Node class to apply forces and moments to frames. More...

#include <Node.h>

Inheritance diagram for warptwin::Node:

[legend]

Public Member Functions
	Node (const std::string &name, Frame *par=nullptr)
	Basic constructor for the node object.
const Joint &	tJoint ()
	Function to get reference to the frame's translational joint.
const Joint &	rJoint ()
	Function to get reference to the frame's rotational joint.
void	getFMPairAtParentOrigin (clockwerk::CartesianVector< 3 > &force_parentcg__p, clockwerk::CartesianVector< 3 > &moment_parentcg__p)
	Function to resolve applied forces/moments into a force/moment pair in parent body frame origin.
clockwerk::CartesianVector< 3 >	passthroughForce ()
clockwerk::CartesianVector< 3 >	passthroughMoment ()
Public Member Functions inherited from warptwin::Frame
	Frame (const std::string &name, Frame *par=nullptr, bool free=false)
	Constructor for the frame object.
virtual	~Frame ()
std::vector< Frame * >	frameChildren ()
	Return all children of the frame as a vector of frames.
Frame *	getFrameByAddress (const std::string &address)
	Function to get an object from the graph tree by string address.
Joint &	tJoint ()
	Function to get reference to the frame's translational joint.
Joint &	rJoint ()
	Function to get reference to the frame's rotational joint.
int	parent (Frame *new_parent)
	Function to assign the frame's parent via pointer.
int	parent (Frame &new_parent)
Frame *	parent ()
void	setParentRelAcceleration (clockwerk::CartesianVector< 3 > accel)
	Function to set parent relative acceleration of frame.
void	setParentRelAngularAcceleration (clockwerk::CartesianVector< 3 > alpha)
	Function to set parent relative angular acceleration.
clockwerk::CartesianVector< 3 >	parentRelAcceleration ()
	Function to get the acceleration of the frame relative to parent expressed in parent coords.
clockwerk::CartesianVector< 3 >	parentRelAngularAcceleration ()
	Function to get angular acceleration relative to parent in frame coords.
void	rootRelPosition (clockwerk::CartesianVector< 3 > &pos_o_root__root) const
	Returns the position of the frame origin wrt the root origin, in root coordinates.
clockwerk::CartesianVector< 3 >	rootRelPosition () const
void	rootRelVelocity (clockwerk::CartesianVector< 3 > &vel_o_root__root) const
	Returns the velocity of the frame origin wrt the root origin, in root coordinates.
clockwerk::CartesianVector< 3 >	rootRelVelocity () const
void	rootRelAcceleration (clockwerk::CartesianVector< 3 > &acc_o_root__root) const
	Returns the acceleration of the frame origin wrt the root origin, in root coordinates.
clockwerk::CartesianVector< 3 >	rootRelAcceleration () const
void	rootRelQuaternion (clockwerk::Quaternion &quat_f_root) const
	Returns the quaternion representing the frame origin wrt the root frame.
clockwerk::Quaternion	rootRelQuaternion () const
void	rootRelDCM (clockwerk::DCM &dcm_f_root) const
	Returns the clockwerk::DCM of the frame origin wrt the root frame.
clockwerk::DCM	rootRelDCM () const
void	rootRelAngularVelocity (clockwerk::CartesianVector< 3 > &w_f_root__f) const
	Returns the angular velocity of the frame origin wrt the root, expressed in this frame's coordinates.
clockwerk::CartesianVector< 3 >	rootRelAngularVelocity () const
void	rootRelAngularAcceleration (clockwerk::CartesianVector< 3 > &alpha_f_root__f) const
	Returns the angular acceleration of the frame origin wrt the root, expressed in this frame's coordinates.
clockwerk::CartesianVector< 3 >	rootRelAngularAcceleration () const
int	calcFrameTreeExtForcesMoments ()
	Function to recurse through the body and its children to apply external forces and moments to the "correct" body by resolving them to locations where there are degrees of freedom.
int	calcFrameTreeExtAcceleration ()
	Function to recurse through the body and its children to resolve applied external forces and moments into acceleration and angular acceleration.
void	integrator (void *integ_ptr)
	Getter and setter for integrator pointer.
void *	integrator ()
void	setStateFromStateVector (const std::array< floating_point, 13 > &state_f_p__f)
	Function to set frame state based on NUM_INTEGRATED_STATES-element state vector.
void	getStateAsStateVector (std::array< floating_point, 13 > &state_f_p__f)
	Function to return frame state as a NUM_INTEGRATED_STATES-element state vector.
void	getStateVectorDot (std::array< floating_point, 13 > &state_dot)
	Function to get the rate of change in the frame state vector.
int	setRootRelPosition (const clockwerk::CartesianVector< 3 > &pos_f_root__root)
	Function to set the frame's position relative to root.
int	setRootRelVelocity (const clockwerk::CartesianVector< 3 > &vel_f_root__root)
	Function to set the frame's velocity relative to root.
int	setRootRelAttitude (const clockwerk::Quaternion &quat_f_root)
	Function to set the frame's attitude relative to root.
int	setRootRelAngularVelocity (const clockwerk::CartesianVector< 3 > &w_f_root__f)
	Function to set the frame's position relative to root.
Frame *	getFrameRootPointer ()
	Function to get a pointer to this frame's root frame.
void	dump ()
	Dump all information associated with the frame.
Public Member Functions inherited from clockwerk::GraphTreeObject
	GraphTreeObject (const char gt_nme="", GraphTreeObject *storage_array=nullptr, uint32 storage_size=0)
	Name-based constructor for GraphTreeObject which will have no children by default.
virtual	~GraphTreeObject ()
	Destructor.
GraphTreeObject *	parent ()
	Functions to get object's parent/children.
GraphTreeObject **	children ()
GraphTreeObject *	childAtIndex (uint8 i) const
int16	parent (GraphTreeObject *new_parent)
	Function to assign the node's parent via pointer.
int16	parent (GraphTreeObject &new_parent)
	Function to assign the node's parent via reference.
uint8	nChildren () const
	Getters for number of children and descendants.
uint16	nDescendants () const
uint8	capacity () const
const char *	name () const
	Getter and setter for object name.
int16	name (const char *new_name)
uint8	rank ()
	Getter for the object rank.
int8	type ()
	Function to indicate type – -1 by default unless implemented downstream.
bool	loggable ()
	Getter for object logability flag – note no setter because should only be set by this or a derived class in its definition.
GraphTreeObject *	getRootDataPointer ()
	Get the pointer to the highest object in the graph tree.
virtual int16	str (char *output, size_t size) const
	Get object represented as string.
virtual int16	fromStr (const char *val)
	Set value of graphtreeobject from string.

Public Attributes
clockwerk::DataIO< clockwerk::CartesianVector< 3 > >	force = clockwerk::DataIO<clockwerk::CartesianVector<3>>(nullptr, "force", clockwerk::CartesianVector<3>({0.0,0.0,0.0}))
	The force applied at the node.
clockwerk::DataIO< Frame * >	force_frame = clockwerk::DataIO<Frame*>(nullptr, "force_frame", nullptr)
	The frame in which the force is applied. Using this utility abstracts away framerotate commands and also allows forces to be applied inertially or frame locally, because rotation will occur every step.
clockwerk::DataIO< clockwerk::CartesianVector< 3 > >	moment
	The moment applied at the node.
clockwerk::DataIO< Frame * >	moment_frame = clockwerk::DataIO<Frame*>(nullptr, "moment_frame", nullptr)
	The frame in which the moment is applied Using this utility abstracts away framerotate commands and also allows moments to be applied inertially or frame locally, because rotation will occur every step.
clockwerk::DataIO< Node * >	self_id = clockwerk::DataIO<Node*>(nullptr, "self_id", this)
Public Attributes inherited from warptwin::Frame
clockwerk::DataIO< clockwerk::CartesianVector< 3 > >	pos_f_p__p
clockwerk::DataIO< clockwerk::CartesianVector< 3 > >	vel_f_p__p
clockwerk::DataIO< clockwerk::Quaternion >	quat_f_p
clockwerk::DataIO< clockwerk::CartesianVector< 3 > >	ang_vel_f_p__f
clockwerk::DataIO< Frame * >	self_id = clockwerk::DataIO<Frame*>(nullptr, "self_id", this)

Protected Attributes
clockwerk::CartesianVector< 3 >	_passthrough_force__b
clockwerk::CartesianVector< 3 >	_passthrough_moment__b
Protected Attributes inherited from warptwin::Frame
clockwerk::CartesianVector< 3 >	_acc_f_p__p
clockwerk::CartesianVector< 3 >	_alpha_f_p__f
Joint	_t_joint
Joint	_r_joint
	Translational.
void *	_integrator_ptr = nullptr
	Rotational.
Frame *	_parent
	Variable to hold our parent.
Protected Attributes inherited from clockwerk::GraphTreeObject
GraphTreeObject *	_parent = nullptr
GraphTreeObject **	_children_ptr = nullptr
uint32	_max_num_children = 0
uint16	_num_descendants = 0
char	_name [MAXIMUM_NAME_CHARS] = ""
	String name for object.
uint8	_num_children = 0
	Number of direct children of the tree (not including the tree itself).
uint8	_rank = 0
int8	_graph_tree_type = BASE_GRAPH_TREE
	Variable to store graph tree object type.
bool	_loggable = false
	Variable to indicate whether the selected object is loggable. Set to false by default.
uint32	_index = 0
	Index pointing to the next write location for the graph tree children.

Additional Inherited Members
Protected Member Functions inherited from clockwerk::GraphTreeObject
int16	_setStorage (GraphTreeObject **storage_array, uint8 storage_size)
	Getter for object's string address.
void	_recalculateDescendants ()
	Function to recursively re-calculate the number of descendants of a given node on the tree.
void	_recalculateRank ()
	Function to recursively re-calculate the rank of a given node on the tree.
int16	_addChild (GraphTreeObject *child)
	Function to decompose a string into a series of substrings via indexing.
int16	_removeChild (GraphTreeObject *child)
	Function to remove a child from the graph node's children.

Detailed Description

Node class to apply forces and moments to frames.

This file defines the base node class which is used to apply forces and sense accelerations at fixed locations on bodies.

The node class is a special Frame that is fully fixed to its parent (i.e. cannot be fully free) and has special handles for applying forces and moments. Because it is a simple fixed frame, it is also ideal for sensing accelerations and states, in applications such as an accelerometer.

Applying forces in the node frame is done via the force() and moment() DataIO objects. By default, forces and moments are applied in the node frame. However, passing a frame argument to the force_frame or moment_frame objects causes forces and moments to be applied in that frame – this is particularly useful for cases where the node frame is rotating but the force is not, such as gravity applied to a rotating spacecraft node.

Constructor & Destructor Documentation

◆ Node()

warptwin::Node::Node	(	const std::string &	name,
		Frame *	par = nullptr )

Basic constructor for the node object.

Parameters

name	The name of the node
par	The node's parent. Nullptr by default

Member Function Documentation

◆ getFMPairAtParentOrigin()

void warptwin::Node::getFMPairAtParentOrigin	(	clockwerk::CartesianVector< 3 > &	force_parentcg__p,
		clockwerk::CartesianVector< 3 > &	moment_parentcg__p )

Function to resolve applied forces/moments into a force/moment pair in parent body frame origin.

Parameters

force_parentcg__p	Implicit return of force applied to this node in the parent body frame
moment_parentcg__p	Implicit return of moment applied to this node in the parent body frame, RESOLVED TO A FORCE/MOMENT COUPLE AT THE PARENT FRAME LOCATION

◆ passthroughForce()

clockwerk::CartesianVector< 3 > warptwin::Node::passthroughForce ( )

inline

◆ passthroughMoment()

clockwerk::CartesianVector< 3 > warptwin::Node::passthroughMoment ( )

inline

◆ rJoint()

const Joint & warptwin::Node::rJoint ( )

inline

Function to get reference to the frame's rotational joint.

Returns: The frame's rotational joint

Note: OVERRIDES frame default joint with unmodifiable version

◆ tJoint()

const Joint & warptwin::Node::tJoint ( )

inline

Function to get reference to the frame's translational joint.

Returns: The frame's translational joint

Note: OVERRIDES frame default joint with unmodifiable version

Member Data Documentation

◆ _passthrough_force__b

clockwerk::CartesianVector<3> warptwin::Node::_passthrough_force__b

protected

Passthrough force on the node – force not applied here but passed on to parent body All forces and moments should be passed through for nodes

◆ _passthrough_moment__b

clockwerk::CartesianVector<3> warptwin::Node::_passthrough_moment__b

protected

◆ force

clockwerk::DataIO<clockwerk::CartesianVector<3> > warptwin::Node::force = clockwerk::DataIO<clockwerk::CartesianVector<3>>(nullptr, "force", clockwerk::CartesianVector<3>({0.0,0.0,0.0}))

The force applied at the node.

◆ force_frame

clockwerk::DataIO<Frame*> warptwin::Node::force_frame = clockwerk::DataIO<Frame*>(nullptr, "force_frame", nullptr)

The frame in which the force is applied. Using this utility abstracts away framerotate commands and also allows forces to be applied inertially or frame locally, because rotation will occur every step.

Note: Our node only rotates from the force frame – no translation or coupling

◆ moment

clockwerk::DataIO<clockwerk::CartesianVector<3> > warptwin::Node::moment

Initial value:

= clockwerk::DataIO<clockwerk::CartesianVector<3>>(nullptr,

"moment", clockwerk::CartesianVector<3>({0.0,0.0,0.0}))

clockwerk::CartesianVector

Standard vector class derived from Matrix.

Definition CartesianVector.hpp:39

clockwerk::DataIO

Class for inter-object communication.

Definition DataIO.hpp:60

The moment applied at the node.

◆ moment_frame

clockwerk::DataIO<Frame*> warptwin::Node::moment_frame = clockwerk::DataIO<Frame*>(nullptr, "moment_frame", nullptr)

The frame in which the moment is applied Using this utility abstracts away framerotate commands and also allows moments to be applied inertially or frame locally, because rotation will occur every step.

Note: Our node only rotates from the moment frame – no translation or coupling

◆ self_id

clockwerk::DataIO<Node*> warptwin::Node::self_id = clockwerk::DataIO<Node*>(nullptr, "self_id", this)

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

/Users/mickey/Documents/Projects/warptwin/cpp/src/frames/Node.h
/Users/mickey/Documents/Projects/warptwin/cpp/src/frames/Node.cpp

Public Member Functions

Public Attributes

Protected Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ Node()

Member Function Documentation

◆ getFMPairAtParentOrigin()

◆ passthroughForce()

◆ passthroughMoment()

◆ rJoint()

◆ tJoint()

Member Data Documentation

◆ _passthrough_force__b

◆ _passthrough_moment__b

◆ force

◆ force_frame

◆ moment

◆ moment_frame

◆ self_id