properties to.

    Returns:
        The XML element representing the visual properties.

    Examples:
        >>> visual = VisualLink(origin=Origin(...), geometry=BoxGeometry(...), material=Material(...))
        >>> visual.to_xml()
        <Element 'visual' at 0x7f8b3c0b4c70>
    """
    visual = ET.Element("visual") if root is None else ET.SubElement(root, "visual")
    visual.set("name", self.name)
    self.origin.to_xml(visual)
    self.geometry.to_xml(visual)
    self.material.to_xml(visual)
    return visual

transform(transformation_matrix)

Apply a transformation to the visual link's origin.

Parameters:

Name	Type	Description	Default
transformation_matrix	ndarray	A 4x4 transformation matrix (homogeneous).	required

Source code in onshape_robotics_toolkit\models\link.py

def transform(self, transformation_matrix: np.ndarray) -> None:
    """
    Apply a transformation to the visual link's origin.

    Args:
        transformation_matrix (np.ndarray): A 4x4 transformation matrix (homogeneous).
    """
    # Apply translation and rotation to the origin position
    pos = np.array([self.origin.xyz[0], self.origin.xyz[1], self.origin.xyz[2], 1])
    new_pos = transformation_matrix @ pos
    self.origin.xyz = tuple(new_pos[:3])  # Update position

    # Extract the rotation from the transformation matrix
    rotation_matrix = transformation_matrix[:3, :3]
    current_rotation = R.from_euler("xyz", self.origin.rpy)
    new_rotation = R.from_matrix(rotation_matrix @ current_rotation.as_matrix())
    self.origin.rpy = new_rotation.as_euler("xyz").tolist()