bam.erob.actuator
=================

.. py:module:: bam.erob.actuator


Classes
-------

.. autoapisummary::

   bam.erob.actuator.ErobActuator


Module Contents
---------------

.. py:class:: ErobActuator(testbench_class: bam.testbench.Testbench, damping=2.0)

   Bases: :py:obj:`bam.actuator.Actuator`


   Abstract base class for all BAM actuator models.

   Subclasses implement the firmware control law and the motor torque equation
   for a specific actuator family.  An actuator is always attached to a
   :class:`~bam.model.Model` via :meth:`~bam.model.Model.set_actuator`, which
   calls :meth:`initialize` to create the motor parameters (``kt``, ``R``, …)
   on the model.

   :param testbench_class: Class used to instantiate the testbench when a log
       is loaded (typically :class:`~bam.testbench.Pendulum`).


   .. py:attribute:: max_amps
      :value: 12.0



   .. py:attribute:: max_volts
      :value: 48.0



   .. py:attribute:: damping
      :value: 2.0



   .. py:method:: initialize()

      Create motor parameters on the attached model.

      Called automatically by :meth:`set_model`. Must create at minimum
      ``self.model.kt`` and ``self.model.R`` as :class:`~bam.parameter.Parameter`
      instances.



   .. py:method:: load_log(log: dict)

      Called when a log is loaded.

      Instantiates the testbench from the log metadata (mass, length, …)
      and updates actuator settings (kp, vin) from the log.

      :param log: Log dict as loaded from a processed JSON file.



   .. py:method:: control_unit() -> str

      Return the physical unit of the control signal (e.g. ``"volts"``, ``"amps"``).



   .. py:method:: compute_control(q_target: float, q: float, dq: float, dt: float) -> float | None

      Compute the control signal from the current state and target.

      :param q_target: Target joint angle [rad].
      :param q: Current joint angle [rad].
      :param dq: Current joint velocity [rad/s].
      :param dt: Timestep [s].
      :returns: Control signal in the unit given by :meth:`control_unit`.



   .. py:method:: compute_torque(control: float | None, torque_enable: bool, q: float, dq: float) -> float

      Compute the motor torque from the control signal and current state.

      :param control: Control signal (volts, amps, or Nm depending on the actuator).
      :param torque_enable: Whether the actuator is powered.
      :param q: Current joint angle [rad].
      :param dq: Current joint velocity [rad/s].
      :returns: Motor torque [Nm].



   .. py:method:: get_extra_inertia() -> float

      Return the actuator's apparent inertia added to the load [kg·m²].