y2022/localizer/localizer_status.fbs

include "frc971/control_loops/drivetrain/drivetrain_status.fbs";

namespace frc971.controls;

// Stores the state associated with the acceleration-based modelling.
table AccelBasedState {
  // x/y position, in meters.
  x:double (id: 0);
  y:double (id: 1);
  // heading, in radians.
  theta:double (id: 2);
  // Velocity in X/Y directions, in m/s.
  velocity_x:double (id: 3);
  velocity_y:double (id: 4);
}

// Stores the state associated with the drivetrain model-based state.
// This model assumes zero lateral motion of the drivetrain.
table ModelBasedState {
  // x/y position, in meters.
  x:double (id: 0);
  y:double (id: 1);
  // heading, in radians.
  theta:double (id: 2);
  // Expected encoder reading for the left side of the drivetrain, in meters.
  left_encoder:double (id: 3);
  // Modelled velocity of the left side of the drivetrain, in meters / second.
  left_velocity:double (id: 4);
  // Estimated voltage error, in volts.
  left_voltage_error:double (id: 5);
  // Same as the left_* fields, but for the right side of the drivetrain.
  right_encoder:double (id: 6);
  right_velocity:double (id: 7);
  right_voltage_error:double (id: 8);
}

table ModelBasedStatus {
  // Current acceleration and model-based states. Depending on using_model,
  // one of these will be the ground-truth and the other will be calculated
  // based on it. E.g. if using_model is true, then model_state will be
  // populated as you'd expect, while accel_state will be populated to be
  // consistent with model_state (e.g., no lateral motion).
  accel_state:AccelBasedState (id: 0);
  model_state:ModelBasedState (id: 1);
  // using_model indicates whether we are currently in in model-based or
  // accelerometer-based estimation.
  using_model:bool (id: 2);
  // Current residual associated with the amount of inconsistency between
  // the two models. Will be zero if the drivetrain model is perfectly
  // consistent with the IMU readings.
  residual:double (id: 3);
  // Status from the down estimator.
  down_estimator:frc971.control_loops.drivetrain.DownEstimatorState (id: 4);
  // Current ground-truth for x/y/theta. Should match those present in *_state.
  x:double (id: 5);
  y:double (id: 6);
  theta:double (id: 7);
  // Current accelerations implied by the current accelerometer + down estimator
  // + yaw readings.
  implied_accel_x:double (id: 8);
  implied_accel_y:double (id: 9);
  implied_accel_z:double (id: 10);
  // oldest_* are the oldest surviving branches of the model that have just been
  // running purely on one model.
  oldest_accel_state:AccelBasedState (id: 11);
  oldest_model_state:ModelBasedState (id: 12);
  // Filtered version of the residual field--this is what is actually used by
  // the code for determining when to swap between modes.
  filtered_residual:double (id: 13);
  // Components of the residual. Useful for debugging.
  velocity_residual:double (id: 14);
  accel_residual:double (id: 15);
  theta_rate_residual:double (id: 16);
  // Number of times we have missed an IMU reading. Should never increase except
  // *maybe* during startup.
  clock_resets:int (id: 17);
}

table LocalizerStatus {
  model_based:ModelBasedStatus (id: 0);
  // Whether the IMU is zeroed or not.
  zeroed:bool (id: 1);
  // Whether the IMU zeroing is faulted or not.
  faulted_zero:bool (id: 2);
  zeroing:control_loops.drivetrain.ImuZeroerState (id: 3);
  // Offset between the pico clock and the pi clock, such that
  // pico_timestamp + pico_offset_ns = pi_timestamp
  pico_offset_ns:int64 (id: 4);
  // Error in the offset, if we assume that the pi/pico clocks are identical and
  // that there is a perfectly consistent latency between the two. Will be zero
  // for the very first cycle, and then referenced off of the initial offset
  // thereafter. If greater than zero, implies that the pico is "behind",
  // whether due to unusually large latency or due to clock drift.
  pico_offset_error_ns:int64 (id: 5);
  left_encoder:double (id: 6);
  right_encoder:double (id: 7);
}

root_type LocalizerStatus;