Swerve Simulation#

The API supports a functionality focused simulation. This means that the simulation API assumes that the swerve drive is perfect (no scrub and no wheel slip). Additionally, it assumes the inertia of the steer module and the drive modules. Robot-wide, rotational and translational inertia is not accounted for.

To update the simulated swerve robot state, ensure m_drivetrain.updateSimState(0.02, 12) (m_drivetrain is a SwerveDrivetrain, 0.02 is the loop update rate, and 12 is the battery voltage) is called in simulationPeriodic().

Java

@Override
public void simulationPeriodic() {
   /* Assume 20ms update rate, 12v battery voltage */
   updateSimState(0.02, 12);
}

Note

When utilizing CommandSwerveDrivetrain (via example, or Tuner X), this is handled in the subsystem simulationPeriodic instead.

Simulation FAQ#

Q: My robot does not move in simulation#

A: Verify that all gains are non-zero and that the steer/drive inertia is non-zero.

Q: My robot stutters when driving#

A: Simulation uses predetermined constants that represent the drivetrain, as such, gains may be inaccurate compared to the real robot.