text: #pragma once
  
  #include "estimation/filter.hh"
  #include "estimation/jet/jet_rk4.hh"
  #include "estimation/observation_model.hh"
  
  namespace estimation {
  namespace jet_filter {
  
  using JetEkf = Ekf<State>;
  using ImuModel = ObservationModel<State, AccelMeasurement>;
  
  struct FiducialMeasurement {
    int fiducial_id = -1;
    SE3 T_fiducial_from_camera;
    static constexpr int DIM = 6;
  };
  
  }  // namespace jet_filter
  }  // namespace estimation