Environment API

class br2.environment.Environment(run_tag, rendering_fps=25, time_step=2e-05, final_time=None)

Attributes:

rendering_fpsint

Rendering fps for output videos. (default=25)

time_stepfloat

Simulation timestep. Faster time-step could reduce the simulation walltime, but the simulation may be unstable. (default=2.0e-5)

final_timeOptional[float]

reset(rod_database_path, assembly_config_path, start_time=0.0, **kwargs)

Creates the simulation environment.

Return type:

None

Parameters:

rod_database_pathstr

assembly_config_pathstr

start_timefloat

run(action, duration=None, disable_progress_bar=False, check_nan=False, check_steady_state=None)

Run simulation for a duration given action.

Return type:

Optional[TerminalInfo]

Parameters:

actiondict

Action specified for each rods.

durationOptional[float]

If duration is not specified, run a single step (duration=step_size)

disable_progress_barbool

check_nanbool

If True, check if any Nan is detected in the simulation at the end of the run. (default=False)

check_steady_stateOptional[int]

Check steady state condition at the end of the run. If 1, the velocity steady- state is checked. If 2, dynamic steady-state condition is checked.(default=None)

save_state(directory=None, verbose=False)

Save state parameters of each rod.

Return type:

None

Parameters:

directory: Optional[str]

Directory path name. The path must exist.

load_state(directory='', clear_callback=False, verbose=False)

Load the rod-state. Compatibale with ‘save_state’ method.

If the save-file does not exist, it returns error.

Return type:

None

Parameters:

directoryOptional[str]

Directory path name.

render_video(**kwargs)

Make video 3D rod movement in time.

Return type:

None

save_data(tag=None)

save_data.

Return type:

None

Parameters:

tagOptional[str]

String tag that appends to the file name.

close()

Close the simulator.

Terminal Information

class br2.environment.TerminalInfo(end_status=False)

Attributes:

end_statusbool

Indicate if simulation reached end.

<variable>_nan_statusbool

Indicate if NaN exists in <variable>. Only given when check_nan is True.

<variable>_steady_state_statusbool

Indicate if <variable> is in steady-state. Only given when check_steady_state is given.

max_velocityfloat

Maximum velocity at the end of the run. Only given when check_steady_state=1.

end_status: bool = False

property combined_nan_status: bool

Combined status for if NaN exists. Return true if any NaN status is true.

Notes

If check_nan is not given in simulation, this property does not give correct indication.

property combined_steady_state_status: bool

Combined status for steady state. Return true if all steady-state status is true.

Notes

If check_steady_state is not given in simulation, this property does not give correct indication.

Data Paths

class br2.environment.DataPaths(tag)

Data path collection

Attributes:

tagstr

Simulation tag that will be appended at the end of the result directory.

pathsstr

Parent directory path

simulationstr

Path to save the simulation data for pause/restart purpose.

renderingsstr

Path to save all the rendering videos.

datastr

Path to save data for the post-processing.

tag: str

property paths: str

property simulation: str

property renderings: str

property data: str

initialize()

Initialization step: create missing directories