parameters_context.yaml

constraints:
    Default values for tolerances if no explicit values are set in the ``JointTrajectory`` message.

gains: |
  Only relevant, if ``open_loop_control`` is not set.

  If ``velocity`` is the only command interface for all joints or an ``effort`` command interface is configured, PID controllers are used for every joint.
  This structure contains the controller gains for every joint with the control law

  .. math:: u = k_{ff} v_d + k_p e + k_i \sum e dt + k_d (v_d - v)

  with the desired velocity :math:`v_d`, the measured velocity :math:`v`, the position error :math:`e` (definition see below),
  the controller period :math:`dt`, and the ``velocity`` or ``effort`` manipulated variable (control variable) :math:`u`, respectively.

  If the joint is of continuous type, the position error :math:`e = normalize(s_d - s)` is normalized between :math:`-\pi, \pi`,
  i.e., the shortest rotation to the target position is the desired motion.
  Otherwise  :math:`e = s_d - s` is used, with the desired position :math:`s_d` and the measured
  position :math:`s` from the state interface.