#include <CCrowfootMath.h>

Collaboration diagram for CCrowfootMath:

Classes
struct	LineDef
	Defines a line connected between the collecting point of the crowfoot and a fastening position. More...

struct	VisualSpec

Public Member Functions
	CCrowfootMath (double maxLineForce=1.0e7, const VisualSpec &visualSpec=VisualSpec())
	The default constructor does nothing. More...

int	AddLine (double length, const double *const fasteningpos)
	Adds a line to the collecting point. A line is added to the collecting point, the position of the other end of this line, as well as the length of the line may be moved between time steps. The returned integer is the index of the line, which is used for changing the other position and the length of the line later. More...

void	Update (const double const F, double const posOut)
	Calculates the position of the collecting point and the forces in each attached line. The forces in each line are found using the GetLineForce() method or the GetLineTension() method. More...

void	CalcIterativePos (const double const F, double const posOut, int maxNumIter=500, double expectedLengthToGo=3.0, double tolerance=0.00001)
	Calculates the position of the collecting point using an iterative method This method is for test purposes only. More...

void	GetLineForce (double *F, int lineIndex)
	Gets the force on the fastening point for a given line. The line index should be that returned from the AddLine method. More...

double	GetLineTension (int lineIndex)
	Gets the tension in the given line. The line index should be that returned from the AddLine method. More...

void	UpdateLineLength (double length, int lineIndex)
	Updates the length of a given line. The line index should be that returned from the AddLine method. More...

void	UpdateLineFasteningPos (const double *const fasteningpos, int lineIndex)
	Updates the "other" end position of a given line. The line index should be that returned from the AddLine method. More...

int	NumLines ()
	Gets the number of lines attached to the collecting point.

Protected Member Functions
void	CalcForOneLine (const Eigen::Vector3d &Force, const Eigen::Vector3d &ForceDir, double *const posOut)
	Calculates the collecting position and line force if the system is comprised of one line.

void	CalcForTwoLines (const Eigen::Vector3d &Force, const Eigen::Vector3d &ForceDir, double *const posOut)
	Calculates the collecting position and line forces if the system is comprised of two lines.

void	CalcForThreeLines (const Eigen::Vector3d &, const Eigen::Vector3d &ForceDir, double *const posOut)
	Calculates the collecting position and line forces if the system is comprised of three lines.

Eigen::Vector3d	CalcPosForOneStretched (int index, const Eigen::Vector3d &ForceDir)
	Calculates the collecting position if only one line is stretched.

Eigen::Vector3d	CalcPosForTwoStretched (int index1, int index2, const Eigen::Vector3d &ForceDir)
	Calculates the collecting position if only two lines are stretched.

void	CalcForOneActive (int index, const Eigen::Vector3d &, const Eigen::Vector3d &pos, double *const posOut)
	Calculates the collecting position and line force if only one line is stretched.

void	CalcForTwoActive (int index1, int index2, const Eigen::Vector3d &Force, Eigen::Vector3d pos, double *const posOut)
	Calculates the collecting position and line force if only two lines are stretched.

void	SetPosition (double *const posOut, const Eigen::Vector3d &pos)
	Sets the position of the output array.

bool	EnsureLineIndexOk (int lineIndex)
	Checks if a line index is ok. Prints a warning if not.

bool	PointIsWithinLineReach (int index, const Eigen::Vector3d &connPos)
	Tests if a position is within the reach of a specified line.

Protected Attributes
std::vector< LineDef >	m_lines

std::vector< Eigen::Vector3d >	m_lineForces

double	m_maxLineForce

VisualSpec	m_visualSpec

Detailed Description

Author: Karl-Johan Reite

Utility class for finding the position of the collecting point of a crowfoot and the forces on each connected line.

A run-time selected number of lines (1, 2 or 3) are attached to each other in a collection point. These lines are specified in terms of their length and fastening position. In addition, external forces acting on the collection point is specified. All positions and forces must be given in the same, not necessarily inertial, coordinate system.

This class finds the stable position of the collecting point, based on the forces acting on the point. This is done based on a direct solution, disregarding any dynamics. If one or two lines are stretched, the solution is found using geometric considerations. If three lines are active, the solution is found based on the method described in "Reliable computation of the points of intersection of n spheres in R^n" by I.D. Coope (Received 7 August 2000)

Revision history:: 31.10.2013 KJR: Initial version.

Constructor & Destructor Documentation

◆ CCrowfootMath()

CCrowfootMath::CCrowfootMath	(	double	maxLineForce = `1.0e7`,
		const VisualSpec &	visualSpec = `VisualSpec()`
	)

This constructor controls the visualization of the crow foot.

Member Function Documentation

◆ AddLine()

int CCrowfootMath::AddLine	(	double	length,
		const double *const	fasteningpos
	)

Parameters

[in]	length	The length of the line.
[in]	fasteningpos	The posOut of the fastening point.

Returns: The index of the line, for later use by update functions.

◆ CalcIterativePos()

void CCrowfootMath::CalcIterativePos	(	const double *const	F,
		double *const	posOut,
		int	maxNumIter = `500`,
		double	expectedLengthToGo = `3.0`,
		double	tolerance = `0.00001`
	)

Parameters

[in]	F	The sum of external forces.
[out]	posOut	The calculated position of the collecting point.
[in]	maxNumIter	Max number of iterations
[in]	expectedLengthToGo	The expected length to go
[in]	tolerance	Tolerance for accepted convergence

◆ GetLineForce()

void CCrowfootMath::GetLineForce	(	double *	F,
		int	lineIndex
	)

Parameters

[in]	F	The force on the fastening point.
[in]	lineIndex	The index of the line.

◆ GetLineTension()

double CCrowfootMath::GetLineTension ( int lineIndex )

Parameters

[in] lineIndex The index of the line.

◆ Update()

void CCrowfootMath::Update	(	const double *const	F,
		double *const	posOut
	)

Parameters

[in]	F	The sum of external forces.
[out]	posOut	The calculated position of the collecting point.

◆ UpdateLineFasteningPos()

void CCrowfootMath::UpdateLineFasteningPos	(	const double *const	fasteningpos,
		int	lineIndex
	)

Parameters

[in]	fasteningpos	The position of the other end of the line.
[in]	lineIndex	The index of the line.

◆ UpdateLineLength()

void CCrowfootMath::UpdateLineLength	(	double	length,
		int	lineIndex
	)

Parameters

[in]	length	The relaxed length of the line.
[in]	lineIndex	The index of the line.

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

reloadrepos/fhsim_aquaculture/src/trawl/subroutines/CCrowfootMath.h

Classes

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ CCrowfootMath()

Member Function Documentation

◆ AddLine()

◆ CalcIterativePos()

◆ GetLineForce()

◆ GetLineTension()

◆ Update()

◆ UpdateLineFasteningPos()

◆ UpdateLineLength()