artisynth.core.mechmodels

Class JointCoordinateCoupling

java.lang.Object

artisynth.core.modelbase.ModelComponentBase

artisynth.core.mechmodels.ConstrainerBase

artisynth.core.mechmodels.JointCoordinateCoupling

All Implemented Interfaces:

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

public class JointCoordinateCoupling
extends ConstrainerBase
implements BodyConstrainer

Nested Class Summary

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

ModelComponent.FilePathSaveType, 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
JointCoordinateCoupling()
JointCoordinateCoupling(java.util.List<JointCoordinateHandle> coords, Diff1FunctionNx1 fxn)
JointCoordinateCoupling(java.lang.String name, java.util.List<JointCoordinateHandle> coords, Diff1FunctionNx1 fxn)

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.
int	addBilateralConstraints(SparseBlockMatrix GT, VectorNd dg, int numb, int[] solveIndexMap) Implementation of Constrainer.addBilateralConstraints(SparseBlockMatrix,VectorNd,int) that allows the block row positions in GT to be reassigned vis a solve matrix map.
int	addUnilateralConstraints(SparseBlockMatrix NT, VectorNd dn, int numu, int[] solveIndexMap) Implementation of Constrainer.addUnilateralConstraints(SparseBlockMatrix,VectorNd,int) that allows the block row positions in NT to be reassigned vis a solve matrix map.
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.HashSet<DynamicComponent> comps) Collected all the dynamic components constrained by this constrainer.
java.util.ArrayList<JointCoordinateHandle>	getCoordinateHandles() Returns the coordinate handles used by this coupling.
double	getScaleFactor()
int	setBilateralForces(VectorNd lam, double s, int idx) Sets the bilateral forces that were computed to enforce this constraint.
void	setScaleFactor(double s)
double	updateConstraints(double t, int flags) Updates the current set of constraints, and returns the maximum penetration > 0 associated with all of them.
void	updateCoordinateValue() Explicitly update the coordinate value associated with this coupling, based on the current value of the independent coordinates.
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.mechmodels.Constrainer

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

Methods inherited from interface artisynth.core.modelbase.HasNumericState

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

Constructor Detail

JointCoordinateCoupling

public JointCoordinateCoupling()

JointCoordinateCoupling

public JointCoordinateCoupling(java.util.List<JointCoordinateHandle> coords,
                               Diff1FunctionNx1 fxn)

JointCoordinateCoupling

public JointCoordinateCoupling(java.lang.String name,
                               java.util.List<JointCoordinateHandle> coords,
                               Diff1FunctionNx1 fxn)

Method Detail

getScaleFactor

public double getScaleFactor()

setScaleFactor

public void setScaleFactor(double s)

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

updateCoordinateValue

public void updateCoordinateValue()

Explicitly update the coordinate value associated with this coupling, based on the current value of the independent coordinates.

getCoordinateHandles

public java.util.ArrayList<JointCoordinateHandle> getCoordinateHandles()

Returns the coordinate handles used by this coupling. These should not be modified.

addBilateralConstraints

public 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. 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

addBilateralConstraints

public int addBilateralConstraints(SparseBlockMatrix GT,
                                   VectorNd dg,
                                   int numb,
                                   int[] solveIndexMap)

Implementation of Constrainer.addBilateralConstraints(SparseBlockMatrix,VectorNd,int) that allows the block row positions in GT to be reassigned vis a solve matrix map. This enables the creation of constrained system equations for model component subsets.

Specified by:

addBilateralConstraints in interface BodyConstrainer

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

solveIndexMap - if non-null, maps the solve indices of the constrained components onto the block-row indices of GT.

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

addUnilateralConstraints

public int addUnilateralConstraints(SparseBlockMatrix NT,
                                    VectorNd dn,
                                    int numu,
                                    int[] solveIndexMap)

Implementation of Constrainer.addUnilateralConstraints(SparseBlockMatrix,VectorNd,int) that allows the block row positions in NT to be reassigned vis a solve matrix map. This enables the creation of constrained system equations for model component subsets.

Specified by:

addUnilateralConstraints in interface BodyConstrainer

Parameters:

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

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

numu - starting index for time derivative in dg

solveIndexMap - if non-null, maps the solve indices of the constrained components onto the block-row indices of NT.

Returns:

updated value of numb

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.HashSet<DynamicComponent> comps)

Description copied from interface: Constrainer

Collected all the dynamic components constrained by this constrainer.

Specified by:

getConstrainedComponents in interface Constrainer

Specified by:

getConstrainedComponents in class ConstrainerBase

Parameters:

comps - set to which constrained components should be added