pySimBlocks.blocks.systems.sofa.sofa_controller

class pySimBlocks.blocks.systems.sofa.sofa_controller.SofaPysimBlocksController(name: str = 'SofaControllerGui')

Bases: _SofaController

Base SOFA controller class bridging the SOFA simulation loop and pySimBlocks.

Supports two operating modes:

SOFA_MASTER (SOFA_MASTER=True): SOFA drives the time loop. A project_yaml must be provided. At each pySimBlocks step the controller reads SOFA outputs, runs one pySimBlocks step, and applies the resulting inputs back to SOFA.

pySimBlocks master (SOFA_MASTER=False): pySimBlocks drives the time loop. The controller acts as a pure I/O shell — no model is built or executed internally.

Subclasses must implement set_inputs() and get_outputs().

IS_READY

Set to True by prepare_scene() when the scene is ready to start the control loop.

SOFA_MASTER

If True, SOFA is the time master.

inputs

Dict of input signals written by set_inputs().

outputs

Dict of output signals populated by get_outputs().

dt

SOFA simulation time step in seconds. Set automatically at runtime.

project_yaml

Path to the pySimBlocks YAML project file.

sim

The pySimBlocks Simulator instance, or None.

variables_to_log

List of signal names to log at each step.

node

The SOFA node to which the controller is attached, set automatically at runtime.

step_index

Total number of SOFA animation steps executed.

verbose

If True, print logged variables at each control step.

prepare_scene() → None

Optional hook executed before the pySimBlocks control loop starts.

Override this method to wait for a preparation condition (e.g. a fixed number of warm-up steps or scene stabilization). Set self.IS_READY = True when the scene is ready. The default implementation sets IS_READY immediately.

set_inputs() → None

Apply inputs from pySimBlocks to SOFA components.

Raises:

NotImplementedError – Always — must be implemented by subclasses.

get_outputs() → None

Read state from SOFA components and populate self.outputs.

Must always succeed and return consistent shapes across calls.

Raises:

NotImplementedError – Always — must be implemented by subclasses.

save() → None

Optional hook executed at each control step.

Override to save logs or export custom data. The default implementation does nothing.

get_block(block_name: str)

Return a block from the pySimBlocks model by name.

Parameters:

block_name – Name of the block to retrieve.

Returns:

The block instance with the specified name.

Raises:

RuntimeError – If the simulator is not initialized or if the block is not found in the model.

onAnimateBeginEvent(event) → None

SOFA callback executed before each physical integration step.

When SOFA_MASTER=True, runs the following sequence at each pySimBlocks step:

1. Read SOFA outputs via get_outputs().

2. Push them into the exchange block.

3. Advance pySimBlocks one step.

4. Retrieve controller inputs from the exchange block.

5. Apply them to SOFA via set_inputs().

Parameters:

event – SOFA animation event (unused).