Functions

Inclined plane with a rigid body.

These functions create an inclined plane A and possibly a uniform-density rigid body B with user-defined geometry and surface friction properties and adds them to an existing plant.

The inclined plane can be modeled as an infinite half-space or as a box with user-defined dimensions. The inclined plane's top surface is located so that it passes through point Wo (the origin of world W). Right-handed orthonormal vectors Wx, Wy, Wz are fixed in the world W. Similarly, Ax, Ay, Az are fixed in the inclined plane A and Bx, By, Bz are fixed in body B. Wz is directed vertically upward (opposite Earth's gravity). The inclined plane A is oriented by initially setting Ax=Wx, Ay=Wy, Az=Wz, and then subjecting A to a right-handed rotation about Ay=Wy.

Some of these functions also add a rigid body B (e.g., a block or sphere) with user-defined mass.

Parameters

[in]	gravity	The magnitude of Earth's local gravitational acceleration in m/s². Earth's gravity is in the world's -z direction.
[in]	inclined_plane_angle	Inclined plane angle (slope) i.e., angle from Wx to Ax with positive sense Wy (radians).
[in]	inclined_plane_dimensions	Optional box dimensions (meters) in the Ax, Ay, Az directions. If dimensions are given, the inclined plane is modeled as a box, otherwise it is a half-space.
[in]	coefficient_friction_inclined_plane	Coulomb's coefficient of friction for inclined plane A (sliding friction and static friction).
[in]	coefficient_friction_bodyB	Coulomb's coefficient of friction data for body B's surfaces (sliding friction and static friction).
[in]	massB	The mass of body B (kilograms), which must be positive.
[out]	plant	Plant that will contain inclined plane A.

Exceptions

std::exception if plant is nullptr or there is invalid data, e.g., non-negative mass, dimensions, etc.

Precondition: plant must be registered with a scene graph.

void AddInclinedPlaneAndGravityToPlant (double gravity, double inclined_plane_angle, const std::optional< Vector3< double > > &inclined_plane_dimensions, const CoulombFriction< double > &coefficient_friction_inclined_plane, MultibodyPlant< double > *plant)

Creates an inclined plane A and adds it to an existing plant.

void AddInclinedPlaneWithBlockToPlant (double gravity, double inclined_plane_angle, const std::optional< Vector3< double > > &inclined_plane_dimensions, const CoulombFriction< double > &coefficient_friction_inclined_plane, const CoulombFriction< double > &coefficient_friction_bodyB, double massB, const Vector3< double > &block_dimensions, bool is_block_with_4Spheres, MultibodyPlant< double > *plant)

Creates an inclined plane A and a uniform-density block (body B), optionally with 4 spheres welded to it, and adds them to an existing plant.

void AddInclinedPlaneWithSphereToPlant (double gravity, double inclined_plane_angle, const std::optional< Vector3< double > > &inclined_plane_dimensions, const CoulombFriction< double > &coefficient_friction_inclined_plane, const CoulombFriction< double > &coefficient_friction_bodyB, double massB, double radiusB, MultibodyPlant< double > *plant)

Creates an inclined plane A and a uniform-density sphere (body B) and adds them to an existing plant.

Function Documentation

◆ AddInclinedPlaneAndGravityToPlant()

void AddInclinedPlaneAndGravityToPlant	(	double	gravity,
		double	inclined_plane_angle,
		const std::optional< Vector3< double > > &	inclined_plane_dimensions,
		const CoulombFriction< double > &	coefficient_friction_inclined_plane,
		MultibodyPlant< double > *	plant )

Creates an inclined plane A and adds it to an existing plant.

See also: Description of parameters

◆ AddInclinedPlaneWithBlockToPlant()

void AddInclinedPlaneWithBlockToPlant	(	double	gravity,
		double	inclined_plane_angle,
		const std::optional< Vector3< double > > &	inclined_plane_dimensions,
		const CoulombFriction< double > &	coefficient_friction_inclined_plane,
		const CoulombFriction< double > &	coefficient_friction_bodyB,
		double	massB,
		const Vector3< double > &	block_dimensions,
		bool	is_block_with_4Spheres,
		MultibodyPlant< double > *	plant )

Creates an inclined plane A and a uniform-density block (body B), optionally with 4 spheres welded to it, and adds them to an existing plant.

Parameters

[in]	block_dimensions	Dimensions (lengths) of block in the Bx, By, Bz directions (meters). To be valid data, these dimensions must be positive.
[in]	is_block_with_4Spheres	This flag is true if block B's contact with inclined plane A is modeled using 4 identical massless spheres welded to the block B's four "bottom" corners, whereas this flag is falseif block B's contact is modeled with a block (box).

See also: Description of other parameters

◆ AddInclinedPlaneWithSphereToPlant()

void AddInclinedPlaneWithSphereToPlant	(	double	gravity,
		double	inclined_plane_angle,
		const std::optional< Vector3< double > > &	inclined_plane_dimensions,
		const CoulombFriction< double > &	coefficient_friction_inclined_plane,
		const CoulombFriction< double > &	coefficient_friction_bodyB,
		double	massB,
		double	radiusB,
		MultibodyPlant< double > *	plant )

Creates an inclined plane A and a uniform-density sphere (body B) and adds them to an existing plant.

Parameters

[in] radiusB The radius of sphere B (meters), which must be positive.

See also: Description of other parameters

Note: Decorative visual geometry is added to the sphere to facilitate visualizing the sphere's rotation.