artisynth.core.mechmodels

Class JointBase

java.lang.Object

artisynth.core.modelbase.ModelComponentBase

artisynth.core.mechmodels.ConstrainerBase

artisynth.core.mechmodels.RenderableConstrainerBase

artisynth.core.mechmodels.BodyConnector

artisynth.core.mechmodels.JointBase

All Implemented Interfaces:

BodyConstrainer, Constrainer, HasCoordinateFrame, HasNumericState, ModelComponent, PostScannable, RenderableComponent, TransformableGeometry, ScalableUnits, java.lang.Cloneable, HasProperties, HierarchyNode, HasRenderProps, IsRenderable, IsSelectable, Renderable, Scannable

Direct Known Subclasses:

CustomJoint, CylindricalJoint, EllipsoidJoint, EllipsoidJoint3d, FixedAxisJoint, FreeJoint, HingeJoint, OpenSimCustomJoint, PlanarJoint, PlanarTranslationJoint, SliderJoint, SlottedHingeJoint, SolidJoint, SphericalJointBase, UniversalJoint

public abstract class JointBase
extends BodyConnector

Subclass of BodyConnector that provides support for coordinates.

Nested Class Summary

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

ModelComponent.FilePathSaveType, ModelComponent.NavpanelVisibility

Field Summary

Fields

Modifier and Type	Field and Description
static double	DEFAULT_SHAFT_LENGTH
static double	DEFAULT_SHAFT_RADIUS
static PropertyList	myProps

Fields inherited from class artisynth.core.mechmodels.BodyConnector

debug, useOldDerivativeMethod

Fields inherited from class artisynth.core.modelbase.ModelComponentBase

enforceUniqueCompositeNames, enforceUniqueNames, myNumber, NULL_OBJ, useCompactPathNames

Fields inherited from interface artisynth.core.modelbase.TransformableGeometry

TG_ARTICULATED, TG_DRAGGER, TG_PRESERVE_ORIENTATION, TG_SIMULATING

Fields inherited from interface maspack.render.IsRenderable

TRANSPARENT, TWO_DIMENSIONAL

Constructor Summary

Constructors

Constructor and Description
JointBase()

Method Summary

Modifier and Type	Method and Description
int	addCoordinateMobilities(SparseBlockMatrix M, int colSize, int[] solveIndexMap) Adds columns to the matrix M corresponding to the mobilities of the coordinates of this joint.
void	addCoordinateSolveBlocks(SparseNumberedBlockMatrix M, int idx)
void	addCoordinateVelJacobian(SparseNumberedBlockMatrix M, int idx, double s)
void	applyCoordinateForce(int idx, double f) Applies a generalized force to the idx-th coordinate for this joint.
void	coordinatesToTCD(RigidTransform3d TCD, VectorNd coords) Computes the TCD transform for a set of coordinates, if coordinates are supported.
PropertyInfoList	getAllPropertyInfo() Returns a list giving static information about all properties exported by this object.
double	getCoordinate(int idx) Returns the idx-th coordinate value for this joint.
double	getCoordinateDeg(int idx) Returns the idx-th coordinate value for this joint.
int	getCoordinateIndex(java.lang.String name) Returns the index for the coordinate with a given name.
RigidBodyConstraint.MotionType	getCoordinateMotionType(int idx) Returns the motion type of the idx-th coordinate for this joint.
java.lang.String	getCoordinateName(int idx) Returns the name for the idx-th coordinate for this joint.
DoubleInterval	getCoordinateRange(int idx) Queries the range for the idx-th coordinate.
DoubleInterval	getCoordinateRangeDeg(int idx) Queries the range for the idx-th coordinate.
void	getCoordinates(VectorNd coords) Returns the current coordinates, if any, for this joint.
double	getCoordinateSpeed(int idx) Returns the current speed of the idx-th coordinate for this joint.
double	getCoordinateValue(int idx) Returns the current stored value of the idx-th coordinate for this joint.
double	getCoordinateValueDeg(int idx) Returns the current stored value of the idx-th coordinate for this joint.
double	getMaxCoordinate(int idx) Queries the maximum range value for the idx-th coordinate.
double	getMaxCoordinateDeg(int idx) Queries the maximum range value for the idx-th coordinate.
double	getMinCoordinate(int idx) Queries the minimum range value for the idx-th coordinate.
double	getMinCoordinateDeg(int idx) Queries the minimum range value for the idx-th coordinate.
void	getPosition(Point3d pos)
double	getRangeLimitCompliance(int idx) Returns the compliance for the unilateral constraint used to enforce the range limits of coordinate idx.
double	getRangeLimitDamping(int idx) Returns the damping for the unilateral constraint used to enforce the range limits of coordinate idx.
double	getRangeLimitForce(int idx) Returns the current force, if any, being used to enforce the range limits of coordinate idx.
double	getShaftLength() Returns a length used for rendering shafts or axes associated with this joint.
double	getShaftRadius() Returns a radius used for rendering shafts or axes associated this joint.
void	getStoredCoordinates(VectorNd coords) Returns the coordinate values currently stored for this joint.
RigidTransform3d	getStoredTCD()
void	getStoredTCD(RigidTransform3d TCD) Returns the value of the TCD transform based on the coordinate values currently stored for this joint.
boolean	isCoordinateLocked(int idx) Queries whether the idx-th coordinate for this joint is locked.
int	numCoordinates() Returns the number of coordinates, if any, associated with this joint.
void	setCoordinate(int idx, double value) Sets the idx-th coordinate for this joint.
void	setCoordinateDeg(int idx, double value) Sets the idx-th coordinate for this joint.
void	setCoordinateLocked(int idx, boolean locked) Sets whether the idx-th coordinate for this joint is locked, meaning that it will hold its current value.
void	setCoordinateName(int idx, java.lang.String name) Sets the name for the idx-th coordinate supported by this coupling.
void	setCoordinateRange(int idx, DoubleInterval range) Sets the range for the idx-th coordinate.
void	setCoordinateRangeDeg(int idx, DoubleInterval range) Sets the range for the idx-th coordinate.
void	setCoordinates(VectorNd coords) Sets the current coordinates, if any, for this joint.
void	setRangeLimitCompliance(int idx, double c, double d) Sets the compliance and damping (c and d) for the unilateral constraint used to enforce the range limits of coordinate idx.
void	setShaftLength(double l) Sets a length used for rendering shafts or axes associated with this joint.
void	setShaftRadius(double r) Sets a radius used for rendering shafts or axes associated with this joint.

Methods inherited from class artisynth.core.mechmodels.BodyConnector

addBilateralConstraints, addBilateralConstraints, addFrictionConstraints, addMasterBlocks, addTransformableDependencies, addUnilateralConstraints, addUnilateralConstraints, computeConstraintMatrixA, computeConstraintMatrixB, connectToHierarchy, copy, disconnectFromHierarchy, findAttachedBodies, findConnectedBodies, getActivation, getAxisLength, getBilateralForceInA, getBilateralForceInA, getBilateralForceInB, getBilateralForceInB, getBilateralForceInC, getBilateralForceInC, getBilateralForces, getBilateralInfo, getBilateralSizes, getBodyA, getBodyB, getCompliance, getConstrainedComponents, getConstraint, getConstraintFlags, getConstraintForce, getCopyReferences, getCoupling, getCurrentTCD, getCurrentTCW, getCurrentTCW, getCurrentTDW, getCurrentTDW, getDamping, getDrawFrameC, getDrawFrameD, getFrameAttachmentA, getFrameAttachmentB, getFrictionForces, getFrictionState, getHardReferences, getLinearCompliance, getOtherBody, getPenetrationTol, getPenetrationTolMode, getPose, getRenderFrame, getRotaryCompliance, getRotaryLimitTol, getRotaryLimitTolMode, getState, getStateVersion, getTransformDGeometryOnly, getTransformPositionOnly, getUnilateralForceInA, getUnilateralForceInA, getUnilateralForceInB, getUnilateralForceInB, getUnilateralForceInC, getUnilateralForceInC, getUnilateralForces, getUnilateralInfo, getUnilateralSizes, getUnilateralState, hasState, isActive, isConnectedToBodies, isDuplicatable, isEnabled, isNotAttached, maxFrictionConstraintSets, numBilateralConstraints, numConstraints, numEngagedUnilateralConstraints, numUnilateralConstraints, prerender, printConnectedBodies, printConstraintInfo, render, scaleDistance, scaleMass, setAlwaysAdjustBodyA, setAxisLength, setBilateralForces, setBodies, setBodies, setBodies, setBodies, setBodyA, setBodyA, setBodyB, setBodyB, setCompliance, setCurrentTCW, setCurrentTDW, setDamping, setDrawFrameC, setDrawFrameD, setEnabled, setFrictionForces, setFrictionState, setLinearCompliance, setPenetrationTol, setPenetrationTolMode, setRotaryCompliance, setRotaryLimitTol, setRotaryLimitTolMode, setState, setTransformDGeometryOnly, setTransformPositionOnly, setUnilateralForces, setUnilateralState, transformGeometry, transformGeometry, updateAttachments, updateBounds, updateConstraints, withinLoop, zeroForces

Methods inherited from class artisynth.core.mechmodels.RenderableConstrainerBase

createRenderProps, defaultRenderPropsAreNull, getRenderHints, getRenderProps, getSelection, isSelectable, numSelectionQueriesNeeded, setRenderProps

Methods inherited from class artisynth.core.modelbase.ModelComponentBase

checkFlag, checkName, checkNameUniqueness, clearFlag, clone, createTempFlag, getChildren, getGrandParent, 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.TransformableGeometry

transformPriority

Methods inherited from interface artisynth.core.modelbase.HasNumericState

advanceState, getAuxVarDerivative, getAuxVarState, numAuxVars, requiresAdvance, setAuxVarState

Methods inherited from interface artisynth.core.modelbase.ModelComponent

getName, getNavpanelVisibility, getNumber, getParent, getSoftReferences, isFixed, isMarked, isSelected, notifyParentOfChange, scan, setFixed, setMarked, setName, setNumber, setParent, setSelected, setWritable, updateReferences

Methods inherited from interface maspack.properties.HasProperties

getProperty

Methods inherited from interface maspack.properties.HierarchyNode

getChildren, hasChildren

Methods inherited from interface artisynth.core.modelbase.PostScannable

postscan

Methods inherited from interface maspack.util.Scannable

isWritable, write

Field Detail

DEFAULT_SHAFT_LENGTH

public static final double DEFAULT_SHAFT_LENGTH

See Also:

Constant Field Values

DEFAULT_SHAFT_RADIUS

public static final double DEFAULT_SHAFT_RADIUS

See Also:

Constant Field Values

myProps

public static PropertyList myProps

Constructor Detail

JointBase

public JointBase()

Method Detail

getAllPropertyInfo

public PropertyInfoList getAllPropertyInfo()

Description copied from interface: HasProperties

Returns a list giving static information about all properties exported by this object.

Specified by:

getAllPropertyInfo in interface HasProperties

Overrides:

getAllPropertyInfo in class BodyConnector

Returns:

static information for all exported properties

getShaftLength

public double getShaftLength()

Returns a length used for rendering shafts or axes associated with this joint. See setShaftLength(double) for details.

Returns:

shaft rendering length

setShaftLength

public void setShaftLength(double l)

Sets a length used for rendering shafts or axes associated with this joint. The default value is 0. Setting a value of -1 will invoke a legacy rendering method, in shafts and axes are rendered as lines, using line rendering properties, with their length specified by the axisLength property.

Parameters:

l - shaft rendering length

getShaftRadius

public double getShaftRadius()

Returns a radius used for rendering shafts or axes associated this joint. See getShaftRadius() for details.

Returns:

shaft rendering radius

setShaftRadius

public void setShaftRadius(double r)

Sets a radius used for rendering shafts or axes associated with this joint. A value of 0 (which is the default value) will cause the joint to use a default radius which is proportional to getShaftLength().

Parameters:

r - shaft rendering radius

getCoordinateRange

public DoubleInterval getCoordinateRange(int idx)

Queries the range for the idx-th coordinate.

Parameters:

idx - coordinate index

Returns:

coordinate range

getMinCoordinate

public double getMinCoordinate(int idx)

Queries the minimum range value for the idx-th coordinate.

Parameters:

idx - coordinate index

Returns:

minimum range

getMaxCoordinate

public double getMaxCoordinate(int idx)

Queries the maximum range value for the idx-th coordinate.

Parameters:

idx - coordinate index

Returns:

maximum range

setCoordinateRange

public void setCoordinateRange(int idx,
                               DoubleInterval range)

Sets the range for the idx-th coordinate. Specifying range as null will set the range to (-inf, inf).

Parameters:

idx - coordinate index

range - new range value

getCoordinateRangeDeg

public DoubleInterval getCoordinateRangeDeg(int idx)

Queries the range for the idx-th coordinate. If the coordinate motion type is RigidBodyConstraint.MotionType.ROTARY, then the range is returned in degrees.

Parameters:

idx - coordinate index

Returns:

coordinate range

getMinCoordinateDeg

public double getMinCoordinateDeg(int idx)

Queries the minimum range value for the idx-th coordinate. If the coordinate motion type is RigidBodyConstraint.MotionType.ROTARY, then the value is returned in degrees.

Parameters:

idx - coordinate index

Returns:

minimum range

getMaxCoordinateDeg

public double getMaxCoordinateDeg(int idx)

Queries the maximum range value for the idx-th coordinate. If the coordinate motion type is RigidBodyConstraint.MotionType.ROTARY, then the value is returned in degrees.

Parameters:

idx - coordinate index

Returns:

maximum range

setCoordinateRangeDeg

public void setCoordinateRangeDeg(int idx,
                                  DoubleInterval range)

Sets the range for the idx-th coordinate. If the coordinate motion type is RigidBodyConstraint.MotionType.ROTARY, then the range is specified in degrees. Specifying range as null will set the range to (-inf, inf).

Parameters:

idx - coordinate index

range - new range value

setRangeLimitCompliance

public void setRangeLimitCompliance(int idx,
                                    double c,
                                    double d)

Sets the compliance and damping (c and d) for the unilateral constraint used to enforce the range limits of coordinate idx. If c <= 0, then compliance and damping are both set to 0. Otherwise, the compliance is set to c and the damping is set to either d (if d >= 0), or |d| times an estimate of the critical damping (if d < 0).

Parameters:

idx - coordinate index

c - compliance value

d - damping value

getRangeLimitCompliance

public double getRangeLimitCompliance(int idx)

Returns the compliance for the unilateral constraint used to enforce the range limits of coordinate idx.

Parameters:

idx - coordinate index

Returns:

range limit compliance for coordinate idx

getRangeLimitDamping

public double getRangeLimitDamping(int idx)

Returns the damping for the unilateral constraint used to enforce the range limits of coordinate idx.

Parameters:

idx - coordinate index

Returns:

range limit damping for coordinate idx

getRangeLimitForce

public double getRangeLimitForce(int idx)

Returns the current force, if any, being used to enforce the range limits of coordinate idx. The force units will be appropriate to that of the coordinate RigidBodyConstraint.MotionType (e.g., translational force units for RigidBodyConstraint.MotionType.LINEAR, moment units for RigidBodyConstraint.MotionType.ROTARY).

Parameters:

idx - coordinate index

Returns:

range limit force for coordinate idx

numCoordinates

public int numCoordinates()

Returns the number of coordinates, if any, associated with this joint. If coordinates are not supported, this method returns 0.

Returns:

number of joint coordinates

getCoordinateDeg

public double getCoordinateDeg(int idx)

Returns the idx-th coordinate value for this joint. If the coordinate motion type is RigidBodyConstraint.MotionType.ROTARY, then the value is returned in degrees.

Parameters:

idx - index of the coordinate

Returns:

coordinate value

getCoordinate

public double getCoordinate(int idx)

Returns the idx-th coordinate value for this joint. If the joint is connected to other bodies, the value is inferred from the current TCD transform. Otherwise, it is obtained from a stored internal value.

Unlike getCoordinateValue(int), this method causes the coordinate value to be recomputed.

Parameters:

idx - index of the coordinate

Returns:

the coordinate value

getCoordinateValueDeg

public double getCoordinateValueDeg(int idx)

Returns the current stored value of the idx-th coordinate for this joint. If the coordinate motion type is RigidBodyConstraint.MotionType.ROTARY, then the value is returned in degrees.

Unlike getCoordinateDeg(int), this method will not cause the coordinate value to be recomputed.

Parameters:

idx - index of the coordinate

Returns:

the coordinate value

getCoordinateValue

public double getCoordinateValue(int idx)

Returns the current stored value of the idx-th coordinate for this joint.

Unlike getCoordinate(int), this method will not cause the coordinate value to be recomputed.

Parameters:

idx - index of the coordinate

Returns:

the coordinate value

getCoordinateSpeed

public double getCoordinateSpeed(int idx)

Returns the current speed of the idx-th coordinate for this joint.

Parameters:

idx - index of the coordinate

Returns:

the coordinate speed

getCoordinateMotionType

public RigidBodyConstraint.MotionType getCoordinateMotionType(int idx)

Returns the motion type of the idx-th coordinate for this joint.

Parameters:

idx - index of the coordinate

Returns:

coordinate motion type

getCoordinateName

public java.lang.String getCoordinateName(int idx)

Returns the name for the idx-th coordinate for this joint. If the coordinate does not have a name, null is returned.

Parameters:

idx - index of the coordinate

Returns:

coordinate name, or null

setCoordinateName

public void setCoordinateName(int idx,
                              java.lang.String name)

Sets the name for the idx-th coordinate supported by this coupling.

This method allows joint coordinates to be renamed so as to be compatible with the names used by equivalent joints in different modeling systems (e.g., OpenSim). If the joint provides special methods with hardwired names to access coordinate values (e.g., HingeJoint.setTheta(double) and HingeJoint.getTheta() in HingeJoint), those methods will be unaffacted and will continue to access the coordinate at the same location.

Parameters:

idx - index of the coordinate

name - new coordinate name

getCoordinateIndex

public int getCoordinateIndex(java.lang.String name)

Returns the index for the coordinate with a given name. If the joint does not contain a coordinate with the specified name, returns -1.

Parameters:

name - name of the coordinate

Returns:

coordinate index, or -1

applyCoordinateForce

public void applyCoordinateForce(int idx,
                                 double f)

Applies a generalized force to the idx-th coordinate for this joint.

Parameters:

idx - index of the coordinate

f - generalized force to apply

addCoordinateMobilities

public int addCoordinateMobilities(SparseBlockMatrix M,
                                   int colSize,
                                   int[] solveIndexMap)

Adds columns to the matrix M corresponding to the mobilities of the coordinates of this joint. The resulting matrix maps coordinate velocities onto velocities of the bodies to which the joint is attached.

The number of mobilities added equals the number of coordinates, and so the column size of M increases by that amount.

Parameters:

M - mobiliy matrix to add to

colSize - current column size of M

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

Returns:

updated column size of M

addCoordinateSolveBlocks

public void addCoordinateSolveBlocks(SparseNumberedBlockMatrix M,
                                     int idx)

addCoordinateVelJacobian

public void addCoordinateVelJacobian(SparseNumberedBlockMatrix M,
                                     int idx,
                                     double s)

getCoordinates

public void getCoordinates(VectorNd coords)

Returns the current coordinates, if any, for this joint. Coordinates are returned in coords, whose size is set to the value returned by numCoordinates(). If the joint is connected to other bodies, the coordinates are inferred from the current TCD transform. Otherwise, they are obtained from stored internal values.

Parameters:

coords - returns the coordinate values

getStoredCoordinates

public void getStoredCoordinates(VectorNd coords)

Returns the coordinate values currently stored for this joint. These are the values that have been most recently set or computed, but may be independent of the current TCD transform. Coordinates are returned in coords, whose size is set to the value returned by numCoordinates().

Parameters:

coords - returns the coordinate values

getStoredTCD

public void getStoredTCD(RigidTransform3d TCD)

Returns the value of the TCD transform based on the coordinate values currently stored for this joint. This may be different from the value based on the poses of the attached bodies.

Parameters:

TCD - returns the stored TCD transform

getStoredTCD

public RigidTransform3d getStoredTCD()

setCoordinate

public void setCoordinate(int idx,
                          double value)

Sets the idx-th coordinate for this joint. If the joint is connected to other bodies, their poses are adjusted appropriately.

Parameters:

idx - index of the coordinate

value - new coordinate value

setCoordinateDeg

public void setCoordinateDeg(int idx,
                             double value)

Sets the idx-th coordinate for this joint. If the coordinate motion type is RigidBodyConstraint.MotionType.ROTARY, then the value is specified in degrees.

Parameters:

idx - index of the coordinate

value - new coordinate value

setCoordinates

public void setCoordinates(VectorNd coords)

Sets the current coordinates, if any, for this joint. If coordinates are not supported, this method does nothing. Otherwise, coords supplies the coordinates and should have a length >= numCoordinates(). If the joint is connected to other bodies, their poses are adjusted appropriately.

Parameters:

coords - new coordinate values

isCoordinateLocked

public boolean isCoordinateLocked(int idx)

Queries whether the idx-th coordinate for this joint is locked. See setCoordinateLocked(int, boolean) for details.

Parameters:

idx - index of the coordinate

Returns:

true if the coordinate is locked

setCoordinateLocked

public void setCoordinateLocked(int idx,
                                boolean locked)

Sets whether the idx-th coordinate for this joint is locked, meaning that it will hold its current value. Locking a coordinate will reduce the number of joint DOFs by one.

Parameters:

idx - index of the coordinate

locked - if true, sets the coordinate to be locked

coordinatesToTCD

public void coordinatesToTCD(RigidTransform3d TCD,
                             VectorNd coords)

Computes the TCD transform for a set of coordinates, if coordinates are supported. Otherwise this method does nothing.

Parameters:

TCD - returns the TCD transform

coords - supplies the coordinate values and must have a length >= numCoordinates().

getPosition

public void getPosition(Point3d pos)