GroundCurve Class Reference

Detailed Description

Describes a parametric, flat and on-the-ground 2D curve.

It will be also referred as the reference curve.

In mathematical terms:

Let \( G(p) \) be a curve that maps \( p, p0, p1 ∈ ℝ / p ⊂ [p0, p1] ∧ p >= 0 \), to the \( (x, y) \) space, i.e. ℝ² in the INERTIAL Frame. Its arc-length is \( L \) and the heading of the tangent vector in the INERTIAL Frame is \( θ \). \( G(p) \) is G¹ in the domain of \( p \).

There exist:

• \( G(p) \mapsto ℝ² \).
• \( G'(p) \mapsto ℝ² \).
• \( θ(p) \mapsto [-π; π] \).
• \( θ'(p) \mapsto [-π; π] \) where \( θ' \) is the derivative of the heading with respect to \( p \).
• \( G⁻¹(x, y) \mapsto [p0, p1] \), where \( G⁻¹\) is the inverse function of \( G \).

#include <src/maliput_malidrive/road_curve/ground_curve.h>

Inheritance diagram for GroundCurve:

Public Member Functions
	MALIDRIVE_NO_COPY_NO_MOVE_NO_ASSIGN (GroundCurve)
virtual	~GroundCurve ()=default
double	PFromP (double xodr_p) const
	Calculates the \( p \) value that matches with the \( p \) value in the XODR description. More...
maliput::math::Vector2	G (double p) const
	Evaluates \( G(p) \). More...
maliput::math::Vector2	GDot (double p) const
	Evaluates \( G'(p) \). More...
double	Heading (double p) const
	Evaluates \( θ(p) \). More...
double	HeadingDot (double p) const
	Evaluates \( θ'(p) \). More...
double	GInverse (const maliput::math::Vector2 &xy) const
	Evaluates \( G⁻¹(x, y) \). More...
double	ArcLength () const
double	linear_tolerance () const
double	p0 () const
double	p1 () const
bool	IsG1Contiguous () const

Static Public Attributes
static constexpr double	kEpsilon = 1e-13
	Implementations may opt to allow a tolerance or be up to kEpsilon away from [p0(); p1()]. More...

Protected Member Functions
	GroundCurve ()=default

Constructor & Destructor Documentation

~GroundCurve()

virtual ~GroundCurve ( )

virtualdefault

GroundCurve()

GroundCurve ( )

protecteddefault

Member Function Documentation

ArcLength()

double ArcLength

(

)

const

Returns

The arc-length of \( G(p) \) in the range \( [`p0()`; `p1()`] \).

G()

maliput::math::Vector2 G

(

double

p

)

const

Evaluates \( G(p) \).

Parameters

p	The parameter. It must be in the range \( [`p0()`; `p1()`] \).

Exceptions

maliput::common::assertion_error

When p is not in \( [`p0()`; `p1()`] \).

Returns

The image of \( G(p) \).

GDot()

maliput::math::Vector2 GDot

(

double

p

)

const

Evaluates \( G'(p) \).

Parameters

p	The parameter. It must be in the range \( [`p0()`; `p1()`] \).

Exceptions

maliput::common::assertion_error

When p is not in \( [`p0()`; `p1()`] \).

Returns

The image of \( G'(p) \), i.e. the tangent vector.

GInverse()

double GInverse

(

const maliput::math::Vector2 &

xy

)

const

Evaluates \( G⁻¹(x, y) \).

Parameters

xy	A point in ℝ² that is used as a point in the domain of \( G⁻¹ \). When it does not belong to the domain of the inverse function, a point that minimizes its distance is used instead.

Returns

The p parameter that would minimize the Euclidean distance of G(p) to xy.

Heading()

double Heading

(

double

p

)

const

Evaluates \( θ(p) \).

Parameters

p	The parameter. It must be in the range \( [`p0()`; `p1()`] \).

Exceptions

maliput::common::assertion_error

When p is not in \( [`p0()`; `p1()`] \).

Returns

The heading of \( G(p) \) at p.

HeadingDot()

double HeadingDot

(

double

p

)

const

Evaluates \( θ'(p) \).

Parameters

p	The parameter. It must be in the range \( [`p0()`; `p1()`] \).

Exceptions

maliput::common::assertion_error

When p is not in \( [`p0()`; `p1()`] \).

Returns

The derivative of the heading of \( G(p) \) at p.

IsG1Contiguous()

bool IsG1Contiguous

(

)

const

Returns

True when \( F(p) \) is G¹ in the interval \( [`p0()`; `p1()`] \).

linear_tolerance()

double linear_tolerance

(

)

const

Returns

The linear tolerance used by implementations to adapt to maliput::api::RoadGeometry requirements.

MALIDRIVE_NO_COPY_NO_MOVE_NO_ASSIGN()

MALIDRIVE_NO_COPY_NO_MOVE_NO_ASSIGN

(

GroundCurve

)

p0()

double p0

(

)

const

Returns

The lower bound range of \( p \).

p1()

double p1

(

)

const

Returns

The upper bound range of \( p \).

PFromP()

double PFromP

(

double

xodr_p

)

const

Calculates the \( p \) value that matches with the \( p \) value in the XODR description.

Parameters

xodr_p

The parameter in the XODR description.

Returns

The \( p \) value in the GroundCurve domain.

Exceptions

maliput::common::assertion_error

When xodr_p doesn't match to any parameter value in the XODR domain.

Member Data Documentation

kEpsilon

constexpr double kEpsilon = 1e-13

staticconstexpr

Implementations may opt to allow a tolerance or be up to kEpsilon away from [p0(); p1()].

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

• ground_curve.h