chrono::vehicle::ChVehicleCosimTerrainNodeSCM Class Reference


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 OnInitialize (unsigned int num_objects) override
 Initialize this Chrono terrain node. 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 SetDimensions (double length, double width)
 Set the terrain patch dimensions. More...
void GetDimensions (double &length, double &width)
 Get the terrain patch dimensions.
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 unsigned 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).
void EnableRuntimeVisualization (double render_fps=100, bool save_img=false)
 Enable run-time visualization (default: false). More...
void SetCameraPosition (const ChVector3d &cam_pos, const ChVector3d &cam_target=VNULL)
 Set camera location and target point.
void SetCameraTracking (bool track)
 Enable/disable tracking of objects (default: true).
void EnablePostprocessVisualization (double render_fps=100)
 Enable Blender postprocessing (default: false). More...
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.
void Render (double step_size)
 Render simulation frame. More...

Additional Inherited Members

- Public Types inherited from chrono::vehicle::ChVehicleCosimTerrainNodeChrono
enum  Type {
 Type of Chrono terrain. More...
- Public Types inherited from chrono::vehicle::ChVehicleCosimBaseNode
enum  NodeType { NodeType::MBS_WHEELED, NodeType::MBS_TRACKED, NodeType::TERRAIN, NodeType::TIRE }
 Type of node participating in co-simulation. More...
enum  InterfaceType { InterfaceType::BODY, InterfaceType::MESH }
 Type of the vehicle-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 ChVector2d 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 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 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 UpdateMeshProxy (unsigned int i, MeshState &mesh_state)
 Update the state of the i-th proxy mesh. More...
- Protected Member Functions inherited from chrono::vehicle::ChVehicleCosimBaseNode
 ChVehicleCosimBaseNode (const std::string &name)
void SendGeometry (const ChVehicleGeometry &geom, int dest) const
 Utility function to pack and send a struct with geometry information.
void RecvGeometry (ChVehicleGeometry &geom, int source) const
 Utility function to receive and unpack a struct with geometry information.
void ProgressBar (unsigned int x, unsigned int n, unsigned int w=50)
 Utility function to display a progress bar to the terminal. More...
- Protected Attributes inherited from chrono::vehicle::ChVehicleCosimTerrainNodeChrono
Type m_type
 terrain type
ChContactMethod m_method
 contact method (SMC or NSC)
std::shared_ptr< ChContactMaterialm_material_terrain
 material properties for terrain bodies
double m_init_height
 terrain initial height
std::vector< std::shared_ptr< Proxy > > m_proxies
 proxies for solid objects
bool m_fixed_proxies
 are proxies fixed to ground?
std::vector< RigidObstaclem_obstacles
 list of rigid obstacles
- Protected Attributes inherited from chrono::vehicle::ChVehicleCosimTerrainNode
double m_dimX
 patch length (X direction)
double m_dimY
 patch width (Y direction)
bool m_wheeled
 comm node (true: TIRE nodes, false: tracked MBS node)
InterfaceType m_interface_type
 communication interface (body or mesh)
int m_num_objects
 number of interacting objects
std::vector< ChAABBm_aabb
 AABB of collision models for interacting objects.
std::vector< ChVehicleGeometrym_geometry
 contact geometry and materials for interacting objects
std::vector< double > m_load_mass
 vertical load on interacting objects
std::vector< int > m_obj_map
 mapping from interacting object to shape
std::vector< MeshState > m_mesh_state
 mesh state (used for MESH communication)
std::vector< BodyStatem_rigid_state
 rigid state (used for BODY communication interface)
std::vector< MeshContactm_mesh_contact
 mesh contact forces (used for MESH communication interface)
std::vector< TerrainForcem_rigid_contact
 rigid contact force (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
bool m_renderRT
 if true, perform run-time rendering
bool m_renderRT_all
 if true, render all frames
double m_renderRT_step
 time step between rendered frames
bool m_writeRT
 if true, write images to file
bool m_renderPP
 if true, save data for post-processing
bool m_renderPP_all
 if true, save data at all frames
double m_renderPP_step
 time step between post-processing save frames
bool m_track
 track objects
ChVector3d m_cam_pos
 camera location
ChVector3d m_cam_target
 camera target (lookat) point
unsigned int m_num_wheeled_mbs_nodes
unsigned int m_num_tracked_mbs_nodes
unsigned int m_num_terrain_nodes
unsigned int m_num_tire_nodes
ChTimer 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

◆ OnInitialize()

void chrono::vehicle::ChVehicleCosimTerrainNodeSCM::OnInitialize ( unsigned int  num_objects)

Initialize this Chrono terrain node.

Construct the terrain system and the proxy bodies, then finalize the underlying system.

Reimplemented from chrono::vehicle::ChVehicleCosimTerrainNodeChrono.

◆ 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.

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)

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