chrono::vehicle::ChVehicleCosimTerrainNodeSCM Class Reference

Description

Definition of the SCM deformable terrain node.

#include <ChVehicleCosimTerrainNodeSCM.h>

Inheritance diagram for chrono::vehicle::ChVehicleCosimTerrainNodeSCM:
Collaboration diagram for chrono::vehicle::ChVehicleCosimTerrainNodeSCM:

Public Member Functions

 ChVehicleCosimTerrainNodeSCM (double length, double width)
 Create an SCM terrain node. Note that no SCM parameters are set.
 
 ChVehicleCosimTerrainNodeSCM (const std::string &specfile)
 Create an SCM terrain node using parameters from the provided JSON specfile.
 
virtual ChSystemGetSystem () override
 Return a pointer to the underlying Chrono system.
 
void SetFromSpecfile (const std::string &specfile)
 Set full terrain specification from JSON specfile.
 
void SetPropertiesSCM (double spacing, double Bekker_Kphi, double Bekker_Kc, double Bekker_n, double Mohr_cohesion, double Mohr_friction, double Janosi_shear, double elastic_K, double damping_R)
 Set the SCM material properties for terrain. More...
 
void SetNumThreads (int num_threads)
 Set the number of OpenMP threads for SCM ray-casting (default: 1).
 
void SetProxyContactRadius (double radius)
 Set sweeping sphere radius for proxy bodies (default 5e-3). More...
 
void SetInputFromCheckpoint (const std::string &filename)
 Initialize SCM terrain from the specified checkpoint file (which must exist in the output directory). More...
 
virtual void WriteCheckpoint (const std::string &filename) const override
 Write checkpoint to the specified file (which will be created in the output directory).
 
- Public Member Functions inherited from chrono::vehicle::ChVehicleCosimTerrainNodeChrono
Type GetType () const
 Return the type of this terrain node.
 
void SetProxyFixed (bool fixed)
 Set the proxy bodies as fixed to ground.
 
virtual double GetInitHeight () const override final
 Return the terrain initial height.
 
void AddRigidObstacle (const RigidObstacle &obstacle)
 Add a rigid obstacle.
 
- Public Member Functions inherited from chrono::vehicle::ChVehicleCosimTerrainNode
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.
 

Additional Inherited Members

- Public Types inherited from chrono::vehicle::ChVehicleCosimTerrainNodeChrono
enum  Type {
  Type::RIGID, Type::SCM, Type::GRANULAR_OMP, Type::GRANULAR_GPU,
  Type::GRANULAR_MPI, Type::GRANULAR_SPH, Type::UNKNOWN
}
 Type of Chrono terrain. More...
 
- 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::ChVehicleCosimTerrainNodeChrono
static std::string GetTypeAsString (Type type)
 Return a string describing the type of this terrain node.
 
static Type GetTypeFromString (const std::string &type)
 Infer the terrain node type from the given string.
 
static bool ReadSpecfile (const std::string &specfile, rapidjson::Document &d)
 Read a JSON specification file for a Chrono terrain node.
 
static Type GetTypeFromSpecfile (const std::string &specfile)
 Get the terrain type from the given JSON specification file.
 
static ChVector2 GetSizeFromSpecfile (const std::string &specfile)
 Get the terrain dimensions (length and width) from the given JSON specification file.
 
- 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...
 
- Protected Types inherited from chrono::vehicle::ChVehicleCosimTerrainNodeChrono
typedef std::vector< ProxyBodyProxies
 
- Protected Member Functions inherited from chrono::vehicle::ChVehicleCosimTerrainNodeChrono
 ChVehicleCosimTerrainNodeChrono (Type type, double length, double width, ChContactMethod method)
 Construct a base class terrain node. More...
 
virtual void OnInitialize (unsigned int num_tires) override
 Initialize this Chrono terrain node. More...
 
virtual void OnAdvance (double step_size) override
 Advance simulation. More...
 
- Protected Member Functions inherited from chrono::vehicle::ChVehicleCosimTerrainNode
 ChVehicleCosimTerrainNode (double length, double width)
 Construct a terrain node to wrap a terrain patch of given length and width.
 
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 UpdateMeshProxies (unsigned int i, MeshState &mesh_state)
 Update the state of all proxy bodies for the i-th tire mesh. More...
 
- Protected Member Functions inherited from chrono::vehicle::ChVehicleCosimBaseNode
 ChVehicleCosimBaseNode (const std::string &name)
 
- Protected Attributes inherited from chrono::vehicle::ChVehicleCosimTerrainNodeChrono
Type m_type
 terrain type
 
ChContactMethod m_method
 contact method (SMC or NSC)
 
std::shared_ptr< ChMaterialSurfacem_material_terrain
 material properties for terrain bodies
 
double m_init_height
 terrain initial height
 
std::vector< Proxies > m_proxies
 proxy bodies for each tire
 
bool m_fixed_proxies
 are proxy bodies fixed to ground?
 
std::vector< RigidObstaclem_obstacles
 list of rigid obstacles
 
- Protected Attributes inherited from chrono::vehicle::ChVehicleCosimTerrainNode
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< MeshDatam_mesh_data
 tire mesh data
 
std::vector< MeshState > m_mesh_state
 tire mesh state (used for MESH communication)
 
std::vector< BodyStatem_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?
 
- Static Protected Attributes inherited from chrono::vehicle::ChVehicleCosimBaseNode
static const double m_gacc = -9.81
 

Member Function Documentation

◆ SetInputFromCheckpoint()

void chrono::vehicle::ChVehicleCosimTerrainNodeSCM::SetInputFromCheckpoint ( const std::string &  filename)

Initialize SCM terrain from the specified checkpoint file (which must exist in the output directory).

By default, a flat rectangular SCM terrain patch is used.

◆ SetPropertiesSCM()

void chrono::vehicle::ChVehicleCosimTerrainNodeSCM::SetPropertiesSCM ( double  spacing,
double  Bekker_Kphi,
double  Bekker_Kc,
double  Bekker_n,
double  Mohr_cohesion,
double  Mohr_friction,
double  Janosi_shear,
double  elastic_K,
double  damping_R 
)

Set the SCM material properties for terrain.

Parameters
spacingSCM grid spacing
Bekker_KphiKphi, frictional modulus in Bekker model
Bekker_KcKc, cohesive modulus in Bekker model
Bekker_nn, exponent of sinkage in Bekker model (usually 0.6...1.8)
Mohr_cohesioncohesion [Pa], for shear failure
Mohr_frictionFriction angle [degrees], for shear failure
Janosi_shearshear parameter J [m], (usually a few mm or cm)
elastic_Kelastic stiffness K per unit area, [Pa/m] (must be larger than Kphi)
damping_Rvertical damping R per unit area [Pa.s/m] (proportional to vertical speed)

◆ SetProxyContactRadius()

void chrono::vehicle::ChVehicleCosimTerrainNodeSCM::SetProxyContactRadius ( double  radius)
inline

Set sweeping sphere radius for proxy bodies (default 5e-3).

This value is used as a "thickness" for collision meshes (a non-zero value can improve robustness of the collision detection algorithm).


The documentation for this class was generated from the following files:
  • /builds/uwsbel/chrono/src/chrono_vehicle/cosim/terrain/ChVehicleCosimTerrainNodeSCM.h
  • /builds/uwsbel/chrono/src/chrono_vehicle/cosim/terrain/ChVehicleCosimTerrainNodeSCM.cpp