frc::SplineHelper Class Reference

Helper class that is used to generate cubic and quintic splines from user provided waypoints. More...

#include <frc/spline/SplineHelper.h>

Static Public Member Functions
static wpi::array< Spline< 3 >::ControlVector, 2 >	CubicControlVectorsFromWaypoints (const Pose2d &start, const std::vector< Translation2d > &interiorWaypoints, const Pose2d &end)
	Returns 2 cubic control vectors from a set of exterior waypoints and interior translations. More...
static std::vector< QuinticHermiteSpline >	QuinticSplinesFromWaypoints (const std::vector< Pose2d > &waypoints)
	Returns quintic splines from a set of waypoints. More...
static std::vector< CubicHermiteSpline >	CubicSplinesFromControlVectors (const Spline< 3 >::ControlVector &start, std::vector< Translation2d > waypoints, const Spline< 3 >::ControlVector &end)
	Returns a set of cubic splines corresponding to the provided control vectors. More...
static std::vector< QuinticHermiteSpline >	QuinticSplinesFromControlVectors (const std::vector< Spline< 5 >::ControlVector > &controlVectors)
	Returns a set of quintic splines corresponding to the provided control vectors. More...
static std::vector< QuinticHermiteSpline >	OptimizeCurvature (const std::vector< QuinticHermiteSpline > &splines)
	Optimizes the curvature of 2 or more quintic splines at knot points. More...

Detailed Description

Helper class that is used to generate cubic and quintic splines from user provided waypoints.

Member Function Documentation

CubicControlVectorsFromWaypoints()

static wpi::array< Spline< 3 >::ControlVector, 2 > frc::SplineHelper::CubicControlVectorsFromWaypoints ( const Pose2d &  start, const std::vector< Translation2d > &  interiorWaypoints, const Pose2d &  end  )

static

Returns 2 cubic control vectors from a set of exterior waypoints and interior translations.

Parameters

start	The starting pose.
interiorWaypoints	The interior waypoints.
end	The ending pose.

Returns

2 cubic control vectors.

CubicSplinesFromControlVectors()

static std::vector< CubicHermiteSpline > frc::SplineHelper::CubicSplinesFromControlVectors ( const Spline< 3 >::ControlVector &  start, std::vector< Translation2d >  waypoints, const Spline< 3 >::ControlVector &  end  )

static

Returns a set of cubic splines corresponding to the provided control vectors.

The user is free to set the direction of the start and end point. The directions for the middle waypoints are determined automatically to ensure continuous curvature throughout the path.

The derivation for the algorithm used can be found here: https://www.uio.no/studier/emner/matnat/ifi/nedlagte-emner/INF-MAT4350/h08/undervisningsmateriale/chap7alecture.pdf

Parameters

start	The starting control vector.
waypoints	The middle waypoints. This can be left blank if you only wish to create a path with two waypoints.
end	The ending control vector.

Returns

A vector of cubic hermite splines that interpolate through the provided waypoints.

OptimizeCurvature()

static std::vector< QuinticHermiteSpline > frc::SplineHelper::OptimizeCurvature ( const std::vector< QuinticHermiteSpline > &  splines )

static

Optimizes the curvature of 2 or more quintic splines at knot points.

Overall, this reduces the integral of the absolute value of the second derivative across the set of splines.

Parameters

splines

A vector of un-optimized quintic splines.

Returns

A vector of optimized quintic splines.

QuinticSplinesFromControlVectors()

static std::vector< QuinticHermiteSpline > frc::SplineHelper::QuinticSplinesFromControlVectors ( const std::vector< Spline< 5 >::ControlVector > &  controlVectors )

static

Returns a set of quintic splines corresponding to the provided control vectors.

The user is free to set the direction of all waypoints. Continuous curvature is guaranteed throughout the path.

Parameters

controlVectors

The control vectors.

Returns

A vector of quintic hermite splines that interpolate through the provided waypoints.

QuinticSplinesFromWaypoints()

static std::vector< QuinticHermiteSpline > frc::SplineHelper::QuinticSplinesFromWaypoints ( const std::vector< Pose2d > &  waypoints )

static

Returns quintic splines from a set of waypoints.

Parameters

waypoints

The waypoints

Returns

List of quintic splines.

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The documentation for this class was generated from the following file:

• frc/spline/SplineHelper.h