Description

Base class for a terrain node.

Implements required functionality for a co-simulation node (Initialize(), Synchronize(), Advance()) and all MPI communication.

A derived class must implement functions to:

specify the communication interface type (SupportsMeshInterface())
construct and initialize the concrete terrain object (OnInitialize())
accept new spindle body states (UpdateWheelProxy() and/or UpdateMeshProxies())
provide terrain forces acting on the spindle bodies (GetForceWheelProxy() and/or GetForcesMeshProxies())
advance the dynamic state of the terrain (OnAdvance())

Optionally, a derived class may implement functions to:

perform additional operations after a synchronization data exchange (OnSynchronize())
perform additional data output (OnOutputData())
provide run-time visualization (Render())

#include <ChVehicleCosimTerrainNode.h>

Inheritance diagram for chrono::vehicle::ChVehicleCosimTerrainNode:

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Collaboration diagram for chrono::vehicle::ChVehicleCosimTerrainNode:

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Public Member Functions
virtual NodeType	GetNodeType () const override
	Return the node type as NodeType::TERRAIN.

void	EnableRuntimeVisualization (bool render, double render_fps=100)
	Enable/disable run-time visualization (default: false). More...

void	SetDimensions (double length, double width)
	Set the terrain patch dimensions. More...

virtual void	Initialize () override final
	Initialize this node. More...

virtual void	Synchronize (int step_number, double time) override final
	Synchronize this node. More...

virtual void	Advance (double step_size) override final
	Advance simulation. More...

virtual void	OutputData (int frame) override final
	Output logging and debugging data.

virtual void	OutputVisualizationData (int frame) override
	Output post-processing visualization data. More...

virtual int	GetNumContacts () const
	Return current number of contacts. More...

Public Member Functions inherited from chrono::vehicle::ChVehicleCosimBaseNode
std::string	GetNodeTypeString () const
	Return the node type as a string.

bool	IsCosimNode () const
	Return true if this node is part of the co-simulation infrastructure.

void	SetStepSize (double step)
	Set the integration step size (default: 1e-4).

double	GetStepSize () const
	Get the integration step size.

void	SetOutDir (const std::string &dir_name, const std::string &suffix)
	Set the name of the output directory and an identifying suffix. More...

void	SetVerbose (bool verbose)
	Enable/disable verbose messages during simulation (default: true).

const std::string &	GetOutDirName () const
	Get the output directory name for this node.

double	GetStepExecutionTime () const
	Get the simulation execution time for the current step on this node. More...

double	GetTotalExecutionTime () const
	Get the cumulative simulation execution time on this node.

virtual void	WriteCheckpoint (const std::string &filename) const
	Write checkpoint to the specified file (which will be created in the output directory).

Protected Member Functions
	ChVehicleCosimTerrainNode (double length, double width)
	Construct a terrain node to wrap a terrain patch of given length and width.

virtual bool	SupportsMeshInterface () const =0
	Specify whether or not the terrain node supports the MESH communication interface. More...

virtual double	GetInitHeight () const =0
	Return the terrain initial height. More...

virtual void	OnInitialize (unsigned int num_tires)=0
	Perform any additional operations after the initial data exchange with the MBS node, including creating any required proxies for the specified number of tires. More...

virtual void	OnSynchronize (int step_number, double time)
	Perform any additional operations after the data exchange and synchronization with the MBS node. More...

virtual void	OnAdvance (double step_size)=0
	Advance the state of the terrain system by the specified step.

virtual void	OnOutputData (int frame)
	Perform additional output at the specified frame (called from within OutputData).

virtual void	Render (double time)
	Render simulation. More...

virtual void	UpdateMeshProxies (unsigned int i, MeshState &mesh_state)
	Update the state of all proxy bodies for the i-th tire mesh. More...

virtual void	GetForcesMeshProxies (unsigned int i, MeshContact &mesh_contact)
	Collect cumulative contact forces on all proxy bodies for the i-th tire mesh. More...

virtual void	UpdateWheelProxy (unsigned int i, BodyState &spindle_state)=0
	Update the state of the wheel proxy body for the i-th tire. More...

virtual void	GetForceWheelProxy (unsigned int i, TerrainForce &wheel_contact)=0
	Collect cumulative contact force and torque on the wheel proxy body for the i-th tire. More...

Protected Member Functions inherited from chrono::vehicle::ChVehicleCosimBaseNode
	ChVehicleCosimBaseNode (const std::string &name)

Protected Attributes
bool	m_render
	if true, perform run-time rendering

double	m_render_step
	time step between rendered frames

double	m_hdimX
	patch half-length (X direction)

double	m_hdimY
	patch half-width (Y direction)

InterfaceType	m_interface_type
	type of communication interface

std::vector< double >	m_tire_radius
	tire radius

std::vector< double >	m_tire_width
	tire width

std::vector< double >	m_load_mass
	vertical load on tire

std::vector< MaterialInfo >	m_mat_props
	tire contact material properties

std::vector< MeshData >	m_mesh_data
	tire mesh data

std::vector< MeshState >	m_mesh_state
	tire mesh state (used for MESH communication)

std::vector< BodyState >	m_spindle_state
	spindle state (used for BODY communication interface)

Protected Attributes inherited from chrono::vehicle::ChVehicleCosimBaseNode
int	m_rank
	MPI rank of this node (in MPI_COMM_WORLD)

double	m_step_size
	integration step size

std::string	m_name
	name of the node

std::string	m_out_dir
	top-level output directory

std::string	m_node_out_dir
	node-specific output directory

std::ofstream	m_outf
	output file stream

unsigned int	m_num_mbs_nodes

unsigned int	m_num_terrain_nodes

unsigned int	m_num_tire_nodes

ChTimer< double >	m_timer
	timer for integration cost

double	m_cum_sim_time
	cumulative integration cost

bool	m_verbose
	verbose messages during simulation?

Additional Inherited Members
Public Types inherited from chrono::vehicle::ChVehicleCosimBaseNode
enum	NodeType { NodeType::MBS, NodeType::TERRAIN, NodeType::TIRE }
	Type of node participating in co-simulation. More...

enum	InterfaceType { InterfaceType::BODY, InterfaceType::MESH }
	Type of the tire-terrain communication interface. More...

Static Public Member Functions inherited from chrono::vehicle::ChVehicleCosimBaseNode
static std::string	OutputFilename (const std::string &dir, const std::string &root, const std::string &ext, int frame, int frame_digits)
	Utility function for creating an output file name. More...

Static Protected Attributes inherited from chrono::vehicle::ChVehicleCosimBaseNode
static const double	m_gacc = -9.81

Member Function Documentation

◆ Advance()

void chrono::vehicle::ChVehicleCosimTerrainNode::Advance ( double step_size )

finaloverridevirtual

Advance simulation.

This function is called after a synchronization to allow the node to advance its state by the specified time step. A node is allowed to take as many internal integration steps as required, but no inter-node communication should occur.

Implements chrono::vehicle::ChVehicleCosimBaseNode.

◆ EnableRuntimeVisualization()

void chrono::vehicle::ChVehicleCosimTerrainNode::EnableRuntimeVisualization	(	bool	render,
		double	render_fps = `100`
	)

Enable/disable run-time visualization (default: false).

If enabled, rendering is done with the specified frequency. Note that a particular concrete terrain node may not support run-time visualization or may not render all physics elements.

◆ GetForcesMeshProxies()

virtual void chrono::vehicle::ChVehicleCosimTerrainNode::GetForcesMeshProxies	(	unsigned int	i,
		MeshContact &	mesh_contact
	)

inlineprotectedvirtual

Collect cumulative contact forces on all proxy bodies for the i-th tire mesh.

Load indices of vertices in contact and the corresponding vertex forces (expressed in absolute frame) into the provided MeshContact struct.

◆ GetForceWheelProxy()

virtual void chrono::vehicle::ChVehicleCosimTerrainNode::GetForceWheelProxy	(	unsigned int	i,
		TerrainForce &	wheel_contact
	)

protectedpure virtual

Collect cumulative contact force and torque on the wheel proxy body for the i-th tire.

Load contact forces (expressed in absolute frame) into the provided TerrainForce struct.

◆ GetInitHeight()

virtual double chrono::vehicle::ChVehicleCosimTerrainNode::GetInitHeight ( ) const

protectedpure virtual

Return the terrain initial height.

This value must be available before the call to Initialize() (and therefore, before the derived class's OnInitialize() is called).

Implemented in chrono::vehicle::ChVehicleCosimTerrainNodeChrono.

◆ GetNumContacts()

virtual int chrono::vehicle::ChVehicleCosimTerrainNode::GetNumContacts ( ) const

inlinevirtual

Return current number of contacts.

(concrete terrain specific)

◆ Initialize()

void chrono::vehicle::ChVehicleCosimTerrainNode::Initialize ( )

finaloverridevirtual

Initialize this node.

This function allows the node to initialize itself and, optionally, perform an initial data exchange with any other node.

Reimplemented from chrono::vehicle::ChVehicleCosimBaseNode.

◆ OnInitialize()

virtual void chrono::vehicle::ChVehicleCosimTerrainNode::OnInitialize ( unsigned int num_tires )

protectedpure virtual

Perform any additional operations after the initial data exchange with the MBS node, including creating any required proxies for the specified number of tires.

A derived class has access to the following vectors (of size equal to the number of tires):

radius for each tire (through m_tire_radius)
width for each tire (through m_tire_width)
mesh information for each tire (through m_mesh_data)
contact material for each tire (through m_mat_props)
vertical load on each tire (through m_load_mass)

Implemented in chrono::vehicle::ChVehicleCosimTerrainNodeChrono, and chrono::vehicle::ChVehicleCosimTerrainNodeGranularSPH.

◆ OnSynchronize()

virtual void chrono::vehicle::ChVehicleCosimTerrainNode::OnSynchronize	(	int	step_number,
		double	time
	)

inlineprotectedvirtual

Perform any additional operations after the data exchange and synchronization with the MBS node.

A derived class has access to the following vectors (of size equal to the number of tires):

full dynamic state of the spindle bodies (through m_spindle_state) when using the BODY communication interface
state of the mesh vertices (through m_mesh_state) when using the MESH communication interface

◆ OutputVisualizationData()

virtual void chrono::vehicle::ChVehicleCosimTerrainNode::OutputVisualizationData ( int frame )

inlineoverridevirtual

Output post-processing visualization data.

If implemented, this function should write a file in the "visualization" subdirectory of m_node_out_dir.

Implements chrono::vehicle::ChVehicleCosimBaseNode.

Reimplemented in chrono::vehicle::ChVehicleCosimTerrainNodeGranularOMP, chrono::vehicle::ChVehicleCosimTerrainNodeGranularGPU, chrono::vehicle::ChVehicleCosimTerrainNodeRigid, and chrono::vehicle::ChVehicleCosimTerrainNodeGranularSPH.

◆ Render()

virtual void chrono::vehicle::ChVehicleCosimTerrainNode::Render ( double time )

inlineprotectedvirtual

Render simulation.

This function is called from Advance() at the frequency spoecified in the call to EnableRuntimeVisualization(). Any call to Render occurs after a call to OnAdvance().

◆ SetDimensions()

void chrono::vehicle::ChVehicleCosimTerrainNode::SetDimensions	(	double	length,
		double	width
	)

Set the terrain patch dimensions.

If invoked, this function must be called before Initialize.

◆ SupportsMeshInterface()

virtual bool chrono::vehicle::ChVehicleCosimTerrainNode::SupportsMeshInterface ( ) const

protectedpure virtual

Specify whether or not the terrain node supports the MESH communication interface.

See ChVehicleCosimBaseNode::InterfaceType. A terrain that also supports the MESH communication interface must override the functions UpdateMeshProxies() and GetForcesMeshProxies().

◆ Synchronize()

void chrono::vehicle::ChVehicleCosimTerrainNode::Synchronize	(	int	step_number,
		double	time
	)

finaloverridevirtual

Synchronize this node.

This function is called at every co-simulation synchronization time to allow the node to exchange information with any other node.

Implements chrono::vehicle::ChVehicleCosimBaseNode.

◆ UpdateMeshProxies()

virtual void chrono::vehicle::ChVehicleCosimTerrainNode::UpdateMeshProxies	(	unsigned int	i,
		MeshState &	mesh_state
	)

inlineprotectedvirtual

Update the state of all proxy bodies for the i-th tire mesh.

Use information in the provided MeshState struct (vertex positions and velocities expressed in absolute frame).

◆ UpdateWheelProxy()

virtual void chrono::vehicle::ChVehicleCosimTerrainNode::UpdateWheelProxy	(	unsigned int	i,
		BodyState &	spindle_state
	)

protectedpure virtual

Update the state of the wheel proxy body for the i-th tire.

Use information in the provided BodyState struct (pose and velocities expressed in absolute frame).

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

/builds/uwsbel/chrono/src/chrono_vehicle/cosim/ChVehicleCosimTerrainNode.h
/builds/uwsbel/chrono/src/chrono_vehicle/cosim/ChVehicleCosimTerrainNode.cpp

Description

Public Member Functions

Protected Member Functions

Protected Attributes

Additional Inherited Members

Member Function Documentation

◆ Advance()

◆ EnableRuntimeVisualization()

◆ GetForcesMeshProxies()

◆ GetForceWheelProxy()

◆ GetInitHeight()

◆ GetNumContacts()

◆ Initialize()

◆ OnInitialize()

◆ OnSynchronize()

◆ OutputVisualizationData()

◆ Render()

◆ SetDimensions()

◆ SupportsMeshInterface()

◆ Synchronize()

◆ UpdateMeshProxies()

◆ UpdateWheelProxy()