artisynth.core.femmodels

Class FrameFem3dConstraint

java.lang.Object

artisynth.core.modelbase.ModelComponentBase

artisynth.core.mechmodels.ConstrainerBase

artisynth.core.femmodels.FrameFem3dConstraint

All Implemented Interfaces:

Constrainer, HasNumericState, ModelComponent, PostScannable, java.lang.Cloneable, HasProperties, HierarchyNode, Scannable

public class FrameFem3dConstraint
extends ConstrainerBase

Class to manage the constraint between an FEM and it's coordinate frame.

Nested Class Summary

Nested classes/interfaces inherited from interface artisynth.core.modelbase.ModelComponent

ModelComponent.NavpanelVisibility

Field Summary

Fields inherited from class artisynth.core.modelbase.ModelComponentBase

enforceUniqueCompositeNames, enforceUniqueNames, myNumber, myProps, NULL_OBJ, useCompactPathNames

Constructor Summary

Constructors

Constructor and Description
FrameFem3dConstraint()
FrameFem3dConstraint(Frame frame, FemElement3dBase elem)

Method Summary

Modifier and Type	Method and Description
int	addBilateralConstraints(SparseBlockMatrix GT, VectorNd dg, int numb) Appends the current bilateral force constraint matrix Gc^T to the matrix GT, by appending block columns to it.
void	computeFrame(RigidTransform3d T)
void	computeFrameRelativeVelocity(Twist vel) Computes the current frame velocity, in frame coordinates.
void	computeVelocity(Twist vel) Computes the current frame velocity, in world coordinates.
int	getBilateralForces(VectorNd lam, int idx) Returns the bilateral forces that were most recently set for this constrainer using Constrainer.setBilateralForces(maspack.matrix.VectorNd, double, int).
int	getBilateralInfo(MechSystem.ConstraintInfo[] ginfo, int idx) Returns constraint information for each row of the bilateral constraint system
void	getBilateralSizes(VectorNi sizes) Returns the sizes of each block column in the bilateral force constraint matrix.
void	getConstrainedComponents(java.util.List<DynamicComponent> list) Collected all the dynamic components constrained by this constrainer.
FemElement3dBase	getElement()
int	setBilateralForces(VectorNd lam, double s, int idx) Sets the bilateral forces that were computed to enforce this constraint.
void	setFromElement(RigidTransform3d T, FemElement3dBase elem)
double	updateConstraints(double t, int flags) Updates the current set of constraints, and returns the maximum penetration > 0 associated with all of them.
void	updateFramePose(boolean frameRelative)
void	zeroForces() Zeros all bilateral and unilateral constraint forces in this constraint.

Methods inherited from class artisynth.core.mechmodels.ConstrainerBase

addFrictionConstraints, addUnilateralConstraints, getFrictionForces, getFrictionState, getState, getUnilateralForces, getUnilateralInfo, getUnilateralSizes, getUnilateralState, hasState, maxFrictionConstraintSets, setFrictionForces, setFrictionState, setState, setUnilateralForces, setUnilateralState

Methods inherited from class artisynth.core.modelbase.ModelComponentBase

checkFlag, checkName, checkNameUniqueness, clearFlag, clone, connectToHierarchy, copy, createTempFlag, disconnectFromHierarchy, getAllPropertyInfo, getChildren, getGrandParent, getHardReferences, getName, getNameRange, getNavpanelVisibility, getNavpanelVisibility, getNumber, getParent, getProperty, getSoftReferences, hasChildren, isFixed, isMarked, isScanning, isSelected, isWritable, makeValidName, makeValidName, notifyParentOfChange, postscan, printReferences, recursivelyContained, recursivelyContains, removeTempFlag, scan, setFixed, setFlag, setMarked, setName, setNavpanelVisibility, setNavpanelVisibility, setNumber, setParent, setScanning, setSelected, setWritable, updateReferences, write

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface artisynth.core.modelbase.HasNumericState

advanceState, getAuxVarDerivative, getAuxVarState, getStateVersion, numAuxVars, requiresAdvance, setAuxVarState

Constructor Detail

FrameFem3dConstraint

public FrameFem3dConstraint()

FrameFem3dConstraint

public FrameFem3dConstraint(Frame frame,
                            FemElement3dBase elem)

Method Detail

getBilateralSizes

public void getBilateralSizes(VectorNi sizes)

Description copied from interface: Constrainer

Returns the sizes of each block column in the bilateral force constraint matrix. The size for each block should be appended to the vector sizes.

Specified by:

getBilateralSizes in interface Constrainer

Specified by:

getBilateralSizes in class ConstrainerBase

Parameters:

sizes - vector to which the block column sizes are appended

addBilateralConstraints

public int addBilateralConstraints(SparseBlockMatrix GT,
                                   VectorNd dg,
                                   int numb)

Description copied from interface: Constrainer

Appends the current bilateral force constraint matrix Gc^T to the matrix GT, by appending block columns to it. If the argument dg is non-null, it should be used to return the velocity constraint time derivative, defined by

 \dot Gc vel
 

starting at the location numb. In all cases, the method must return an updated value of numb, incremented by the total row size of Gc.

Specified by:

addBilateralConstraints in interface Constrainer

Specified by:

addBilateralConstraints in class ConstrainerBase

Parameters:

GT - matrix to which the bilateral force contraint matrix is appended.

dg - if non-null, returns the velocity constraint time derivative

numb - starting index for time derivative in dg

Returns:

updated value of numb

getBilateralInfo

public int getBilateralInfo(MechSystem.ConstraintInfo[] ginfo,
                            int idx)

Description copied from interface: Constrainer

Returns constraint information for each row of the bilateral constraint system

 Gc vel = 0.
 

This information is placed in pre-allocated MechSystem.ConstraintInfo structures in ginfo, starting at idx. The method must return an updated value of idx, incremented by the number of rows of Gc.

The constraint information to be set in ConstraintInfo includes:

   dist        // distance to the constraint surface.
   compliance  // if > 0, gives constraint compliance value
   damping     // damping; only used if compliance > 0
   force       // used for computing non-linear compliance
 

Specified by:

getBilateralInfo in interface Constrainer

Specified by:

getBilateralInfo in class ConstrainerBase

Parameters:

ginfo - returns the constraint information

idx - starting location in ginfo for returning constraint info

Returns:

updated value of idx

setBilateralForces

public int setBilateralForces(VectorNd lam,
                              double s,
                              int idx)

Description copied from interface: Constrainer

Sets the bilateral forces that were computed to enforce this constraint. These are the Lagrange multipliers for the columns of the transposed bilateral constraint matrix. The forces are supplied in lam, starting at the index idx, and should be scaled by s. (In practice, s is used to convert from impulses to forces.) The method must return an updated value of idx, incremented by the number of forces associated with this constraint.

Specified by:

setBilateralForces in interface Constrainer

Specified by:

setBilateralForces in class ConstrainerBase

Parameters:

lam - supplies the force impulses, which should be scaled by s

s - scaling factor for the force values

idx - starting index of forces in lam

Returns:

updated value of idx

getBilateralForces

public int getBilateralForces(VectorNd lam,
                              int idx)

Description copied from interface: Constrainer

Returns the bilateral forces that were most recently set for this constrainer using Constrainer.setBilateralForces(maspack.matrix.VectorNd, double, int). The forces are returned in lam, starting at the index idx. The method must return an updated value of idx, incremented by the number of forces associated with this constraint.

Specified by:

getBilateralForces in interface Constrainer

Specified by:

getBilateralForces in class ConstrainerBase

Parameters:

lam - returns the forces

idx - starting index for forces in lam

Returns:

updated value of idx

zeroForces

public void zeroForces()

Description copied from interface: Constrainer

Zeros all bilateral and unilateral constraint forces in this constraint.

Specified by:

zeroForces in interface Constrainer

Specified by:

zeroForces in class ConstrainerBase

updateConstraints

public double updateConstraints(double t,
                                int flags)

Description copied from interface: Constrainer

Updates the current set of constraints, and returns the maximum penetration > 0 associated with all of them. If no constraints are presently active, returns -1.

Specified by:

updateConstraints in interface Constrainer

Specified by:

updateConstraints in class ConstrainerBase

getConstrainedComponents

public void getConstrainedComponents(java.util.List<DynamicComponent> list)

Description copied from interface: Constrainer

Collected all the dynamic components constrained by this constrainer. Not currently used.

Specified by:

getConstrainedComponents in interface Constrainer

Specified by:

getConstrainedComponents in class ConstrainerBase

Parameters:

list - list to which constrained components should be appended

getElement

public FemElement3dBase getElement()

setFromElement

public void setFromElement(RigidTransform3d T,
                           FemElement3dBase elem)

computeFrame

public void computeFrame(RigidTransform3d T)

computeVelocity

public void computeVelocity(Twist vel)

Computes the current frame velocity, in world coordinates.

computeFrameRelativeVelocity

public void computeFrameRelativeVelocity(Twist vel)

Computes the current frame velocity, in frame coordinates.

updateFramePose

public void updateFramePose(boolean frameRelative)