SimTK::Constraint::NoSlip1D Class Reference
One non-holonomic constraint equation. More...
Inheritance diagram for SimTK::Constraint::NoSlip1D:
Public Member Functions | |
| NoSlip1D (MobilizedBody &caseBodyC, const Vec3 &P_C, const UnitVec3 &n_C, MobilizedBody &movingBody0, MobilizedBody &movingBody1) | |
| Define the up to three bodies involved in this constraint: the two "moving" bodies and a Case body, and a default contact point and no-slip direction in the Case body frame C. More... | |
| NoSlip1D () | |
| Default constructor creates an empty handle. More... | |
| void | setContactPoint (State &state, const Vec3 &point_C) const |
| Change the contact point at which this Constraint acts. More... | |
| void | setDirection (State &state, const UnitVec3 &direction_C) const |
| Change the no-slip direction along which this Constraint acts. More... | |
| const Vec3 & | getContactPoint (const State &state) const |
| Return from the given state the contact point, in the Case body frame. More... | |
| const UnitVec3 & | getDirection (const State &state) const |
| Return from the given state the no-slip direction, in the Case body frame. More... | |
| NoSlip1D & | setDirectionDisplayLength (Real) |
| For visualization only, set the length of the line used to show the no-slip direction. More... | |
| NoSlip1D & | setPointDisplayRadius (Real) |
| For visualization only, set the radius of the sphere used to show the contact point location. More... | |
| Real | getDirectionDisplayLength () const |
| Return the current value of the visualization line length for the no-slip direction. More... | |
| Real | getPointDisplayRadius () const |
| Return the current value of the radius for visualization of the contact point. More... | |
| NoSlip1D & | setDefaultContactPoint (const Vec3 &) |
| Change the default contact point; this is the initial value for for the actual contact point and is a topological change. More... | |
| NoSlip1D & | setDefaultDirection (const UnitVec3 &) |
| Change the default no-slip direction; this is the initial value for for the actual direction and is a topological change. More... | |
| MobilizedBodyIndex | getCaseMobilizedBodyIndex () const |
| Get the mobilized body index of the Case body that was set during construction. More... | |
| MobilizedBodyIndex | getMovingBodyMobilizedBodyIndex (int which) const |
| Get the mobilized body index of moving body 0 or moving body 1 that was set during construction. More... | |
| const UnitVec3 & | getDefaultDirection () const |
| Obtain the default value for the no-slip direction, expressed in the Case body frame. More... | |
| const Vec3 & | getDefaultContactPoint () const |
| Obtain the default value for the contact point, in the Case body frame. More... | |
| Real | getVelocityError (const State &state) const |
| Get the velocity error for this constraint equation, using configuration and velocity information from the given state, which must already have been realized through Velocity stage. More... | |
| Real | getAccelerationError (const State &) const |
| Get the acceleration error for this constraint equation, using configuration, velocity, and acceleration information from the given state, which must already have been realized through Acceleration stage. More... | |
| Real | getMultiplier (const State &) const |
| Get the Lagrange multiplier for this constraint equation, using configuration, velocity, and acceleration information from the given state, which must already have been realized through Acceleration stage. More... | |
| Real | getForceAtContactPoint (const State &) const |
| Determine the constraint force currently being generated by this constraint. More... | |
| Public Member Functions inherited from SimTK::Constraint | |
| Constraint () | |
| Default constructor creates an empty Constraint handle that can be used to reference any Constraint. More... | |
| Constraint (ConstraintImpl *r) | |
| For internal use: construct a new Constraint handle referencing a particular implementation object. More... | |
| void | disable (State &) const |
| Disable this Constraint, effectively removing it from the system. More... | |
| void | enable (State &) const |
| Enable this Constraint, without necessarily satisfying it. More... | |
| bool | isDisabled (const State &) const |
| Test whether this constraint is currently disabled in the supplied State. More... | |
| bool | isDisabledByDefault () const |
| Test whether this Constraint is disabled by default in which case it must be explicitly enabled before it will take effect. More... | |
| void | setDisabledByDefault (bool shouldBeDisabled) |
| Normally Constraints are enabled when defined and can be disabled later. More... | |
| operator ConstraintIndex () const | |
| This is an implicit conversion from Constraint to ConstraintIndex when needed. More... | |
| const SimbodyMatterSubsystem & | getMatterSubsystem () const |
| Get a const reference to the matter subsystem that contains this Constraint. More... | |
| SimbodyMatterSubsystem & | updMatterSubsystem () |
| Assuming you have writable access to this Constraint, get a writable reference to the containing matter subsystem. More... | |
| ConstraintIndex | getConstraintIndex () const |
| Get the ConstraintIndex that was assigned to this Constraint when it was added to the matter subsystem. More... | |
| bool | isInSubsystem () const |
| Test whether this Constraint is contained within a matter subsystem. More... | |
| bool | isInSameSubsystem (const MobilizedBody &mobod) const |
| Test whether the supplied MobilizedBody is in the same matter subsystem as this Constraint. More... | |
| int | getNumConstrainedBodies () const |
| Return the number of unique bodies directly restricted by this constraint. More... | |
| const MobilizedBody & | getMobilizedBodyFromConstrainedBody (ConstrainedBodyIndex consBodyIx) const |
| Return a const reference to the actual MobilizedBody corresponding to one of the Constrained Bodies included in the count returned by getNumConstrainedBodies(). More... | |
| const MobilizedBody & | getAncestorMobilizedBody () const |
| Return a const reference to the actual MobilizedBody which is serving as the Ancestor body for the constrained bodies in this Constraint. More... | |
| int | getNumConstrainedMobilizers () const |
| Return the number of unique mobilizers directly restricted by this Constraint. More... | |
| const MobilizedBody & | getMobilizedBodyFromConstrainedMobilizer (ConstrainedMobilizerIndex consMobilizerIx) const |
| Return a const reference to the actual MobilizedBody corresponding to one of the Constrained Mobilizers included in the count returned by getNumConstrainedMobilizers(). More... | |
| const SimbodyMatterSubtree & | getSubtree () const |
| Return a subtree object indicating which parts of the multibody tree are potentially affected by this Constraint. More... | |
| int | getNumConstrainedQ (const State &, ConstrainedMobilizerIndex) const |
| Return the number of constrainable generalized coordinates q associated with a particular constrained mobilizer. More... | |
| int | getNumConstrainedU (const State &, ConstrainedMobilizerIndex) const |
| Return the number of constrainable mobilities u associated with a particular constrained mobilizer. More... | |
| ConstrainedUIndex | getConstrainedUIndex (const State &, ConstrainedMobilizerIndex, MobilizerUIndex which) const |
| Return the index into the constrained mobilities u array corresponding to a particular mobility of the indicated ConstrainedMobilizer. More... | |
| ConstrainedQIndex | getConstrainedQIndex (const State &, ConstrainedMobilizerIndex, MobilizerQIndex which) const |
| Return the index into the constrained coordinates q array corresponding to a particular coordinate of the indicated ConstrainedMobilizer. More... | |
| int | getNumConstrainedQ (const State &) const |
| Return the sum of the number of coordinates q associated with each of the constrained mobilizers. More... | |
| int | getNumConstrainedU (const State &) const |
| Return the sum of the number of mobilities u associated with each of the constrained mobilizers. More... | |
| QIndex | getQIndexOfConstrainedQ (const State &state, ConstrainedQIndex consQIndex) const |
| Map one of this Constraint's constrained q's to the corresponding index within the matter subsystem's whole q vector. More... | |
| UIndex | getUIndexOfConstrainedU (const State &state, ConstrainedUIndex consUIndex) const |
| Map one of this Constraint's constrained U's (or mobilities) to the corresponding index within the matter subsystem's whole u vector. More... | |
| void | getNumConstraintEquationsInUse (const State &state, int &mp, int &mv, int &ma) const |
| Find out how many holonomic (position), nonholonomic (velocity), and acceleration-only constraint equations are currently being generated by this Constraint. More... | |
| void | getIndexOfMultipliersInUse (const State &state, MultiplierIndex &px0, MultiplierIndex &vx0, MultiplierIndex &ax0) const |
| Return the start of the blocks of multipliers (or acceleration errors) assigned to this Constraint. More... | |
| void | setMyPartInConstraintSpaceVector (const State &state, const Vector &myPart, Vector &constraintSpace) const |
| Set the part of a complete constraint-space vector that belongs to this constraint. More... | |
| void | getMyPartFromConstraintSpaceVector (const State &state, const Vector &constraintSpace, Vector &myPart) const |
| Get the part of a complete constraint-space vector that belongs to this constraint. More... | |
| Vector | getPositionErrorsAsVector (const State &) const |
| Get a Vector containing the position errors. More... | |
| Vector | calcPositionErrorFromQ (const State &, const Vector &q) const |
| Matrix | calcPositionConstraintMatrixP (const State &) const |
| Matrix | calcPositionConstraintMatrixPt (const State &) const |
| Matrix | calcPositionConstraintMatrixPNInv (const State &) const |
| void | calcConstraintForcesFromMultipliers (const State &, const Vector &lambda, Vector_< SpatialVec > &bodyForcesInA, Vector &mobilityForces) const |
| This operator calculates this constraint's body and mobility forces given the complete set of multipliers lambda for this Constraint. More... | |
| Vector | getVelocityErrorsAsVector (const State &) const |
| Get a Vector containing the velocity errors. More... | |
| Vector | calcVelocityErrorFromU (const State &, const Vector &u) const |
| Matrix | calcVelocityConstraintMatrixV (const State &) const |
| Matrix | calcVelocityConstraintMatrixVt (const State &) const |
| Vector | getAccelerationErrorsAsVector (const State &) const |
| Get a Vector containing the acceleration errors. More... | |
| Vector | calcAccelerationErrorFromUDot (const State &, const Vector &udot) const |
| Vector | getMultipliersAsVector (const State &) const |
| Get a Vector containing the Lagrange multipliers. More... | |
| void | getConstraintForcesAsVectors (const State &state, Vector_< SpatialVec > &bodyForcesInG, Vector &mobilityForces) const |
| Given a State realized through Acceleration stage, return the forces that were applied to the system by this Constraint, with body forces expressed in Ground. More... | |
| Vector_< SpatialVec > | getConstrainedBodyForcesAsVector (const State &state) const |
| For convenience, returns constrained body forces as the function return. More... | |
| Vector | getConstrainedMobilityForcesAsVector (const State &state) const |
| For convenience, returns constrained mobility forces as the function return. More... | |
| Real | calcPower (const State &state) const |
| Calculate the power being applied by this Constraint to the system. More... | |
| Matrix | calcAccelerationConstraintMatrixA (const State &) const |
| Matrix | calcAccelerationConstraintMatrixAt (const State &) const |
| void | setIsConditional (bool isConditional) |
| (Advanced) Mark this constraint as one that is only conditionally active. More... | |
| bool | isConditional () const |
| (Advanced) Get the value of the isConditional flag. More... | |
| Public Member Functions inherited from SimTK::PIMPLHandle< Constraint, ConstraintImpl, true > | |
| bool | isEmptyHandle () const |
| Returns true if this handle is empty, that is, does not refer to any implementation object. More... | |
| bool | isOwnerHandle () const |
| Returns true if this handle is the owner of the implementation object to which it refers. More... | |
| bool | isSameHandle (const Constraint &other) const |
| Determine whether the supplied handle is the same object as "this" PIMPLHandle. More... | |
| void | disown (Constraint &newOwner) |
| Give up ownership of the implementation to an empty handle. More... | |
| PIMPLHandle & | referenceAssign (const Constraint &source) |
| "Copy" assignment but with shallow (pointer) semantics. More... | |
| PIMPLHandle & | copyAssign (const Constraint &source) |
| This is real copy assignment, with ordinary C++ object ("value") semantics. More... | |
| void | clearHandle () |
| Make this an empty handle, deleting the implementation object if this handle is the owner of it. More... | |
| const ConstraintImpl & | getImpl () const |
| Get a const reference to the implementation associated with this Handle. More... | |
| ConstraintImpl & | updImpl () |
| Get a writable reference to the implementation associated with this Handle. More... | |
| int | getImplHandleCount () const |
| Return the number of handles the implementation believes are referencing it. More... | |
Additional Inherited Members | |
| Public Types inherited from SimTK::Constraint | |
| typedef Rod | ConstantDistance |
| Synonym for Rod constraint. More... | |
| typedef Ball | CoincidentPoints |
| Synonym for Ball constraint. More... | |
| typedef Ball | Spherical |
| Synonym for Ball constraint. More... | |
| typedef Weld | CoincidentFrames |
| Public Types inherited from SimTK::PIMPLHandle< Constraint, ConstraintImpl, true > | |
| typedef PIMPLHandle< Constraint, ConstraintImpl, PTR > | HandleBase |
| typedef HandleBase | ParentHandle |
| Protected Member Functions inherited from SimTK::PIMPLHandle< Constraint, ConstraintImpl, true > | |
| PIMPLHandle () | |
| The default constructor makes this an empty handle. More... | |
| PIMPLHandle (ConstraintImpl *p) | |
| This provides consruction of a handle referencing an existing implementation object. More... | |
| PIMPLHandle (const PIMPLHandle &source) | |
| The copy constructor makes either a deep (value) or shallow (reference) copy of the supplied source PIMPL object, based on whether this is a "pointer
semantics" (PTR=true) or "object (value) semantics" (PTR=false, default) class. More... | |
| ~PIMPLHandle () | |
| Note that the destructor is non-virtual. More... | |
| PIMPLHandle & | operator= (const PIMPLHandle &source) |
| Copy assignment makes the current handle either a deep (value) or shallow (reference) copy of the supplied source PIMPL object, based on whether this is a "pointer sematics" (PTR=true) or "object (value) semantics" (PTR=false, default) class. More... | |
| void | setImpl (ConstraintImpl *p) |
| Set the implementation for this empty handle. More... | |
| bool | hasSameImplementation (const Constraint &other) const |
| Determine whether the supplied handle is a reference to the same implementation object as is referenced by "this" PIMPLHandle. More... | |
Detailed Description
One non-holonomic constraint equation.
There is a contact point P and a no-slip direction n fixed in a case body C. There are two moving bodies B0 and B1. The material point of B0 and the material point of B1 which are each coincident with the contact point P must have identical velocities in C, along the direction n. This can be used to implement simple rolling contact between disks, such as occurs in gear trains.
The assembly condition is the same as the run-time constraint: the velocities must be made to match.
Constructor & Destructor Documentation
◆ NoSlip1D() [1/2]
| SimTK::Constraint::NoSlip1D::NoSlip1D | ( | MobilizedBody & | caseBodyC, |
| const Vec3 & | P_C, | ||
| const UnitVec3 & | n_C, | ||
| MobilizedBody & | movingBody0, | ||
| MobilizedBody & | movingBody1 | ||
| ) |
Define the up to three bodies involved in this constraint: the two "moving" bodies and a Case body, and a default contact point and no-slip direction in the Case body frame C.
(If you are modeling gears then the Case is the gearbox.) The case serves to define the contact geometry but no forces are applied to it. It is OK for the Case body to be the same body as one of the moving bodies.
◆ NoSlip1D() [2/2]
|
inline |
Default constructor creates an empty handle.
Member Function Documentation
◆ setContactPoint()
Change the contact point at which this Constraint acts.
Provide the station location in the Case body local frame. This overrides the default point that was supplied on construction. This is an Instance-stage change.
◆ setDirection()
| void SimTK::Constraint::NoSlip1D::setDirection | ( | State & | state, |
| const UnitVec3 & | direction_C | ||
| ) | const |
Change the no-slip direction along which this Constraint acts.
Provide the direction unit vector in the Case body local frame. This overrides the default direction that was supplied on construction. This is an Instance-stage change.
◆ getContactPoint()
Return from the given state the contact point, in the Case body frame.
◆ getDirection()
Return from the given state the no-slip direction, in the Case body frame.
◆ setDirectionDisplayLength()
For visualization only, set the length of the line used to show the no-slip direction.
◆ setPointDisplayRadius()
For visualization only, set the radius of the sphere used to show the contact point location.
◆ getDirectionDisplayLength()
| Real SimTK::Constraint::NoSlip1D::getDirectionDisplayLength | ( | ) | const |
Return the current value of the visualization line length for the no-slip direction.
◆ getPointDisplayRadius()
| Real SimTK::Constraint::NoSlip1D::getPointDisplayRadius | ( | ) | const |
Return the current value of the radius for visualization of the contact point.
◆ setDefaultContactPoint()
Change the default contact point; this is the initial value for for the actual contact point and is a topological change.
◆ setDefaultDirection()
Change the default no-slip direction; this is the initial value for for the actual direction and is a topological change.
◆ getCaseMobilizedBodyIndex()
| MobilizedBodyIndex SimTK::Constraint::NoSlip1D::getCaseMobilizedBodyIndex | ( | ) | const |
Get the mobilized body index of the Case body that was set during construction.
◆ getMovingBodyMobilizedBodyIndex()
| MobilizedBodyIndex SimTK::Constraint::NoSlip1D::getMovingBodyMobilizedBodyIndex | ( | int | which | ) | const |
Get the mobilized body index of moving body 0 or moving body 1 that was set during construction.
Set which to 0 or 1 accordingly.
◆ getDefaultDirection()
| const UnitVec3& SimTK::Constraint::NoSlip1D::getDefaultDirection | ( | ) | const |
Obtain the default value for the no-slip direction, expressed in the Case body frame.
◆ getDefaultContactPoint()
| const Vec3& SimTK::Constraint::NoSlip1D::getDefaultContactPoint | ( | ) | const |
Obtain the default value for the contact point, in the Case body frame.
◆ getVelocityError()
Get the velocity error for this constraint equation, using configuration and velocity information from the given state, which must already have been realized through Velocity stage.
◆ getAccelerationError()
Get the acceleration error for this constraint equation, using configuration, velocity, and acceleration information from the given state, which must already have been realized through Acceleration stage.
◆ getMultiplier()
Get the Lagrange multiplier for this constraint equation, using configuration, velocity, and acceleration information from the given state, which must already have been realized through Acceleration stage.
While this is linearly related to the constraint force it may have arbitrary sign and scaling; if you want an actual force use getForceAtContactPoint() instead.
◆ getForceAtContactPoint()
Determine the constraint force currently being generated by this constraint.
The force is as applied to the second moving body, that is, moving body 1, and is applied along the no-slip direction vector.
The documentation for this class was generated from the following file:
