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PID Control in Command-based
=================================================

.. note:: For a description of the WPILib PID control features used by these command-based wrappers, see :ref:`docs/software/advanced-controls/controllers/pidcontroller:PID Control in WPILib`.

One of the most common control algorithms used in FRC\ |reg| and FTC\ |reg| is the :term:`PID` controller. WPILib offers its own :ref:`PIDController <docs/software/advanced-controls/controllers/pidcontroller:PID Control in WPILib>` class to help teams implement this functionality on their robots. The following example is from the RapidReactCommandBot example project ([Java](https://github.com/wpilibsuite/allwpilib/tree/v2027.0.0-alpha-6/wpilibjExamples/src/main/java/org/wpilib/examples/rapidreactcommandbot), [C++](https://github.com/wpilibsuite/allwpilib/tree/v2027.0.0-alpha-6/wpilibcExamples/src/main/cpp/examples/RapidReactCommandBot)) and shows how PIDControllers can be used within the command-based framework:

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A ``PIDController`` is declared inside the ``Shooter`` subsystem. It is used by ``ShootCommand`` alongside a feedforward to spin the shooter flywheel to the specified velocity. Once the ``PIDController`` reaches the specified velocity, the ``ShootCommand`` runs the feeder.