referencePathFrenet
Smooth reference path fit to waypoints
Description
The referencePathFrenet
object fits a smooth, piecewise,
continuous curve to a set of waypoints given as [x y]
or [x y
theta]
. After fitting, points along the curve, the path points are expressed as
[x y theta kappa dkappa s]
, where:
x
y
andtheta
— SE(2) state expressed in global coordinates, withx
andy
in meters andtheta
in radianskappa
— Curvature, or inverse of the radius, in metersdkappa
— Derivative of curvature with respect to arc length in meters per seconds
— Arc length, or distance along path from path origin, in meters
Using this object, convert trajectories between global and Frenet coordinate systems, interpolate states along the path based on arc length, and query the closest point on a path from a global state.
The object expresses Frenet states as a vector of form [S dS ddS L dL
ddL]
, where S
is the arc length and L
is the
perpendicular deviation from the direction of the reference path. Derivatives of
S
are relative to time. Derivatives of L
are relative
to the arc length, S
.
Creation
Syntax
Description
refPathObj = referencePathFrenet(
fits a piecewise, continuous set of curves to the specified waypoints. The
waypoints
)waypoints
argument sets the Waypoints
property.
refPathObj = referencePathFrenet(
fits a piecewise, continuous set of curves to waypoints using the specified distance
between interpolated path points. The waypoints
,'DiscretizationDistance',discretionDist)discretionDist
argument sets
the DiscretizationDistance
property.
Properties
Object Functions
closestPoint | Find closest point on reference path to global point |
closestPointsToSequence | Projects sequence of points onto path |
closestProjections | Find orthogonal projections between path tangent vector and query point |
curvature | Return curvature at arclength |
changeInCurvature | Return change-in-curvature at arclength |
frenet2global | Convert Frenet states to global states |
global2frenet | Convert global states to Frenet states |
interpolate | Interpolate reference path at provided arc lengths |
position | Return xy-position at arclength |
tangentAngle | Return tangent angle at arclength |
show | Display reference path in figure |
Examples
Extended Capabilities
Version History
Introduced in R2020b