Class: wsim.powerTakeOff

wsim.powerTakeOff is a base class for the power take-off simulation
classes. It has methods to help with setting up data logging and checking
some standard inputs.

wsim.powerTakeOff Methods:

  powerTakeOff - wsim.powerTakeOff constructor
  start - start the simulation
  advanceStep - advance to the next simulation time step
  finish - end the simulation
  forceAndMoment - calculate the forceAndMoment from the power take-off
   (intended to be reimplemented by child classes).
  logData - appends the internal variable data to the log
  loggingSetup - sets up data logging for a wsim.linearPowerTakeOff object

Inheiritance Graph

digraph graph_for_powerTakeOff { "handle" -> "wsim.powerTakeOff"; }

Parent Class Properties and Methods

handle

Inheirited Properties

None

Inheirited Methods

  • addlistener : ADDLISTENER Add listener for event.
  • addlistener : ADDLISTENER Add listener for event.
  • addlistener : ADDLISTENER Add listener for event.
  • addlistener : ADDLISTENER Add listener for event.
  • addlistener : ADDLISTENER Add listener for event.
  • delete : DELETE Delete a handle object.
  • eq : == (EQ) Test handle equality.
  • findobj : FINDOBJ Find objects matching specified conditions.
  • findprop : FINDPROP Find property of MATLAB handle object.
  • ge : >= (GE) Greater than or equal relation for handles.
  • gt : > (GT) Greater than relation for handles.
  • isvalid : ISVALID Test handle validity.
  • le : <= (LE) Less than or equal relation for handles.
  • listener : LISTENER Add listener for event without binding the listener to the source object.
  • listener : LISTENER Add listener for event without binding the listener to the source object.
  • listener : LISTENER Add listener for event without binding the listener to the source object.
  • listener : LISTENER Add listener for event without binding the listener to the source object.
  • listener : LISTENER Add listener for event without binding the listener to the source object.
  • lt : < (LT) Less than relation for handles.
  • ne : ~= (NE) Not equal relation for handles.
  • notify : NOTIFY Notify listeners of event.
  • notify : NOTIFY Notify listeners of event.

Properties

  • id
  • loggingInfo
  • loggingOn
  • otherNode
  • referenceNode
  • uniqueLoggingNames

id

positive scalar integer for uniquely idenifying the object

loggingInfo

structure containing information on the variables which will be logged by the PTO

loggingOn

flag indicating whether logging is active for the PTO

otherNode

the other (non-reference node)

referenceNode

the reference node of the PTO, forces motion is relative to this node

uniqueLoggingNames

the logged variable names with a unique prefix for the object

Methods

  • powerTakeOff
  • advanceStep
  • finish
  • forceAndMoment
  • logData
  • loggingSetup
  • start

powerTakeOff

Summary

wsim.powerTakeOff constructor

Syntax

pto = wsim.powerTakeOff (reference_node, other_node, logginginfo)
pto = wsim.powerTakeOff (..., 'Parameter', value)

Description

wsim.powerTakeOff is a base class for the power take-off
simulation classes. It has methods to help with setting up
data logging and checking some standard inputs.

Inputs

reference_node

mbdyn.pre.structuralNode object

other_node

mbdyn.pre.structuralNode object

logginginfo

scalar structure containing the following
fields:

AvailableNames : cell array of variable names that can be
 logged. To use the logData method of the powerTakeOff
 class, each name must correspond to a field of a structure
 in the class property, internalVariables. When calling
 logData, it is the contents of the this variable which is
 appended to the log.

 From the AvailableNames, a unique variable name is created
 for use in the logger object based on the pto id. Data is
 actually logged to this unique name in the logger. This
 ensures data for mutiple PTO objects of the same type can
 be logged in the same logger object. The unique logging
 names are stored in the uniqueLoggingNames property of the
 class. The variables which are actually logged can be
 restricted by using the LoggedVars option (see below)

IndepVars : cell array the same size as the AvailableNames
 field containing the name of the independant variable
 associated with the corresponding variable name in
 AvailableNames, e.g. 'Time'. If there is no independant
 variable, the cell should contain an empty character
 vector (or just be empty).

Sizes : cell array containing vector containing the size of
 each of the the logged variables.

Descriptions : cell array of character vectors containing
 descriptions of the variables. Each cell can be empty, but
 the cell array must be of the same length as the
 AvailableNames cell array.

AxisLabels : cell array of character vectors, each
 containing the label to use when plotting the variable, on
 the axis for that variable, e.g. 'Force [N]', or
 'Displacement [m]'.

Additional arguments may be supplied as parameter-value pairs:

LoggedVars

cell array of character vectors containing
the names of internal variables to be logged. If supplied,
only those variables named in this cell array will
actually have data logged. Alternatively, this can be a
character vector, 'none', in which case no internal
variables will be logged. Default is an empty cell array,
which means all available internal variables will be
logged.

Outputs

pto

wsim.powerTakeOff object

See Also

advanceStep

Summary

advance to the next simulation time step

Syntax

advanceStep (pto)

Description

wsim.powerTakeOff.advanceStep is intended to be called when
the simulation is ready to advance to the next time step. It
is always called when the powerTakeOff is used with the
wsim.wecSim class to manage a simulation. The only tasks done
by wsim.powerTakeOff.advanceStep is to log data to the
wsim.logger object (internally it calls
wsim.powerTakeOff.logData). It is intended that subclasses of
wsim.powerTakeOff can extend this method to perform other
tasks.

Inputs

pto

wsim.powerTakeOff object

See Also

finish

Summary

method called at end of wecSim simulation

Syntax

finish (pto)

Description

finish will be called by the wsim.wecSim class at the end of
a simulation. It is intended to be reimplemented by child
classes which need to perform tasks (e.g. closing
communications, destroying emeory etc.) after the main
simulation has completed. The implemetation here in
wsim.powerTakeOff does nothing.

Inputs

pto

wsim.powerTakeOff object

forceAndMoment

Summary

forceAndMoment should return the force and moment from a PTO

Syntax

forceAndMoment (pto)

Description

forceAndMoment is intended to be reimplemented by child
classes and should return the forces and moments from the PTO
on the two attached nodes as a (6 x 2) matrix. The
implemetation here in wsim.powerTakeOff does nothing.

Inputs

pto

wsim.powerTakeOff object

logData

Summary

appends the internal variable data to the log

Syntax

logData (pto)

Description

logData appends the last recorded values of the internal
variables to a logger object.

Inputs

pto

wsim.powerTakeOff object

See Also

wsim.powerTakeOff.advanceStep

loggingSetup

Summary

sets up data logging for a wsim.linearPowerTakeOff object

Syntax

info = loggingSetup (lpto)
info = loggingSetup (lpto, logger)

Description

loggingSetup initialises

Inputs

lpto

wsim.powerTakeOff object

logger

optional wsim.logger object

Outputs

info

structure containing information on the data to be
logged by the PTO. Will contain the following fields:
AvailableNames, IndepVars, Sizes, Descriptions, and
NAvailable.

See Also

wsim.powerTakeOff.advanceStep

start

Summary

initialise the pto simulation

Syntax

start (pto, siminfo)

Description

wsim.powerTakeOff.start is called by wecSim at the beginning
of a simulation to allow any initialisation to take place.

Inputs

pto

wsim.powerTakeOff object

siminfo

structure containing information about the
simulation the PTO is part of. It should contain the
following fields:

TStart : Start time of the simulation

TEnd : End time of the simulation

TStep : Time step size

MBDynSystem : the MBDyn object used in the simulation

HydroSystem : the wsim.hydroSystem object used in the
 simulation

See Also