Struct HPChain 

pub struct HPChain<const N: usize> { /* private fields */ }

Precomputed Hayati-Paul chain with SoA layout.

Convention: T_i = Rz(θ) · Rx(α) · Ry(β) · Tx(a) · Tz(d)

HP adds a β rotation about Y, which makes it numerically stable for nearly-parallel consecutive joint axes where standard DH is singular.

Implementations

impl<const N: usize> HPChain<N>

pub const fn new(joints: [HPJoint; N]) -> Self

pub const fn from_hp(h: &[[f32; N]; 3], p: &[[f32; N]; 3]) -> Self

Construct from the row-major HP_H and HP_P const arrays emitted by the workcell macro.

h: [[f64; N]; 3] — rows are (x, y, z) components across joints. p: [[f64; N]; 3] — rows are (x, y, z) components across points.

Each h[_][i] is joint i’s axis in the base frame at zero config. p[_][0] is the base-to-joint-0 offset; p[_][i] for 1..N is the offset from joint i-1’s origin to joint i’s origin. The tool offset from joint N-1 to the flange is not part of this input because HPChain has no end-effector slot — wrap the result in a TransformedFK if a tool offset is required.

theta_offset is set to zero for every joint: at zero config each local x-axis is pinned to Rx(α) · Ry(β) · [1, 0, 0] expressed in the parent frame.

Trait Implementations

impl<const N: usize> Clone for HPChain<N>

fn clone(&self) -> HPChain<N>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<const N: usize> Debug for HPChain<N>

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

Formats the value using the given formatter.

impl<const N: usize> FKChain<N> for HPChain<N>

type Error = DekeError

fn fk(&self, q: &SRobotQ<N>) -> Result<[Affine3A; N], Self::Error>

fn fk_end(&self, q: &SRobotQ<N>) -> Result<Affine3A, Self::Error>

fn joint_axes_positions( &self, q: &SRobotQ<N>, ) -> Result<([Vec3A; N], [Vec3A; N], Vec3A), Self::Error>

Returns joint rotation axes and axis-origin positions in world frame at configuration q, plus the end-effector position.

fn dof(&self) -> usize

fn base_tf(&self) -> Affine3A

Configuration-independent transform from the robot’s base frame to the world frame. Defaults to identity; wrappers that install a static prefix (e.g. TransformedFK with a prefix set, or URDFChain with fixed leading joints baked in) override this so downstream consumers (collision validators, visualizers) can place the static base body at the correct pose.

fn max_reach(&self) -> Result<f32, Self::Error>

Theoretical maximum reach: sum of link lengths (upper bound, ignores joint limits).

fn jacobian(&self, q: &SRobotQ<N>) -> Result<[[f32; N]; 6], Self::Error>

Geometric Jacobian (6×N) at configuration q. Rows 0–2: linear velocity, rows 3–5: angular velocity.

fn jacobian_dot( &self, q: &SRobotQ<N>, qdot: &SRobotQ<N>, ) -> Result<[[f32; N]; 6], Self::Error>

First time-derivative of the geometric Jacobian.

fn jacobian_ddot( &self, q: &SRobotQ<N>, qdot: &SRobotQ<N>, qddot: &SRobotQ<N>, ) -> Result<[[f32; N]; 6], Self::Error>

Second time-derivative of the geometric Jacobian.

impl From<HPChain<1>> for DynamicHPChain

fn from(chain: HPChain<1>) -> Self

Converts to this type from the input type.

impl From<HPChain<2>> for DynamicHPChain

fn from(chain: HPChain<2>) -> Self

Converts to this type from the input type.

impl From<HPChain<3>> for DynamicHPChain

fn from(chain: HPChain<3>) -> Self

Converts to this type from the input type.

impl From<HPChain<4>> for DynamicHPChain

fn from(chain: HPChain<4>) -> Self

Converts to this type from the input type.

impl From<HPChain<5>> for DynamicHPChain

fn from(chain: HPChain<5>) -> Self

Converts to this type from the input type.

impl From<HPChain<6>> for DynamicHPChain

fn from(chain: HPChain<6>) -> Self

Converts to this type from the input type.

impl From<HPChain<7>> for DynamicHPChain

fn from(chain: HPChain<7>) -> Self

Converts to this type from the input type.

impl From<HPChain<8>> for DynamicHPChain

fn from(chain: HPChain<8>) -> Self

Converts to this type from the input type.