Struct Joint 

pub struct Joint {
    pub joint_type: JointType,
    pub parent_to_joint: SpatialTransform,
    pub axis: Vec3,
    pub damping: f64,
    pub limits: Option<[f64; 2]>,
}

A joint connecting two bodies.

Fields

joint_type: JointType

Joint type.

parent_to_joint: SpatialTransform

Transform from parent body frame to joint frame (constant).

axis: Vec3

Joint axis in local frame (for revolute: typically Z).

damping: f64

Damping coefficient.

limits: Option<[f64; 2]>

Joint position limits [lower, upper] (None = unlimited).

Implementations

impl Joint

pub fn revolute(parent_to_joint: SpatialTransform) -> Self

Create a revolute joint with the given parent-to-joint transform.

pub fn prismatic(parent_to_joint: SpatialTransform, axis: Vec3) -> Self

Create a prismatic joint with the given parent-to-joint transform and axis.

pub fn spherical(parent_to_joint: SpatialTransform) -> Self

Create a spherical (ball) joint with the given parent-to-joint transform.

pub fn free(parent_to_joint: SpatialTransform) -> Self

Create a free joint with the given parent-to-joint transform.

pub fn fixed(parent_to_joint: SpatialTransform) -> Self

Create a fixed joint (rigid attachment).

pub fn ndof(&self) -> usize

Number of degrees of freedom for this joint type.

pub fn joint_transform_slice(&self, q: &[f64]) -> SpatialTransform

Compute the joint transform for the given joint position(s).

Returns the Plücker transform from predecessor to successor frame. q slice should have length >= ndof().

pub fn joint_transform(&self, q: f64) -> SpatialTransform

Compute the joint transform for a single-DOF joint (backward compat). For multi-DOF joints, use joint_transform_slice instead.

pub fn motion_subspace_matrix(&self) -> DMat

Motion subspace matrix S for this joint. Returns a matrix of size 6 × ndof. For single-DOF joints, returns a 6×1 column vector.

pub fn motion_subspace(&self) -> SpatialVec

Motion subspace for single-DOF joints (backward compat). For multi-DOF joints, use motion_subspace_matrix instead. Fixed joints return a zero vector.

Trait Implementations

impl Clone for Joint

fn clone(&self) -> Joint

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Joint

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.