Inheritance diagram for CBall:

Collaboration diagram for CBall:

Public Member Functions
	CBall (std::string simObjectName, ISimObjectCreator *creator)
	Reads parameters, registers states, input/output ports and shared resources.

void	OdeFcn (const double T, const double const X, double const XDot) const
	Cleans up dynamically allocated memory.

bool	HasJacobians () const override

void	OdeJacobian (double T, const double X, double J, int nStates) override

int	GetJacobianSparsity (int nStates, int rowPtr, int colIdx) override

const double *	ForceOut (const double T, const double *const X)
	Returns the force acting from the balls on the box.

Protected Member Functions
void	CalcForces (const double T, const double *const X) const
	Calculates contact forces between balls and box.

void	ForceInterBall (const double T, const double *const X) const
	Calculates contact forces between the balls.

void	AddWallStiffness (const double T, const double *const X, Eigen::MatrixXd &forceJacobian) const

void	AddInterBallStiffness (const double *const X, Eigen::MatrixXd &forceJacobian) const

void	BoxPlanes (const double T, const double *const X, Eigen::Vector3d norms[6], Eigen::Vector3d planePositions[6]) const

void	LatchPlaneSide (int pl, double s) const
	Fixes m_planeSide[pl] from the signed distance `s` to the wall at the first evaluation.

bool	IsWallContact (int pl, double s, double dL, double radius) const

virtual const double *	Position (const double T, const double *const X)
	Returns the velocity of the balls.

virtual const double *	Velocity (const double T, const double *const X)
	Returns the position of the balls.

int	LocalIndex (int globalStateIndex) const
	The index of the velocity state.

Protected Attributes
int	m_count

double	m_gravity
	Number of balls [#].

double *	m_mass
	The gravity (assumed along z-axis) [kgms^-2].

double *	m_radius
	The masses of the balls. [kg].

double *	m_stiffness
	The radii of the balls. [m].

double	m_boxDim [3]
	The linear stiffnesses of the ball. [N/m].

Eigen::Vector3d	m_norms [6]
	The dimensions of the box Lx, Ly, Lz [m].

int	m_planeSide [6]
	Array of box unit normal vectors [-].

Eigen::VectorXd	m_forces
	Side of the plane, relative normal std::vector (-1: inside, 1: outside, else: undef)

Eigen::VectorXd	m_interForces
	3-DOF force acting on each ball i (col(F_i)) from the box. [N]

ISignalPort *	m_inBoxPos
	3-DOF force acting between each ball i (col(F_i)). [N]

ISignalPort *	m_inBoxRot
	Centroid of the box [m].

int	m_iStatePos
	Orientation of the box, Euler angles, x,y,z [rad].

int	m_iStateVel
	The index of the position state.

double	m_outForce [3]

Constructor & Destructor Documentation

◆ CBall()

CBall::CBall	(	std::string	simObjectName,
		ISimObjectCreator *	creator
	)

This constructor performs all initial setup for a ball SimObject. Reading in parameters, setting up communication interface i.e. output ports, input ports, and states, plus additional 'one time only' resource setup.

Parameters

[in]	simObjectName	-> The name of the simobject. Used primarily by superclass constructor
[in]	creator	-> Retrieve parameters. Register states, ports and shared resources

Member Function Documentation

◆ AddInterBallStiffness()

void CBall::AddInterBallStiffness	(	const double *const	X,
		Eigen::MatrixXd &	forceJacobian
	)		const

protected

Adds d(m_interForces)/d(pos), the contact stiffness between the balls, to forceJacobian.

Each pair in contact, as ForceInterBall tests it, pushes the two balls apart equally.

Parameters

[in]	X	-> model-global states
[in,out]	forceJacobian	-> 3Count by 3Count, rows ball forces, columns ball positions

◆ AddWallStiffness()

void CBall::AddWallStiffness	(	const double	T,
		const double *const	X,
		Eigen::MatrixXd &	forceJacobian
	)		const

protected

Adds d(-m_forces)/d(pos), the contact stiffness of the walls, to forceJacobian.

Uses the same contact test as CalcForces, and latches m_planeSide as it does.

Parameters

[in]	T	-> time
[in]	X	-> model-global states
[in,out]	forceJacobian	-> 3Count by 3Count, rows ball forces, columns ball positions

◆ BoxPlanes()

void CBall::BoxPlanes	(	const double	T,
		const double *const	X,
		Eigen::Vector3d	norms[6],
		Eigen::Vector3d	planePositions[6]
	)		const

protected

Unit outward normals of the six walls and one point on each, from the box ports.

Parameters

[in]	T	-> time
[in]	X	-> model-global states
[out]	norms	-> unit normal of each wall
[out]	planePositions	-> a point in each wall

◆ CalcForces()

void CBall::CalcForces	(	const double	T,
		const double *const	X
	)		const

protected

Updates the forces acting between balls as well as the the forces acting on each plane of the box, from the states it is given, at every call. This function calls ForceInterBall.

Parameters

[in]	T	-> time
[in]	X	-> states

◆ ForceInterBall()

void CBall::ForceInterBall	(	const double	T,
		const double *const	X
	)		const

protected

Updates the forces acting between each ball.

Parameters

[in]	T	-> time
[in]	X	-> states

◆ ForceOut()

const double * CBall::ForceOut	(	const double	T,
		const double *const	X
	)

Returns the net force from the balls on the box. 3-dof.

Parameters

[in]	T	-> time
[in]	X	-> states

Returns: -> 3-dof force array

◆ IsWallContact()

bool CBall::IsWallContact	(	int	pl,
		double	s,
		double	dL,
		double	radius
	)		const

protected

Whether wall pl pushes on a ball at signed distance s and distance dL of radius radius.

A ball on the outside of the wall is always pushed back; one on the inside only when it overlaps the wall.

◆ LocalIndex()

int CBall::LocalIndex ( int globalStateIndex ) const

inlineprotected

Turns a model-global state index into one local to this SimObject.

OdeFcn and the port functions are handed the whole model's state vector, so they use the global indices AddState returned directly. OdeJacobian is handed this object's own slice, whose first element is the first ball's Pos, so every index it uses goes through this function (BASE-0033).

◆ OdeFcn()

void CBall::OdeFcn	(	const double	T,
		const double *const	X,
		double *const	XDot
	)		const

Computes object derivatives as a function of time, states and input ports

Returns state derivatives. Velocity as derivative of position, external-force/mass and gravity as derivative of velocity.

Parameters

[in]	T	-> current simulation time
[in]	X	-> current simulation state
[out]	XDot	-> state derivatives
[in]	IsMajorTimeStep	-> Is this a major time step?

◆ Position()

virtual const double * CBall::Position	(	const double	T,
		const double *const	X
	)

protectedvirtual

Parameters

[in]	T	-> time
[in]	X	-> states

Returns: -> The velocities n*3

◆ Velocity()

virtual const double * CBall::Velocity	(	const double	T,
		const double *const	X
	)

protectedvirtual

Parameters

[in]	T	-> time
[in]	X	-> states

Returns: -> The velocities n*3

The documentation for this class was generated from the following file:

webfhsim/reloadrepos/fhsim_base/src/ballbox/CBall.h

Public Member Functions

Protected Member Functions

Protected Attributes

Constructor & Destructor Documentation

◆ CBall()

Member Function Documentation

◆ AddInterBallStiffness()

◆ AddWallStiffness()

◆ BoxPlanes()

◆ CalcForces()

◆ ForceInterBall()

◆ ForceOut()

◆ IsWallContact()

◆ LocalIndex()

◆ OdeFcn()

◆ Position()

◆ Velocity()