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Line

Class that implements a 3D line section. More...

#include <Line.h>

Inherits from PathSection

Public Functions

Name
Line(Eigen::Vector3d start_point, Eigen::Vector3d end_point)
Constructor for the 3DLine class. It assumes that the reference for the frame is (0, 0, 0)
Line(Eigen::Vector3d start_point, Eigen::Vector3d end_point, Eigen::Vector3d ref_point)
Constructor for the 3DLine class.
virtual Eigen::Vector3d eq_pd(double t) override
Path section equation.
virtual Eigen::Vector3d eq_d_pd(double t) override
First derivative of the path section equation with respect to the path parameter t.
virtual Eigen::Vector3d eq_dd_pd(double t) override
Second derivative of the path section equation with respect to the path parameter t.
virtual double curvature(double t) override
The curvature of a line is constant, therefore we can make the computation really efficient.
virtual double getClosestPointGamma(Eigen::Vector3d & coordinate) override
Method for getting the gamma of the closes point to the path in a more efficient manner For a line it uses a closed form equation to solve this problem.

Additional inherited members

Public Functions inherited from PathSection

Name
virtual double tangent(double t)
Default method for computing the tangent to the path section.
virtual double derivative_norm(double t)
Default method for computing the norm of the derivative.
bool can_be_composed()
Method to return whether a pathSection can be composed with other path sections or not.
double limitGamma(double t)
Method to limit the gamma between the minimum and maximum value By default the maximum gamma is a very high number.
double getMaxGammaValue()
Method used to get the maximum gamma allowed by the path section By the default is the maximum valid number possible in c++.
double getMinGammaValue()
Method used to get the minimum gamma allowed by the path section By default is the minimum valid number possible in c++.
virtual ~PathSection()
Virtual destructor for the abstract class.

Protected Functions inherited from PathSection

Name
PathSection(bool can_be_composed)
Constructor for the abstract class i NOTE: this class is virtual, therefore an object of type PathSection cannot be instantiated in memory. Only derivatives of the class PathSection.
bool setMaxGammaValue(double gamma_max)
Method to update the max of the gamma parameter Validates if the value received is greater than gamma_min.
bool setMinGammaValue(double gamma_min)
Method to update the min value of the gamma parameter Validades if the value is received is smaller than gamma_max.
double GradientDescent(double gamma_o, Eigen::Vector3d & x_pos, double tolerance)
Method that implements the gradient descent to minimize the error of
double getInitialGammaEstimate(Eigen::Vector3d & x_pos, int num_partitions, double min_val, double max_val)
Method to get an initial estimate for the gamma. It divides the section into n sections and search for local minimums in the function that computes the distance of the vehicle inside those sections.
double bisection(Eigen::Vector3d & x_pos, double a, double b)
Method to implement bisection method

Detailed Description

class Line;

Class that implements a 3D line section.

Author:

  • Marcelo Jacinto
  • Joao Quintas
  • Joao Cruz
  • Hung Tuan

Version: 1.0a

Date: 2021

Copyright: MIT

This class is used as a part of the sections library

Public Functions Documentation

function Line

Line(
    Eigen::Vector3d start_point,
    Eigen::Vector3d end_point
)

Constructor for the 3DLine class. It assumes that the reference for the frame is (0, 0, 0)

Parameters:

  • start_point The starting point in the 3D space
  • end_point The end point in the 3D space

function Line

Line(
    Eigen::Vector3d start_point,
    Eigen::Vector3d end_point,
    Eigen::Vector3d ref_point
)

Constructor for the 3DLine class.

Parameters:

  • start_point The starting point in the 3D space
  • end_point The end point in the 3D space
  • ref_point The ref_point in the 3D to draw the line relative to this reference

function eq_pd

virtual Eigen::Vector3d eq_pd(
    double t
) override

Path section equation.

Parameters:

  • t The path parameter

Return: An Eigen::Vector3d with the value of the equation of the path

Reimplements: PathSection::eq_pd

function eq_d_pd

virtual Eigen::Vector3d eq_d_pd(
    double t
) override

First derivative of the path section equation with respect to the path parameter t.

Parameters:

  • t The path parameter

Return: An Eigen::Vector3d with the value of the derivative of the path equation

Reimplements: PathSection::eq_d_pd

function eq_dd_pd

virtual Eigen::Vector3d eq_dd_pd(
    double t
) override

Second derivative of the path section equation with respect to the path parameter t.

Parameters:

  • t The path parameter

Return: An Eigen::Vector3d with the value of the second derivative of the path equation

Reimplements: PathSection::eq_dd_pd

function curvature

virtual double curvature(
    double t
) override

The curvature of a line is constant, therefore we can make the computation really efficient.

Parameters:

  • t The path parameter

Return: A double = 0 (since a line has no curvature)

Reimplements: PathSection::curvature

function getClosestPointGamma

virtual double getClosestPointGamma(
    Eigen::Vector3d & coordinate
) override

Method for getting the gamma of the closes point to the path in a more efficient manner For a line it uses a closed form equation to solve this problem.

Parameters:

  • coordinate The vehicle coordinate

Return: A double with the gamma corresponding to the cloest point in the path.

Reimplements: PathSection::getClosestPointGamma

Updated on 2022-09-15 at 17:51:30 +0000

Last update: September 15, 2022
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