A cylindrical rod. More...

#include <Rod.hpp>

Inheritance diagram for moordyn::Rod:

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Collaboration diagram for moordyn::Rod:

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Public Types
enum	types { COUPLED = -2 , CPLDPIN = -1 , FREE = 0 , PINNED = 1 , FIXED = 2 , VESSEL = COUPLED , VESPIN = CPLDPIN , POINT = FREE , ANCHOR = FIXED }
	Types of rods. More...

Public Member Functions
	Rod (moordyn::Log *log, size_t rodId)
	Costructor. More...

	~Rod ()
	Destructor.

void	setup (int number, types type, RodProps *props, vec6 endCoords, unsigned int n, EnvCondRef env_in, shared_ptr< ofstream > outfile, string channels)
	Setup a rod. More...

void	addLine (Line *line, EndPoints line_end_point, EndPoints rod_end_point)
	Attach a line endpoint to the rod end point A. More...

EndPoints	removeLine (EndPoints end_point, Line *line)
	Dettach a line. More...

void	setWaves (moordyn::WavesRef waves_in, moordyn::SeafloorRef seafloor_in)
	Set the environmental data. More...

void	openoutput ()
	Opens rod output file.

std::pair< XYZQuat, vec6 >	initialize ()
	Initialize the rod state. More...

void	initialize (InstanceStateVarView r)
	Initialize a free instance. More...

unsigned int	getN () const
	Number of segments. More...

vec	getNodePos (unsigned int i) const
	Get the position of a node. More...

vec	getNodeVel (unsigned int i) const
	Get the velocity of a node. More...

real	GetRodOutput (OutChanProps outChan)
	Get rod output. More...

std::pair< real, real >	getDrag () const
	Get the drag coefficients. More...

void	setDrag (real cdn, real cdt)
	Set the drag coefficients. More...

void	scaleDrag (real scaler)
	Scale the drag coefficients. More...

void	setTime (real time)
	Set the line simulation time. More...

void	getState (XYZQuat &pos, vec6 &vel) const
	Get the body kinematics. More...

std::pair< XYZQuat, vec6 >	getState () const
	Get the body kinematics. More...

Public Member Functions inherited from moordyn::Instance
	Instance (moordyn::Log *log)
	Costructor. More...

virtual	~Instance ()=default
	Destructor.

const size_t	id () const
	Get the unique identifier of this instance. More...

Public Member Functions inherited from moordyn::io::IO
	IO (moordyn::Log *log)
	Costructor. More...

virtual	~IO ()=default
	Destructor.

void	Save (const std::string filepath)
	Save the entity into a file. More...

void	Load (const std::string filepath)
	Loads the entity from a file. More...

Public Member Functions inherited from moordyn::LogUser
	LogUser (Log *log=NULL)
	Constructor. More...

	~LogUser ()
	Destructor.

void	SetLogger (Log *log)
	Set the log handler. More...

Log *	GetLogger () const
	Get the log handler. More...

Static Public Member Functions
static string	TypeName (types t)
	Return a string with the name of a type. More...

Public Attributes
size_t	rodId
	Rod ID.

int	number
	Rod number.

types	type
	Rod type.

real	roll
	The roll angle (useful for output)

real	pitch
	The pitch angle (useful for output)

void	setState (const InstanceStateVarView r)
	Set the rod state. More...

void	initiateStep (vec6 r, vec6 rd, vec6 rdd)
	Called at the beginning of each coupling step to update the boundary conditions (rod kinematics) for the proceeding time steps. More...

vec6	getUnfreeVel () const
	Get the last setted velocity for an unfree rod. More...

void	updateFairlead (real time)
	Sets the kinematics. More...

void	setKinematics (vec6 r, vec6 rd)
	Take the kinematics from the fairlead information. More...

void	setDependentStates ()
	Set the end kinematics then set the states (positions and velocities) of any line ends attached to this rod. More...

void	getStateDeriv (InstanceStateVarView drdt)
	calculate the forces and state derivatives of the rod More...

const vec6	getFnet () const
	Get the net force on rod (and possibly moment at end A if it's not pinned) More...

const mat6	getM () const
	Get the rod mass matrix. More...

void	getNetForceAndMass (vec6 &Fnet_out, mat6 &M_out, vec rBody, vec6 vBody)
	Calculate the force and mass contributions of the point on the parent body. More...

void	getNetForceAndMass (vec6 &Fnet_out, mat6 &M_out)
	Calculate the force and mass contributions of the point on the parent body. More...

void	doRHS ()
	This is the big function that calculates the forces on the rod, including from attached lines. More...

void	Output (real)

const size_t	stateN () const
	Get the number of state variables required by this instance. More...

const size_t	stateDims () const
	Get the dimension of the state variable. More...

std::vector< uint64_t >	Serialize (void)
	Produce the packed data to be saved. More...

uint64_t *	Deserialize (const uint64_t *data)
	Unpack the data to restore the Serialized information. More...

void	saveVTK (const char *filename)
	Save the rod on a VTK (.vtp) file. More...

const leanvtk::VTPWriter *	getVTK () const
	Get the VTK writer. More...

Additional Inherited Members
Protected Member Functions inherited from moordyn::io::IO
ofstream	MakeFile (const std::string filepath) const
	Create an output file and write the MoorDyn magic header. More...

std::tuple< uint64_t, uint64_t * >	LoadFile (const std::string filepath) const
	Open an input file and load the data. More...

uint64_t	Serialize (const uint64_t &i)
	Pack an unsigned integer to make it writable. More...

uint64_t	Serialize (const int64_t &i)
	Pack an integer to make it writable. More...

uint64_t	Serialize (const real &f)
	Pack a float to make it writable. More...

std::vector< uint64_t >	Serialize (const vec &m)
	Pack a 3D vector to make it writable. More...

std::vector< uint64_t >	Serialize (const vec6 &m)
	Pack a 6D vector to make it writable. More...

std::vector< uint64_t >	Serialize (const mat &m)
	Pack a 3x3 matrix to make it writable. More...

std::vector< uint64_t >	Serialize (const mat6 &m)
	Pack a 6x6 matrix to make it writable. More...

std::vector< uint64_t >	Serialize (const quaternion &m)
	Pack a quaternion to make it writable. More...

std::vector< uint64_t >	Serialize (const XYZQuat &m)
	Pack an XYZQuat to make it writable. More...

std::vector< uint64_t >	Serialize (const std::vector< real > &l)
	Pack a list of floating point numbers to make it writable. More...

std::vector< uint64_t >	Serialize (const std::vector< vec > &l)
	Pack a list of 3D vectors to make it writable. More...

std::vector< uint64_t >	Serialize (const std::vector< vec6 > &l)
	Pack a list of 6D vectors to make it writable. More...

std::vector< uint64_t >	Serialize (const std::vector< mat > &l)
	Pack a list of 3x3 matrices to make it writable. More...

std::vector< uint64_t >	Serialize (const std::vector< mat6 > &l)
	Pack a list of 6x6 matrices to make it writable. More...

std::vector< uint64_t >	Serialize (const Eigen::Matrix< real, Eigen::Dynamic, Eigen::Dynamic > &l)
	Pack an arbitrarily large matrix. More...

template<typename T >
std::vector< uint64_t >	Serialize (const std::vector< std::vector< T >> &l)
	Pack a list of lists to make it writable This function might act recursively. More...

uint64_t *	Deserialize (const uint64_t *in, uint64_t &out)
	Unpack a loaded unsigned integer. More...

uint64_t *	Deserialize (const uint64_t *in, int64_t &out)
	Unpack a loaded integer. More...

uint64_t *	Deserialize (const uint64_t *in, real &out)
	Unpack a loaded floating point number. More...

uint64_t *	Deserialize (const uint64_t *in, vec &out)
	Unpack a loaded 3D vector. More...

uint64_t *	Deserialize (const uint64_t *in, vec6 &out)
	Unpack a loaded 6D vector. More...

uint64_t *	Deserialize (const uint64_t *in, mat &out)
	Unpack a loaded 3x3 matrix. More...

uint64_t *	Deserialize (const uint64_t *in, mat6 &out)
	Unpack a loaded 6x6 matrix. More...

uint64_t *	Deserialize (const uint64_t *in, quaternion &out)
	Unpack a loaded quaternion. More...

uint64_t *	Deserialize (const uint64_t *in, XYZQuat &out)
	Unpack a loaded XYZQuat. More...

uint64_t *	Deserialize (const uint64_t *in, std::vector< real > &out)
	Unpack a loaded list of floating point numbers. More...

uint64_t *	Deserialize (const uint64_t *in, std::vector< vec > &out)
	Unpack a loaded list of 3D vectors. More...

uint64_t *	Deserialize (const uint64_t *in, std::vector< vec6 > &out)
	Unpack a loaded list of 6D vectors. More...

uint64_t *	Deserialize (const uint64_t *in, std::vector< mat > &out)
	Unpack a loaded list of 3x3 matrices. More...

uint64_t *	Deserialize (const uint64_t *in, std::vector< mat6 > &out)
	Unpack a loaded list of 6x6 matrices. More...

uint64_t *	Deserialize (const uint64_t *in, Eigen::Matrix< real, Eigen::Dynamic, Eigen::Dynamic > &out)
	Unpack an arbitrarily large matrix. More...

template<typename T >
uint64_t *	Deserialize (const uint64_t *in, std::vector< std::vector< T >> &out)
	Unpack a loaded list of lists. More...

Protected Attributes inherited from moordyn::LogUser
Log *	_log
	The log handler.

Detailed Description

A cylindrical rod.

Rod are cylindrical structures with much more complete dynamics than moordyn::Body.

Each end point of the rod can be fixed or pinned to another object, let free or control it externally

Member Enumeration Documentation

◆ types

enum moordyn::Rod::types

Types of rods.

Enumerator
COUPLED	Is attached rigidly to a coupling point (6dof)
CPLDPIN	Is pinned to a coupling point (3dof)
FREE	Is free to move, controlled by MoorDyn.
PINNED	Is pinned to a fixed point (or a body/ptfm, in which case added to list?)
FIXED	Is attached rigidly to a fixed point (or a body/ptfm, in which case added to list?)

Constructor & Destructor Documentation

◆ Rod()

moordyn::Rod::Rod	(	moordyn::Log *	log,
		size_t	rodId
	)

Costructor.

Parameters

log	Logging handler
rodId	Unique identifier of this rod

Member Function Documentation

◆ addLine()

void moordyn::Rod::addLine	(	Line *	line,
		EndPoints	line_end_point,
		EndPoints	rod_end_point
	)

Attach a line endpoint to the rod end point A.

Parameters

line	The line to be attached
line_end_point	The line endpoint
rod_end_point	The rod endpoint

Exceptions

moordyn::invalid_value_error If the end points are not valid

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◆ Deserialize()

uint64_t * moordyn::Rod::Deserialize ( const uint64_t * data )

virtual

Unpack the data to restore the Serialized information.

This is the inverse of Serialize(void)

Parameters

data	The packed data

Returns: A pointer to the end of the file, for debugging purposes

Implements moordyn::io::IO.

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◆ doRHS()

void moordyn::Rod::doRHS ( )

This is the big function that calculates the forces on the rod, including from attached lines.

(-z1lo+Rodzeta(I))/abs(sinPhi) ! distance from node to waterline cross at same axial location [m]

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◆ getDrag()

std::pair<real, real> moordyn::Rod::getDrag ( ) const

inline

Get the drag coefficients.

Returns: The normal (transversal) and tangential (axial) drag coefficients

◆ getFnet()

const vec6 moordyn::Rod::getFnet ( ) const

Get the net force on rod (and possibly moment at end A if it's not pinned)

Returns: The net force

Exceptions

moordyn::invalid_value_error If the rod is not of type moordyn::Rod::COUPLED or moordyn::Rod::CPLDPIN

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◆ getM()

const mat6 moordyn::Rod::getM ( ) const

inline

Get the rod mass matrix.

Returns: The net force

Exceptions

moordyn::invalid_value_error If the rod is not of type moordyn::Rod::COUPLED or moordyn::Rod::CPLDPIN

◆ getN()

unsigned int moordyn::Rod::getN ( ) const

inline

Number of segments.

The number of nodes can be computed as moordyn::Rod::getN() + 1

Returns: The number of segments, moordyn::Rod::N

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◆ getNetForceAndMass() [1/2]

void moordyn::Rod::getNetForceAndMass	(	vec6 &	Fnet_out,
		mat6 &	M_out
	)

inline

Calculate the force and mass contributions of the point on the parent body.

Parameters

Fnet_out	Output Force about body ref point
M_out	Output Mass matrix about body ref point

◆ getNetForceAndMass() [2/2]

void moordyn::Rod::getNetForceAndMass	(	vec6 &	Fnet_out,
		mat6 &	M_out,
		vec	rBody,
		vec6	vBody
	)

Calculate the force and mass contributions of the point on the parent body.

Parameters

Fnet_out	Output Force about body ref point
M_out	Output Mass matrix about body ref point
rBody	The body position
vBody	The body velocity

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◆ getNodePos()

vec moordyn::Rod::getNodePos ( unsigned int i ) const

inline

Get the position of a node.

Parameters

i	The line node index

Returns: The position

Exceptions

invalid_value_error If the node index i is bigger than the number of nodes, moordyn::Line::N + 1

◆ getNodeVel()

vec moordyn::Rod::getNodeVel ( unsigned int i ) const

inline

Get the velocity of a node.

Parameters

i	The line node index

Returns: The velocity

Exceptions

invalid_value_error If the node index i is bigger than the number of nodes, moordyn::Line::N + 1

◆ GetRodOutput()

real moordyn::Rod::GetRodOutput ( OutChanProps outChan )

Get rod output.

This funtion is useful when outputs are set in the rod properties

Parameters

outChan The output channel/field

Returns: The output value, 0.0 if a non-valid field is set

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◆ getState() [1/2]

std::pair<XYZQuat, vec6> moordyn::Rod::getState ( ) const

inline

Get the body kinematics.

Returns: Position and velocity

◆ getState() [2/2]

void moordyn::Rod::getState	(	XYZQuat &	pos,
		vec6 &	vel
	)		const

inline

Get the body kinematics.

Parameters

pos	The output position
vel	The output velocity

◆ getStateDeriv()

void moordyn::Rod::getStateDeriv ( InstanceStateVarView drdt )

virtual

calculate the forces and state derivatives of the rod

Parameters

drdt	The velocity quaternion and the linear and angular accelerations

Exceptions

nan_error If nan values are detected in any node position

Note: The returned linear velocity and accelerations for pinned rods should be ignored

Implements moordyn::Instance.

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◆ getUnfreeVel()

vec6 moordyn::Rod::getUnfreeVel ( ) const

inline

Get the last setted velocity for an unfree rod.

For free rods the behaviour is undetermined

Returns: The velocity (6 dof)

◆ getVTK()

const leanvtk::VTPWriter* moordyn::Rod::getVTK ( ) const

inline

Get the VTK writer.

This function is useful for writing multiblock .vtm files

Returns: The VTK .vtp writer

◆ initialize() [1/2]

std::pair< XYZQuat, vec6 > moordyn::Rod::initialize ( )

Initialize the rod state.

Parameters

r	The output state variable

Returns: The position and orientation angles (first) and the linear and angular velocity (second)

Note: moordyn::Rod::r6 and moordyn::Rod::v6 must already be set; ground- or body-pinned rods have already had moordyn::Rod::setKinematics() called; In the case of pinned rods, just the rod directions and angular velocites shall be considered

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◆ initialize() [2/2]

void moordyn::Rod::initialize ( InstanceStateVarView r )

inlinevirtual

Initialize a free instance.

Parameters

r	The output state variable

Exceptions

moordyn::invalid_value_error If the instance does not have free states. e.g. a coupled body controlled from outside

Implements moordyn::Instance.

◆ initiateStep()

void moordyn::Rod::initiateStep	(	vec6	r,
		vec6	rd,
		vec6	rdd
	)

Called at the beginning of each coupling step to update the boundary conditions (rod kinematics) for the proceeding time steps.

Parameters

r	The input position
rd	The input velocity
rdd	The input acceleration

Exceptions

moordyn::invalid_value_error If the rod is not of type moordyn::Rod::COUPLED or moordyn::Rod::CPLDPIN

Note: If the rod is of type moordyn::Rod::CPLDPIN, then just 3 components of r and rd are considered

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◆ removeLine()

EndPoints moordyn::Rod::removeLine	(	EndPoints	end_point,
		Line *	line
	)

Dettach a line.

Parameters

end_point	The rod end point where the line is attached
line	The line

Returns: The line end point that was attached to the rod

Exceptions

moordyn::invalid_value_error If there is no an attached line with the provided lineID

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◆ saveVTK()

void moordyn::Rod::saveVTK ( const char * filename )

Save the rod on a VTK (.vtp) file.

Parameters

filename The output file name

Exceptions

output_file_error If the file cannot be saved

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◆ scaleDrag()

void moordyn::Rod::scaleDrag ( real scaler )

inline

Scale the drag coefficients.

Parameters

scaler The drag coefficients scale factor

◆ Serialize()

std::vector< uint64_t > moordyn::Rod::Serialize ( void )

virtual

Produce the packed data to be saved.

The produced data can be used afterwards to restore the saved information afterwards calling Deserialize(void).

Thus, this function is not processing the information that is extracted from the definition file

Returns: The packed data

Implements moordyn::io::IO.

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◆ setDependentStates()

void moordyn::Rod::setDependentStates ( )

Set the end kinematics then set the states (positions and velocities) of any line ends attached to this rod.

This also determines the orientation of zero-length rods.

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◆ setDrag()

void moordyn::Rod::setDrag	(	real	cdn,
		real	cdt
	)

inline

Set the drag coefficients.

Parameters

cdn	Normal (transversal) coefficient
cdt	tangential (axial) coefficient

◆ setKinematics()

void moordyn::Rod::setKinematics	(	vec6	r,
		vec6	rd
	)

Take the kinematics from the fairlead information.

set kinematics for Rods ONLY if they are attached to a body (including a coupled body) (otherwise shouldn't be called)

Parameters

r	Position
rd	Velocity

Exceptions

moordyn::invalid_value_error If the rod is not of type moordyn::Rod::FIXED or moordyn::Rod::PINNED

Note: If the rod is of type moordyn::Rod::PINNED, then just 3 components of r and rd are considered

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◆ setState()

void moordyn::Rod::setState ( const InstanceStateVarView r )

virtual

Set the rod state.

for a free Rod, there are 12 states: [x, y, z velocity of end A, then rate of change of u/v/w coordinates of unit vector pointing toward end B, then x, y, z coordinate of end A, u/v/w coordinates of unit vector pointing toward end B]

for a pinned Rod, there are 6 states (rotational only): [rate of change of u/v/w coordinates of unit vector pointing toward end B, then u/v/w coordinates of unit vector pointing toward end B]

Parameters

r	The rod states

Exceptions

invalid_value_error If the rod is not of type FREE, CPLDPIN or PINNED

Implements moordyn::Instance.

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◆ setTime()

void moordyn::Rod::setTime ( real time )

inline

Set the line simulation time.

Parameters

time	Simulation time

◆ setup()

void moordyn::Rod::setup	(	int	number,
		types	type,
		RodProps *	props,
		vec6	endCoords,
		unsigned int	n,
		EnvCondRef	env_in,
		shared_ptr< ofstream >	outfile,
		string	channels
	)

Setup a rod.

Parameters

number	Rod ID
type	Rod type
props	Rod properties
endCoords	The coordinates of both end points
n	Number of segments
env_in	Global struct that holds environmental settings
outfile	The outfile where information shall be witten
channels	The channels/fields that shall be printed in the file

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◆ setWaves()

void moordyn::Rod::setWaves	(	moordyn::WavesRef	waves_in,
		moordyn::SeafloorRef	seafloor_in
	)

inline

Set the environmental data.

Parameters

waves_in	Global Waves object
seafloor_in	Global Seafloor object

◆ stateDims()

const size_t moordyn::Rod::stateDims ( ) const

inlinevirtual

Get the dimension of the state variable.

Returns: 7 components for position quaternion and 6 components for linear and angular velocities, i.e. 13 components

Warning: This function shall be called after ::setup()

Reimplemented from moordyn::Instance.

◆ stateN()

const size_t moordyn::Rod::stateN ( ) const

inlinevirtual

Get the number of state variables required by this instance.

Returns: 1

Reimplemented from moordyn::Instance.

◆ TypeName()

static string moordyn::Rod::TypeName ( types t )

inlinestatic

Return a string with the name of a type.

This tool is useful mainly for debugging

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◆ updateFairlead()

void moordyn::Rod::updateFairlead ( real time )

Sets the kinematics.

This function is meant only for coupled or fixed bodies

Parameters

time	Local time within the time step (from 0 to dt)

Exceptions

moordyn::invalid_value_error If the rod is not of type moordyn::Rod::COUPLED or moordyn::Rod::CPLDPIN

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

/home/docs/checkouts/readthedocs.org/user_builds/moordyn/checkouts/latest/source/Rod.hpp
/home/docs/checkouts/readthedocs.org/user_builds/moordyn/checkouts/latest/source/Rod.cpp

Public Types

Public Member Functions

Static Public Member Functions

Public Attributes

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

◆ types

Constructor & Destructor Documentation

◆ Rod()

Member Function Documentation

◆ addLine()

◆ Deserialize()

◆ doRHS()

◆ getDrag()

◆ getFnet()

◆ getM()

◆ getN()

◆ getNetForceAndMass() [1/2]

◆ getNetForceAndMass() [2/2]

◆ getNodePos()

◆ getNodeVel()

◆ GetRodOutput()

◆ getState() [1/2]

◆ getState() [2/2]

◆ getStateDeriv()

◆ getUnfreeVel()

◆ getVTK()

◆ initialize() [1/2]

◆ initialize() [2/2]

◆ initiateStep()

◆ removeLine()

◆ saveVTK()

◆ scaleDrag()

◆ Serialize()

◆ setDependentStates()

◆ setDrag()

◆ setKinematics()

◆ setState()

◆ setTime()

◆ setup()

◆ setWaves()

◆ stateDims()

◆ stateN()

◆ TypeName()

◆ updateFairlead()