Description

Class for Rigid Bodies.

A rigid body is an entity with mass and inertia properties moving in the 3D space. Optionally, an object of the ChBody class (or derived) can:

  • be involved in collision, if a collision model is provided (Collisions) and the collision is enabled;
  • be visualized, if a visual model is provided and a proper visualization system is available (Visualization System);
  • be constrained by means of ChLink objects (Links);
  • be loaded by ChLoad objects (Loads);
  • be used in coordinate transformation, being itself inherited from ChFrameMoving;

Location and orientation of the ChBody refer to its Center of Mass (CoM). Since no additional frame is available, also visual and collision shapes refer to the same frame. Derived classes might offer additional frames (e.g. ChBodyAuxRef).

Further info at the Rigid Bodies manual page.

#include <ChBody.h>

Inheritance diagram for chrono::ChBody:
Collaboration diagram for chrono::ChBody:

Public Member Functions

 ChBody (const ChBody &other)
 
virtual ChBodyClone () const override
 "Virtual" copy constructor (covariant return type).
 
void SetFixed (bool state)
 Sets the 'fixed' state of the body. More...
 
bool IsFixed () const
 Return true if this body is fixed to ground.
 
void EnableCollision (bool state)
 Enable/disable the collision for this rigid body.
 
virtual bool IsCollisionEnabled () const override
 Return true if collision is enabled for this body.
 
void SetLimitSpeed (bool state)
 Enable the maximum linear speed limit (default: false).
 
void SetUseGyroTorque (bool state)
 Enable/disable the gyroscopic torque (quadratic term). More...
 
bool IsUsingGyroTorque () const
 Return true if gyroscopic torque is used (default=true).
 
void SetSleepingAllowed (bool state)
 Enable/disable option for setting bodies to 'sleep'. More...
 
bool IsSleepingAllowed () const
 Return true if 'sleep' mode is allowed for this specific body.
 
void SetSleeping (bool state)
 Force the body in sleeping mode or not. More...
 
bool IsSleeping () const
 Return true if this body is currently in 'sleep' mode.
 
bool TrySleeping ()
 Test if a body could go in sleeping state if requirements are satisfied. More...
 
virtual bool IsActive () const override
 Return true if the body is currently active and therefore included into the system solver. More...
 
unsigned int GetIndex ()
 Get the unique sequential body index (internal use only).
 
virtual unsigned int GetNumCoordsPosLevel () override
 Number of coordinates of body: 7 because uses quaternions for rotation.
 
virtual unsigned int GetNumCoordsVelLevel () override
 Number of coordinates of body: 6 because derivatives use angular velocity.
 
virtual ChVariablesVariables () override
 Return a reference to the encapsulated ChVariablesBody, representing states (pos, speed, or accel.) and forces. More...
 
void ForceToRest () override
 Set no speed and no accelerations (but does not change the position).
 
virtual void AddCollisionModelsToSystem (ChCollisionSystem *coll_sys) const override
 Add the body collision model (if any) to the provided collision system.
 
virtual void RemoveCollisionModelsFromSystem (ChCollisionSystem *coll_sys) const override
 Remove the body collision model (if any) from the provided collision system.
 
virtual void SyncCollisionModels () override
 Synchronize the position and bounding box of the body collision model (if any).
 
virtual const ChFrameMovingGetFrameCOMToAbs () const
 Get the rigid body coordinate system that represents the GOG (Center of Gravity). More...
 
virtual const ChFrameMovingGetFrameRefToAbs () const
 Get the rigid body coordinate system that is used for defining the collision shapes and the ChMarker objects. More...
 
virtual ChFrame GetVisualModelFrame (unsigned int nclone=0) override
 Get the reference frame (expressed in and relative to the absolute frame) of the visual model. More...
 
virtual ChAABB GetTotalAABB () override
 Get the axis-aligned bounding (AABB) box of the object. More...
 
void AddMarker (std::shared_ptr< ChMarker > amarker)
 Attach a marker to this body.
 
void AddForce (std::shared_ptr< ChForce > aforce)
 Attach a force to this body.
 
void RemoveMarker (std::shared_ptr< ChMarker > amarker)
 Remove a specific marker from this body. More...
 
void RemoveForce (std::shared_ptr< ChForce > aforce)
 Remove a specific force from this body. More...
 
void RemoveAllForces ()
 Remove all markers at once. More...
 
void RemoveAllMarkers ()
 Remove all markers at once. More...
 
std::shared_ptr< ChMarkerSearchMarker (const std::string &name) const
 Find a marker by its name.
 
std::shared_ptr< ChMarkerSearchMarker (int id) const
 Find a marker by its identifier.
 
std::shared_ptr< ChForceSearchForce (const std::string &name) const
 Find a force by its name.
 
const std::vector< std::shared_ptr< ChMarker > > & GetMarkers () const
 Gets the list of children markers. More...
 
const std::vector< std::shared_ptr< ChForce > > & GetForces () const
 Gets the list of children forces. More...
 
void SetMass (double newmass)
 Set the body mass. More...
 
double GetMass ()
 Get the body mass.
 
void SetInertia (const ChMatrix33<> &newXInertia)
 Set the inertia tensor of the body. More...
 
const ChMatrix33GetInertia () const
 Get the inertia tensor, expressed in the local coordinate system. More...
 
const ChMatrix33GetInvInertia () const
 Get the inverse of the inertia matrix.
 
void SetInertiaXX (const ChVector3d &iner)
 Set the diagonal part of the inertia tensor (Ixx, Iyy, Izz values). More...
 
ChVector3d GetInertiaXX () const
 Get the diagonal part of the inertia tensor (Ixx, Iyy, Izz values). More...
 
void SetInertiaXY (const ChVector3d &iner)
 Set the off-diagonal part of the inertia tensor (Ixy, Ixz, Iyz values). More...
 
ChVector3d GetInertiaXY () const
 Get the extra-diagonal part of the inertia tensor (Ixy, Ixz, Iyz values). More...
 
void SetMaxLinVel (float m_max_speed)
 Set the maximum linear speed (beyond this limit it will be clamped). More...
 
float GetMaxLinVel () const
 
void SetMaxAngVel (float m_max_wvel)
 Set the maximum angular speed (beyond this limit it will be clamped). More...
 
float GetMaxAngVel () const
 
void ClampSpeed ()
 Clamp the body speed to the provided limits. More...
 
void SetSleepTime (float m_t)
 Set the amount of time which must pass before going automatically in sleep mode when the body has very small movements.
 
float GetSleepTime () const
 
void SetSleepMinLinVel (float m_t)
 Set the max linear speed to be kept for 'sleep_time' before freezing.
 
float GetSleepMinLinVel () const
 
void SetSleepMinAngVel (float m_t)
 Set the max linear speed to be kept for 'sleep_time' before freezing.
 
float GetSleepMinAngVel () const
 
void ComputeQInertia (ChMatrix44<> &mQInertia)
 Computes the 4x4 inertia tensor in quaternion space, if needed.
 
void ComputeGyro ()
 Computes the gyroscopic torque. More...
 
void AccumulateForce (const ChVector3d &force, const ChVector3d &appl_point, bool local)
 Add an applied force to the body's accumulator (as an increment). More...
 
void AccumulateTorque (const ChVector3d &torque, bool local)
 Add an applied torque to the body's accumulator (as an increment). More...
 
void EmptyAccumulators ()
 Clear the force and torque accumulators.
 
const ChVector3dGetAccumulatedForce () const
 Return the current value of the accumulator force. More...
 
const ChVector3dGetAccumulatedTorque () const
 Return the current value of the accumulator torque. More...
 
void UpdateMarkers (double mytime)
 Update all children markers of the rigid body, at current body state.
 
void UpdateForces (double mytime)
 Update all children forces of the rigid body, at current body state.
 
void UpdateTime (double mytime)
 Update local time of rigid body, and time-dependent data.
 
virtual void Update (double mytime, bool update_assets=true) override
 Update all auxiliary data of the rigid body and of its children (markers, forces..), at given time.
 
virtual void Update (bool update_assets=true) override
 Update all auxiliary data of the rigid body and of its children (markers, forces..)
 
ChVector3d GetAppliedForce ()
 Return the resultant applied force on the body. More...
 
ChVector3d GetAppliedTorque ()
 Return the resultant applied torque on the body. More...
 
ChVector3d GetContactForce ()
 Get the resultant contact force acting on this body.
 
ChVector3d GetContactTorque ()
 Get the resultant contact torque acting on this body.
 
virtual ChPhysicsItemGetPhysicsItem () override
 This is only for backward compatibility.
 
virtual void ArchiveOut (ChArchiveOut &archive_out) override
 Method to allow serialization of transient data to archives.
 
virtual void ArchiveIn (ChArchiveIn &archive_in) override
 Method to allow deserialization of transient data from archives. More...
 
virtual void LoadableGetVariables (std::vector< ChVariables * > &mvars) override
 Get the pointers to the contained ChVariables, appending to the mvars vector.
 
virtual void LoadableStateIncrement (const unsigned int off_x, ChState &x_new, const ChState &x, const unsigned int off_v, const ChStateDelta &Dv) override
 Increment all DOFs using a delta.
 
virtual void LoadableGetStateBlockPosLevel (int block_offset, ChState &mD) override
 Gets all the DOFs packed in a single vector (position part)
 
virtual void LoadableGetStateBlockVelLevel (int block_offset, ChStateDelta &mD) override
 Gets all the DOFs packed in a single vector (speed part)
 
virtual void ComputeNF (const double U, const double V, const double W, ChVectorDynamic<> &Qi, double &detJ, const ChVectorDynamic<> &F, ChVectorDynamic<> *state_x, ChVectorDynamic<> *state_w) override
 Evaluate Q=N'*F, for Q generalized lagrangian load, where N is some type of matrix evaluated at point P(U,V,W) assumed in absolute coordinates, and F is a load assumed in absolute coordinates. More...
 
- Public Member Functions inherited from chrono::ChPhysicsItem
 ChPhysicsItem (const ChPhysicsItem &other)
 
ChSystemGetSystem () const
 Get the pointer to the parent ChSystem().
 
virtual void SetSystem (ChSystem *m_system)
 Set the pointer to the parent ChSystem(). More...
 
void AddVisualModel (std::shared_ptr< ChVisualModel > model)
 Add an (optional) visualization model. More...
 
std::shared_ptr< ChVisualModelGetVisualModel () const
 Access the visualization model (if any). More...
 
void AddVisualShape (std::shared_ptr< ChVisualShape > shape, const ChFrame<> &frame=ChFrame<>())
 Add the specified visual shape to the visualization model. More...
 
std::shared_ptr< ChVisualShapeGetVisualShape (unsigned int i) const
 Access the specified visualization shape in the visualization model (if any). More...
 
void AddVisualShapeFEA (std::shared_ptr< ChVisualShapeFEA > shapeFEA)
 Add the specified FEA visualization object to the visualization model. More...
 
std::shared_ptr< ChVisualShapeFEAGetVisualShapeFEA (unsigned int i) const
 Access the specified FEA visualization object in the visualization model (if any). More...
 
virtual unsigned int GetNumVisualModelClones () const
 Return the number of clones of the visual model associated with this physics item. More...
 
void AddCamera (std::shared_ptr< ChCamera > camera)
 Attach a ChCamera to this physical item. More...
 
std::vector< std::shared_ptr< ChCamera > > GetCameras () const
 Get the set of cameras attached to this physics item.
 
virtual void GetCenter (ChVector3d &mcenter)
 Get a symbolic 'center' of the object. More...
 
virtual void Setup ()
 This might recompute the number of coordinates, DOFs, constraints, in case this might change (ex in ChAssembly), as well as state offsets of contained items (ex in ChMesh)
 
virtual unsigned int GetNumConstraints ()
 Get the number of scalar constraints.
 
virtual unsigned int GetNumConstraintsBilateral ()
 Get the number of bilateral scalar constraints.
 
virtual unsigned int GetNumConstraintsUnilateral ()
 Get the number of unilateral scalar constraints.
 
unsigned int GetOffset_x ()
 Get offset in the state vector (position part)
 
unsigned int GetOffset_w ()
 Get offset in the state vector (speed part)
 
unsigned int GetOffset_L ()
 Get offset in the lagrangian multipliers.
 
void SetOffset_x (const unsigned int moff)
 Set offset in the state vector (position part) Note: only the ChSystem::Setup function should use this.
 
void SetOffset_w (const unsigned int moff)
 Set offset in the state vector (speed part) Note: only the ChSystem::Setup function should use this.
 
void SetOffset_L (const unsigned int moff)
 Set offset in the lagrangian multipliers Note: only the ChSystem::Setup function should use this.
 
virtual void IntStateGatherReactions (const unsigned int off_L, ChVectorDynamic<> &L)
 From item's reaction forces to global reaction vector. More...
 
virtual void IntStateScatterReactions (const unsigned int off_L, const ChVectorDynamic<> &L)
 From global reaction vector to item's reaction forces. More...
 
virtual void IntLoadResidual_CqL (const unsigned int off_L, ChVectorDynamic<> &R, const ChVectorDynamic<> &L, const double c)
 Takes the term Cq'*L, scale and adds to R at given offset: R += c*Cq'*L. More...
 
virtual void IntLoadConstraint_C (const unsigned int off, ChVectorDynamic<> &Qc, const double c, bool do_clamp, double recovery_clamp)
 Takes the term C, scale and adds to Qc at given offset: Qc += c*C. More...
 
virtual void IntLoadConstraint_Ct (const unsigned int off, ChVectorDynamic<> &Qc, const double c)
 Takes the term Ct, scale and adds to Qc at given offset: Qc += c*Ct. More...
 
virtual void InjectConstraints (ChSystemDescriptor &descriptor)
 Register with the given system descriptor any ChConstraint objects associated with this item.
 
virtual void LoadConstraintJacobians ()
 Compute and load current Jacobians in encapsulated ChConstraint objects.
 
virtual void InjectKRMMatrices (ChSystemDescriptor &descriptor)
 Register with the given system descriptor any ChKRMBlock objects associated with this item.
 
virtual void LoadKRMMatrices (double Kfactor, double Rfactor, double Mfactor)
 Compute and load current stiffnes (K), damping (R), and mass (M) matrices in encapsulated ChKRMBlock objects. More...
 
virtual void ConstraintsBiReset ()
 Sets to zero the known term (b_i) of encapsulated ChConstraints.
 
virtual void ConstraintsBiLoad_C (double factor=1, double recovery_clamp=0.1, bool do_clamp=false)
 Adds the current C (constraint violation) to the known term (b_i) of encapsulated ChConstraints.
 
virtual void ConstraintsBiLoad_Ct (double factor=1)
 Adds the current Ct (partial t-derivative, as in C_dt=0-> [Cq]*q_dt=-Ct) to the known term (b_i) of encapsulated ChConstraints.
 
virtual void ConstraintsBiLoad_Qc (double factor=1)
 Adds the current Qc (the vector of C_dtdt=0 -> [Cq]*q_dtdt=Qc ) to the known term (b_i) of encapsulated ChConstraints.
 
virtual void ConstraintsFbLoadForces (double factor=1)
 Adds the current link-forces, if any, (caused by springs, etc.) to the 'fb' vectors of the ChVariables referenced by encapsulated ChConstraints.
 
virtual void ConstraintsFetch_react (double factor=1)
 Fetches the reactions from the lagrangian multiplier (l_i) of encapsulated ChConstraints. More...
 
- Public Member Functions inherited from chrono::ChObj
 ChObj (const ChObj &other)
 
int GetIdentifier () const
 Get the unique integer identifier of this object. More...
 
void SetTag (int tag)
 Set an object integer tag (default: -1). More...
 
int GetTag () const
 Get the tag of this object.
 
void SetName (const std::string &myname)
 Set the name of this object.
 
std::string GetName () const
 Get the name of this object.
 
double GetChTime () const
 Gets the simulation time of this object.
 
void SetChTime (double m_time)
 Sets the simulation time of this object.
 
virtual std::string & ArchiveContainerName ()
 
- Public Member Functions inherited from chrono::ChBodyFrame
 ChBodyFrame (const ChBodyFrame &other)
 
ChWrenchd AppliedForceLocalToWrenchParent (const ChVector3d &force, const ChVector3d &appl_point)
 Transform a force applied to a point on the body to a force and moment at the frame origin. More...
 
ChWrenchd AppliedForceParentToWrenchParent (const ChVector3d &force, const ChVector3d &appl_point)
 Transform a force applied to a point on the body to a force and moment at the frame origin. More...
 
- Public Member Functions inherited from chrono::ChFrameMoving< double >
 ChFrameMoving (const ChVector3< double > &mv=ChVector3< double >(0, 0, 0), const ChQuaternion< double > &mq=ChQuaternion< double >(1, 0, 0, 0))
 Construct from pos and rot (as a quaternion).
 
 ChFrameMoving (const ChVector3< double > &mv, const ChMatrix33< double > &ma)
 Construct from pos and rotation (as a 3x3 matrix).
 
 ChFrameMoving (const ChCoordsys< double > &mc)
 Construct from a coordsys.
 
 ChFrameMoving (const ChFrame< double > &mc)
 Construct from a frame.
 
 ChFrameMoving (const ChFrameMoving< double > &other)
 Copy constructor, build from another moving frame.
 
virtual ~ChFrameMoving ()
 Destructor.
 
ChFrameMoving< double > & operator= (const ChFrameMoving< double > &other)
 Assignment operator: copy from another moving frame.
 
ChFrameMoving< double > & operator= (const ChFrame< double > &other)
 Assignment operator: copy from another frame.
 
bool operator== (const ChFrameMoving< double > &other) const
 Returns true for identical frames.
 
bool operator!= (const ChFrameMoving< double > &other) const
 Returns true for different frames.
 
ChFrameMoving< double > operator>> (const ChFrameMoving< double > &F) const
 Transform another frame through this frame. More...
 
ChFrameMoving< double > operator* (const ChFrameMoving< double > &F) const
 Transform another frame through this frame. More...
 
ChFrameMoving< double > & operator>>= (const ChFrameMoving< double > &F)
 Transform this frame by pre-multiplication with another frame. More...
 
ChFrameMoving< double > & operator>>= (const ChVector3< double > &v)
 Transform this frame by pre-multiplication with a given vector (translate frame).
 
ChFrameMoving< double > & operator>>= (const ChQuaternion< double > &q)
 Transform this frame by pre-multiplication with a given quaternion (rotate frame).
 
ChFrameMoving< double > & operator>>= (const ChCoordsys< double > &C)
 Transform this frame by pre-multiplication with a given coordinate system.
 
ChFrameMoving< double > & operator>>= (const ChFrame< double > &F)
 Transform this frame by pre-multiplication with another frame.
 
ChFrameMoving< double > & operator*= (const ChFrameMoving< double > &F)
 Transform this frame by post-multiplication with another frame. More...
 
ChCoordsys< double > & GetCoordsysDt ()
 Return both rotation and translation velocities as a ChCoordsys object.
 
const ChCoordsys< double > & GetCoordsysDt () const
 
ChCoordsys< double > & GetCoordsysDt2 ()
 Return both rotation and translation accelerations as a ChCoordsys object.
 
const ChCoordsys< double > & GetCoordsysDt2 () const
 
ChVector3< double > & GetPosDt ()
 Return the linear velocity.
 
const ChVector3< double > & GetPosDt () const
 
const ChVector3< double > & GetLinVel () const
 Return the linear velocity.
 
ChVector3< double > & GetPosDt2 ()
 Return the linear acceleration.
 
const ChVector3< double > & GetPosDt2 () const
 
const ChVector3< double > & GetLinAcc () const
 Return the linear acceleration.
 
ChQuaternion< double > & GetRotDt ()
 Return the rotation velocity as a quaternion.
 
const ChQuaternion< double > & GetRotDt () const
 
ChQuaternion< double > & GetRotDt2 ()
 Return the rotation acceleration as a quaternion.
 
const ChQuaternion< double > & GetRotDt2 () const
 
ChVector3< double > GetAngVelLocal () const
 Compute the angular velocity (expressed in local coords).
 
ChVector3< double > GetAngVelParent () const
 Compute the actual angular velocity (expressed in parent coords).
 
ChVector3< double > GetAngAccLocal () const
 Compute the actual angular acceleration (expressed in local coords).
 
ChVector3< double > GetAngAccParent () const
 Compute the actual angular acceleration (expressed in parent coords).
 
virtual void SetCoordsysDt (const ChCoordsys< double > &csys_dt)
 Set both linear and rotation velocities as a single ChCoordsys derivative.
 
virtual void SetPosDt (const ChVector3< double > &vel)
 Set the linear velocity.
 
virtual void SetLinVel (const ChVector3< double > &vel)
 Set the linear velocity.
 
virtual void SetRotDt (const ChQuaternion< double > &q_dt)
 Set the rotation velocity as a quaternion derivative. More...
 
virtual void SetAngVelLocal (const ChVector3< double > &w)
 Set the rotation velocity from the given angular velocity (expressed in local coordinates).
 
virtual void SetAngVelParent (const ChVector3< double > &w)
 Set the rotation velocity from given angular velocity (expressed in parent coordinates).
 
virtual void SetCoordsysDt2 (const ChCoordsys< double > &csys_dtdt)
 Set the linear and rotation accelerations as a single ChCoordsys derivative.
 
virtual void SetPosDt2 (const ChVector3< double > &acc)
 Set the linear acceleration.
 
virtual void SetLinAcc (const ChVector3< double > &acc)
 Set the linear acceleration.
 
virtual void SetRotDt2 (const ChQuaternion< double > &q_dtdt)
 Set the rotation acceleration as a quaternion derivative. More...
 
virtual void SetAngAccLocal (const ChVector3< double > &a)
 Set the rotation acceleration from given angular acceleration (expressed in local coordinates). More...
 
virtual void SetAngAccParent (const ChVector3< double > &a)
 Set the rotation acceleration from given angular acceleration (expressed in parent coordinates).
 
void ComputeRotMatDt (ChMatrix33< double > &R_dt) const
 Compute the time derivative of the rotation matrix.
 
void ComputeRotMatDt2 (ChMatrix33< double > &R_dtdt)
 Compute the second time derivative of the rotation matrix.
 
ChMatrix33< double > GetRotMatDt ()
 Return the time derivative of the rotation matrix.
 
ChMatrix33< double > GetRotMatDt2 ()
 Return the second time derivative of the rotation matrix.
 
void ConcatenatePreTransformation (const ChFrameMoving< double > &F)
 Apply a transformation (rotation and translation) represented by another frame. More...
 
void ConcatenatePostTransformation (const ChFrameMoving< double > &F)
 Apply a transformation (rotation and translation) represented by another frame F in local coordinate. More...
 
ChVector3< double > PointSpeedLocalToParent (const ChVector3< double > &localpos) const
 Return the velocity in the parent frame of a point fixed to this frame and expressed in local coordinates.
 
ChVector3< double > PointSpeedLocalToParent (const ChVector3< double > &localpos, const ChVector3< double > &localspeed) const
 Return the velocity in the parent frame of a moving point, given the point location and velocity expressed in local coordinates.
 
ChVector3< double > PointAccelerationLocalToParent (const ChVector3< double > &localpos) const
 Return the acceleration in the parent frame of a point fixed to this frame and expressed in local coordinates. More...
 
ChVector3< double > PointAccelerationLocalToParent (const ChVector3< double > &localpos, const ChVector3< double > &localspeed, const ChVector3< double > &localacc) const
 Return the acceleration in the parent frame of a moving point, given the point location, velocity, and acceleration expressed in local coordinates.
 
ChVector3< double > PointSpeedParentToLocal (const ChVector3< double > &parentpos, const ChVector3< double > &parentspeed) const
 Return the velocity of a point expressed in this frame, given the point location and velocity in the parent frame.
 
ChVector3< double > PointAccelerationParentToLocal (const ChVector3< double > &parentpos, const ChVector3< double > &parentspeed, const ChVector3< double > &parentacc) const
 Return the acceleration of a point expressed in this frame, given the point location, velocity, and acceleration in the parent frame.
 
ChFrameMoving< double > TransformLocalToParent (const ChFrameMoving< double > &F) const
 Transform a moving frame from 'this' local coordinate system to parent frame coordinate system.
 
ChFrameMoving< double > TransformParentToLocal (const ChFrameMoving< double > &F) const
 Transform a moving frame from the parent coordinate system to 'this' local frame coordinate system.
 
bool Equals (const ChFrameMoving< double > &other) const
 Returns true if this transform is identical to the other transform.
 
bool Equals (const ChFrameMoving< double > &other, double tol) const
 Returns true if this transform is equal to the other transform, within a tolerance 'tol'.
 
virtual void Invert () override
 Invert in place. More...
 
ChFrameMoving< double > GetInverse () const
 Return the inverse transform.
 
- Public Member Functions inherited from chrono::ChFrame< double >
 ChFrame (const ChVector3< double > &v=ChVector3< double >(0, 0, 0), const ChQuaternion< double > &q=ChQuaternion< double >(1, 0, 0, 0))
 Default constructor, or construct from pos and rot (as a quaternion)
 
 ChFrame (const ChVector3< double > &v, const ChMatrix33< double > &R)
 Construct from pos and rotation (as a 3x3 matrix)
 
 ChFrame (const ChCoordsys< double > &C)
 Construct from a coordsys.
 
 ChFrame (const ChVector3< double > &v, const double angle, const ChVector3< double > &u)
 Construct from position mv and rotation of angle alpha around unit vector mu.
 
 ChFrame (const ChFrame< double > &other)
 Copy constructor, build from another frame.
 
ChFrame< double > & operator= (const ChFrame< double > &other)
 Assignment operator: copy from another frame.
 
bool operator== (const ChFrame< double > &other) const
 Returns true for identical frames.
 
bool operator!= (const ChFrame< double > &other) const
 Returns true for different frames.
 
ChFrame< double > operator* (const ChFrame< double > &F) const
 Transform another frame through this frame. More...
 
ChVector3< double > operator* (const ChVector3< double > &v) const
 Transform a vector through this frame (express in parent frame). More...
 
ChFrame< double > operator>> (const ChFrame< double > &F) const
 Transform another frame through this frame. More...
 
ChVector3< double > operator/ (const ChVector3< double > &v) const
 Transform a vector through this frame (express from parent frame). More...
 
ChFrame< double > & operator>>= (const ChFrame< double > &F)
 Transform this frame by pre-multiplication with another frame. More...
 
ChFrame< double > & operator>>= (const ChVector3< double > &v)
 Transform this frame by pre-multiplication with a given vector (translate frame).
 
ChFrame< double > & operator>>= (const ChQuaternion< double > &q)
 Transform this frame by pre-multiplication with a given quaternion (rotate frame).
 
ChFrame< double > & operator>>= (const ChCoordsys< double > &C)
 Transform this frame by pre-multiplication with a given coordinate system.
 
ChFrame< double > & operator*= (const ChFrame< double > &F)
 Transform this frame by post-multiplication with another frame. More...
 
ChCoordsys< double > & GetCoordsys ()
 Return both current rotation and translation as a ChCoordsys object.
 
const ChCoordsys< double > & GetCoordsys () const
 
ChVector3< double > & GetPos ()
 Return the current translation as a 3d vector.
 
const ChVector3< double > & GetPos () const
 
ChQuaternion< double > & GetRot ()
 Return the current rotation as a quaternion.
 
const ChQuaternion< double > & GetRot () const
 
ChMatrix33< double > & GetRotMat ()
 Return the current rotation as a 3x3 matrix.
 
const ChMatrix33< double > & GetRotMat () const
 
ChVector3< double > GetRotAxis ()
 Get axis of finite rotation, in parent space.
 
double GetRotAngle ()
 Get angle of rotation about axis of finite rotation.
 
void SetCoordsys (const ChCoordsys< double > &C)
 Impose both translation and rotation as a single ChCoordsys. More...
 
void SetCoordsys (const ChVector3< double > &v, const ChQuaternion< double > &q)
 Impose both translation and rotation. More...
 
void SetRot (const ChQuaternion< double > &q)
 Impose the rotation as a quaternion. More...
 
void SetRot (const ChMatrix33< double > &R)
 Impose the rotation as a 3x3 matrix. More...
 
void SetPos (const ChVector3< double > &mpos)
 Impose the translation.
 
void ConcatenatePreTransformation (const ChFrame< double > &F)
 Apply a transformation (rotation and translation) represented by another frame. More...
 
void ConcatenatePostTransformation (const ChFrame< double > &F)
 Apply a transformation (rotation and translation) represented by another frame F in local coordinate. More...
 
void Move (const ChVector3< double > &v)
 An easy way to move the frame by the amount specified by vector v, (assuming v expressed in parent coordinates)
 
void Move (const ChCoordsys< double > &C)
 Apply both translation and rotation, assuming both expressed in parent coordinates, as a vector for translation and quaternion for rotation,.
 
ChVector3< double > TransformPointLocalToParent (const ChVector3< double > &v) const
 Transform a point from the local frame coordinate system to the parent coordinate system.
 
ChVector3< double > TransformPointParentToLocal (const ChVector3< double > &v) const
 Transforms a point from the parent coordinate system to local frame coordinate system.
 
ChVector3< double > TransformDirectionLocalToParent (const ChVector3< double > &d) const
 Transform a direction from the parent frame coordinate system to 'this' local coordinate system.
 
ChVector3< double > TransformDirectionParentToLocal (const ChVector3< double > &d) const
 Transforms a direction from 'this' local coordinate system to parent frame coordinate system.
 
ChWrench< double > TransformWrenchLocalToParent (const ChWrench< double > &w) const
 Transform a wrench from the local coordinate system to the parent coordinate system.
 
ChWrench< double > TransformWrenchParentToLocal (const ChWrench< double > &w) const
 Transform a wrench from the parent coordinate system to the local coordinate system.
 
ChFrame< double > TransformLocalToParent (const ChFrame< double > &F) const
 Transform a frame from 'this' local coordinate system to parent frame coordinate system.
 
ChFrame< double > TransformParentToLocal (const ChFrame< double > &F) const
 Transform a frame from the parent coordinate system to 'this' local frame coordinate system.
 
bool Equals (const ChFrame< double > &other) const
 Returns true if this transform is identical to the other transform.
 
bool Equals (const ChFrame< double > &other, double tol) const
 Returns true if this transform is equal to the other transform, within a tolerance 'tol'.
 
void Normalize ()
 Normalize the rotation, so that quaternion has unit length.
 
virtual void SetIdentity ()
 Sets to no translation and no rotation.
 
ChFrame< double > GetInverse () const
 Return the inverse transform.
 
- Public Member Functions inherited from chrono::ChLoadableUVW
virtual bool IsTetrahedronIntegrationNeeded ()
 If true, use quadrature over u,v,w in [0..1] range as tetrahedron volumetric coords (with z=1-u-v-w) otherwise use default quadrature over u,v,w in [-1..+1] as box isoparametric coords.
 
virtual bool IsTrianglePrismIntegrationNeeded ()
 If true, use quadrature over u,v in [0..1] range as triangle natural coords (with z=1-u-v), and use linear quadrature over w in [-1..+1], otherwise use default quadrature over u,v,w in [-1..+1] as box isoparametric coords.
 

Protected Attributes

std::vector< std::shared_ptr< ChMarker > > marklist
 list of markers
 
std::vector< std::shared_ptr< ChForce > > forcelist
 list of forces
 
ChVector3d gyro
 gyroscopic torque, i.e. Qm = Wvel x (XInertia*Wvel)
 
ChVector3d Xforce
 force acting on body, applied to COM (in absolute coords)
 
ChVector3d Xtorque
 torque acting on body (in body local coords)
 
ChVector3d Force_acc
 force accumulator, applied to COM (in absolute coords)
 
ChVector3d Torque_acc
 torque accumulator (in body local coords)
 
ChVariablesBodyOwnMass variables
 interface to solver (store inertia and coordinates)
 
float max_speed
 limit on linear speed
 
float max_wvel
 limit on angular velocity
 
float sleep_time
 
float sleep_minspeed
 
float sleep_minwvel
 
float sleep_starttime
 
unsigned int index
 unique sequential body identifier, used for indexing (internal use only)
 
- Protected Attributes inherited from chrono::ChPhysicsItem
ChSystemsystem
 parent system
 
std::shared_ptr< ChVisualModelInstancevis_model_instance
 instantiated visualization model
 
std::vector< std::shared_ptr< ChCamera > > cameras
 set of cameras
 
unsigned int offset_x
 offset in vector of state (position part)
 
unsigned int offset_w
 offset in vector of state (speed part)
 
unsigned int offset_L
 offset in vector of lagrangian multipliers
 
- Protected Attributes inherited from chrono::ChObj
double ChTime
 object simulation time
 
std::string m_name
 object name
 
int m_identifier
 object unique identifier
 
int m_tag
 user-supplied tag
 
- Protected Attributes inherited from chrono::ChFrameMoving< double >
ChCoordsys< double > m_csys_dt
 rotation and position velocity, as vector + quaternion
 
ChCoordsys< double > m_csys_dtdt
 rotation and position acceleration, as vector + quaternion
 
- Protected Attributes inherited from chrono::ChFrame< double >
ChCoordsys< double > m_csys
 position and rotation, as vector + quaternion
 
ChMatrix33< double > m_rmat
 3x3 orthogonal rotation matrix
 

Friends

class ChSystem
 
class ChSystemMulticore
 
class ChSystemMulticoreNSC
 
class ChAssembly
 
class modal::ChModalAssembly
 
class ChConveyor
 

Additional Inherited Members

- Protected Member Functions inherited from chrono::ChObj
int GenerateUniqueIdentifier ()
 

Member Function Documentation

◆ AccumulateForce()

void chrono::ChBody::AccumulateForce ( const ChVector3d force,
const ChVector3d appl_point,
bool  local 
)

Add an applied force to the body's accumulator (as an increment).

It is the caller's responsibility to clear the force and torque accumulators at each integration step. If local = true, the provided applied force is assumed to be expressed in body coordinates. If local = false, the provided applied force is assumed to be expressed in absolute coordinates.

Parameters
forceapplied force
appl_pointapplication point
localforce and point expressed in body local frame?

◆ AccumulateTorque()

void chrono::ChBody::AccumulateTorque ( const ChVector3d torque,
bool  local 
)

Add an applied torque to the body's accumulator (as an increment).

It is the caller's responsibility to clear the force and torque accumulators at each integration step. If local = true, the provided applied torque is assumed to be expressed in body coordinates. If local = false, the provided applied torque is assumed to be expressed in absolute coordinates.

Parameters
torqueapplied torque
localtorque expressed in body local frame?

◆ ArchiveIn()

void chrono::ChBody::ArchiveIn ( ChArchiveIn archive_in)
overridevirtual

Method to allow deserialization of transient data from archives.

Method to allow de serialization of transient data from archives.

< pointer to the collision model

Reimplemented from chrono::ChBodyFrame.

Reimplemented in chrono::ChBodyAuxRef.

◆ ClampSpeed()

void chrono::ChBody::ClampSpeed ( )

Clamp the body speed to the provided limits.

When this function is called, the speed of the body is clamped to the range specified by max_speed and max_wvel. Remember to put the body in the SetLimitSpeed(true) mode.

◆ ComputeGyro()

void chrono::ChBody::ComputeGyro ( )

Computes the gyroscopic torque.

In fact, in sake of highest speed, the gyroscopic torque isn't automatically updated each time a SetCoordsys() or SetCoordsysDt() etc. is called, but only if necessary, for each UpdateState().

◆ ComputeNF()

void chrono::ChBody::ComputeNF ( const double  U,
const double  V,
const double  W,
ChVectorDynamic<> &  Qi,
double &  detJ,
const ChVectorDynamic<> &  F,
ChVectorDynamic<> *  state_x,
ChVectorDynamic<> *  state_w 
)
overridevirtual

Evaluate Q=N'*F, for Q generalized lagrangian load, where N is some type of matrix evaluated at point P(U,V,W) assumed in absolute coordinates, and F is a load assumed in absolute coordinates.

det[J] is unused.

Parameters
Ux coordinate of application point in absolute space
Vy coordinate of application point in absolute space
Wz coordinate of application point in absolute space
QiReturn result of N'*F here, maybe with offset block_offset
detJReturn det[J] here
FInput F vector, size is 6, it is {Force,Torque} in absolute coords.
state_xif != 0, update state (pos. part) to this, then evaluate Q
state_wif != 0, update state (speed part) to this, then evaluate Q

Implements chrono::ChLoadableUVW.

◆ GetAccumulatedForce()

const ChVector3d& chrono::ChBody::GetAccumulatedForce ( ) const
inline

Return the current value of the accumulator force.

Note that this is a resultant force as applied to the COM and expressed in the absolute frame.

◆ GetAccumulatedTorque()

const ChVector3d& chrono::ChBody::GetAccumulatedTorque ( ) const
inline

Return the current value of the accumulator torque.

Note that this is a resultant torque expressed in the body local frame.

◆ GetAppliedForce()

ChVector3d chrono::ChBody::GetAppliedForce ( )

Return the resultant applied force on the body.

This resultant force includes all external applied loads acting on this body (from gravity, loads, springs, etc). However, this does not include any constraint forces. In particular, contact forces are not included if using the NSC formulation, but are included when using the SMC formulation.

◆ GetAppliedTorque()

ChVector3d chrono::ChBody::GetAppliedTorque ( )

Return the resultant applied torque on the body.

This resultant torque includes all external applied loads acting on this body (from gravity, loads, springs, etc). However, this does not include any constraint forces. In particular, contact torques are not included if using the NSC formulation, but are included when using the SMC formulation.

◆ GetForces()

const std::vector<std::shared_ptr<ChForce> >& chrono::ChBody::GetForces ( ) const
inline

Gets the list of children forces.

NOTE: to modify this list, use the appropriate Remove.. and Add.. functions.

◆ GetFrameCOMToAbs()

virtual const ChFrameMoving& chrono::ChBody::GetFrameCOMToAbs ( ) const
inlinevirtual

Get the rigid body coordinate system that represents the GOG (Center of Gravity).

The mass and inertia tensor are defined with respect to this coordinate system, which is also assumed to be the default coordinates of the body. By default, a call to body.GetPos() is equivalent to body.GetFrame_COG_abs().GetPos().

◆ GetFrameRefToAbs()

virtual const ChFrameMoving& chrono::ChBody::GetFrameRefToAbs ( ) const
inlinevirtual

Get the rigid body coordinate system that is used for defining the collision shapes and the ChMarker objects.

For the base ChBody, this is always the same reference of the COG.

Reimplemented in chrono::ChBodyAuxRef.

◆ GetInertia()

const ChMatrix33& chrono::ChBody::GetInertia ( ) const
inline

Get the inertia tensor, expressed in the local coordinate system.

The return 3x3 symmetric matrix contains the following values:

 [ int{y^2+z^2}dm    -int{xy}dm    -int{xz}dm    ]
 [                  int{x^2+z^2}   -int{yz}dm    ]
 [                                int{x^2+y^2}dm ]

◆ GetInertiaXX()

ChVector3d chrono::ChBody::GetInertiaXX ( ) const

Get the diagonal part of the inertia tensor (Ixx, Iyy, Izz values).

The return 3x1 vector contains the following values:

[  int{y^2+z^2}dm   int{x^2+z^2}   int{x^2+y^2}dm ]

◆ GetInertiaXY()

ChVector3d chrono::ChBody::GetInertiaXY ( ) const

Get the extra-diagonal part of the inertia tensor (Ixy, Ixz, Iyz values).

The return 3x1 vector contains the following values:

[ -int{xy}dm   -int{xz}dm   -int{yz}dm ]

◆ GetMarkers()

const std::vector<std::shared_ptr<ChMarker> >& chrono::ChBody::GetMarkers ( ) const
inline

Gets the list of children markers.

NOTE: to modify this list, use the appropriate Remove.. and Add.. functions.

◆ GetTotalAABB()

ChAABB chrono::ChBody::GetTotalAABB ( )
overridevirtual

Get the axis-aligned bounding (AABB) box of the object.

The body AABB is the AABB of its collision model (if any).

Reimplemented from chrono::ChPhysicsItem.

◆ GetVisualModelFrame()

virtual ChFrame chrono::ChBody::GetVisualModelFrame ( unsigned int  nclone = 0)
inlineoverridevirtual

Get the reference frame (expressed in and relative to the absolute frame) of the visual model.

For a ChBody, this is the main coordinate system of the rigid body.

Reimplemented from chrono::ChPhysicsItem.

◆ IsActive()

bool chrono::ChBody::IsActive ( ) const
overridevirtual

Return true if the body is currently active and therefore included into the system solver.

A body is inactive if it is fixed to ground or in sleep mode.

Reimplemented from chrono::ChPhysicsItem.

◆ RemoveAllForces()

void chrono::ChBody::RemoveAllForces ( )

Remove all markers at once.

Faster than doing multiple RemoveForce().

◆ RemoveAllMarkers()

void chrono::ChBody::RemoveAllMarkers ( )

Remove all markers at once.

Faster than doing multiple RemoveForce().

◆ RemoveForce()

void chrono::ChBody::RemoveForce ( std::shared_ptr< ChForce aforce)

Remove a specific force from this body.

Warning: linear time search.

◆ RemoveMarker()

void chrono::ChBody::RemoveMarker ( std::shared_ptr< ChMarker amarker)

Remove a specific marker from this body.

Warning: linear time search.

◆ SetFixed()

void chrono::ChBody::SetFixed ( bool  state)

Sets the 'fixed' state of the body.

If true, the body does not move with respect to the absolute reference frame. Its state is also removed by the system, thus reducing the global size of the system. If this is not desired, use ChLinkMateFix or ChLinkLockLock instead.

◆ SetInertia()

void chrono::ChBody::SetInertia ( const ChMatrix33<> &  newXInertia)

Set the inertia tensor of the body.

The provided 3x3 matrix should be symmetric and contain the inertia tensor, expressed in the local coordinate system:

              [ int{y^2+z^2}dm    -int{xy}dm    -int{xz}dm    ]
newXInertia = [                  int{x^2+z^2}   -int{yz}dm    ]
              [                                int{x^2+y^2}dm ]

◆ SetInertiaXX()

void chrono::ChBody::SetInertiaXX ( const ChVector3d iner)

Set the diagonal part of the inertia tensor (Ixx, Iyy, Izz values).

The provided 3x1 vector should contain the moments of inertia, expressed in the local coordinate frame:

iner = [  int{y^2+z^2}dm   int{x^2+z^2}   int{x^2+y^2}dm ]

◆ SetInertiaXY()

void chrono::ChBody::SetInertiaXY ( const ChVector3d iner)

Set the off-diagonal part of the inertia tensor (Ixy, Ixz, Iyz values).

The provided 3x1 vector should contain the products of inertia, expressed in the local coordinate frame:

iner = [ -int{xy}dm   -int{xz}dm   -int{yz}dm ]

◆ SetMass()

void chrono::ChBody::SetMass ( double  newmass)
inline

Set the body mass.

Try not to mix bodies with too high/too low values of mass, for numerical stability.

◆ SetMaxAngVel()

void chrono::ChBody::SetMaxAngVel ( float  m_max_wvel)
inline

Set the maximum angular speed (beyond this limit it will be clamped).

This speed limit is active only if you set SetLimitSpeed(true);

◆ SetMaxLinVel()

void chrono::ChBody::SetMaxLinVel ( float  m_max_speed)
inline

Set the maximum linear speed (beyond this limit it will be clamped).

This speed limit is active only if you set SetLimitSpeed(true);

◆ SetSleeping()

void chrono::ChBody::SetSleeping ( bool  state)

Force the body in sleeping mode or not.

Usually this state change is handled internally.

◆ SetSleepingAllowed()

void chrono::ChBody::SetSleepingAllowed ( bool  state)

Enable/disable option for setting bodies to 'sleep'.

If the sleeping is allowed, bodies which stay in same place for long enough time will be deactivated, for optimization. By default the sleeping is enabled.

◆ SetUseGyroTorque()

void chrono::ChBody::SetUseGyroTorque ( bool  state)

Enable/disable the gyroscopic torque (quadratic term).

This is useful in virtual reality and real-time simulations, where objects that spin too fast with non-uniform inertia tensors (e.g., thin cylinders) might cause the integration to diverge quickly. The realism is limited, but the simulation is more stable. By default the gyroscopic torque is enabled.

◆ TrySleeping()

bool chrono::ChBody::TrySleeping ( )

Test if a body could go in sleeping state if requirements are satisfied.

Return true if state could be changed from no sleep to sleep.

◆ Variables()

virtual ChVariables& chrono::ChBody::Variables ( )
inlineoverridevirtual

Return a reference to the encapsulated ChVariablesBody, representing states (pos, speed, or accel.) and forces.

The ChVariablesBodyOwnMass is the interface to the system solver.

Implements chrono::ChBodyFrame.


The documentation for this class was generated from the following files:
  • /builds/uwsbel/chrono/src/chrono/physics/ChBody.h
  • /builds/uwsbel/chrono/src/chrono/physics/ChBody.cpp