Ejemplo n.º 1
0
    def __init__(self):
        self.dim_state = self.x_initial.shape[0]

        # init filter
        self.filter = EKF_sym(self.name,
                              self.Q,
                              self.x_initial,
                              self.P_initial,
                              self.dim_state,
                              self.dim_state,
                              maha_test_kinds=self.maha_test_kinds)
Ejemplo n.º 2
0
  def __init__(self):
    self.dim_state = self.initial_x.shape[0]
    self.dim_state_err = self.initial_P_diag.shape[0]

    self.obs_noise = {ObservationKind.ODOMETRIC_SPEED: np.atleast_2d(0.2**2),
                      ObservationKind.PHONE_GYRO: np.diag([0.025**2, 0.025**2, 0.025**2]),
                      ObservationKind.PHONE_ACCEL: np.diag([.5**2, .5**2, .5**2]),
                      ObservationKind.CAMERA_ODO_ROTATION: np.diag([0.05**2, 0.05**2, 0.05**2]),
                      ObservationKind.IMU_FRAME: np.diag([0.05**2, 0.05**2, 0.05**2]),
                      ObservationKind.NO_ROT: np.diag([0.00025**2, 0.00025**2, 0.00025**2]),
                      ObservationKind.ECEF_POS: np.diag([5**2, 5**2, 5**2])}

    # init filter
    self.filter = EKF_sym(self.name, self.Q, self.initial_x, np.diag(self.initial_P_diag), self.dim_state, self.dim_state_err)
Ejemplo n.º 3
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    def __init__(self, steer_ratio=15, stiffness_factor=1, angle_offset=0):
        self.dim_state = self.x_initial.shape[0]
        x_init = self.x_initial
        x_init[States.STEER_RATIO] = steer_ratio
        x_init[States.STIFFNESS] = stiffness_factor
        x_init[States.ANGLE_OFFSET] = angle_offset

        # init filter
        self.filter = EKF_sym(self.name,
                              self.Q,
                              self.x_initial,
                              self.P_initial,
                              self.dim_state,
                              self.dim_state,
                              maha_test_kinds=self.maha_test_kinds,
                              global_vars=self.global_vars)
Ejemplo n.º 4
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    def __init__(self, N=4, max_tracks=3000):
        name = f"{self.name}_{N}"

        self.obs_noise = {
            ObservationKind.ODOMETRIC_SPEED:
            np.atleast_2d(0.2**2),
            ObservationKind.PHONE_GYRO:
            np.diag([0.025**2, 0.025**2, 0.025**2]),
            ObservationKind.PHONE_ACCEL:
            np.diag([.5**2, .5**2, .5**2]),
            ObservationKind.CAMERA_ODO_ROTATION:
            np.diag([0.05**2, 0.05**2, 0.05**2]),
            ObservationKind.IMU_FRAME:
            np.diag([0.05**2, 0.05**2, 0.05**2]),
            ObservationKind.NO_ROT:
            np.diag([0.00025**2, 0.00025**2, 0.00025**2]),
            ObservationKind.ECEF_POS:
            np.diag([5**2, 5**2, 5**2])
        }

        # MSCKF stuff
        self.N = N
        self.dim_main = LocKalman.x_initial.shape[0]
        self.dim_main_err = LocKalman.P_initial.shape[0]
        self.dim_state = self.dim_main + self.dim_augment * self.N
        self.dim_state_err = self.dim_main_err + self.dim_augment_err * self.N

        if self.N > 0:
            x_initial, P_initial, Q = self.pad_augmented(
                self.x_initial, self.P_initial, self.Q)
            self.computer = LstSqComputer(N)
            self.max_tracks = max_tracks

        # init filter
        self.filter = EKF_sym(name, Q, x_initial, P_initial, self.dim_main,
                              self.dim_main_err, N, self.dim_augment,
                              self.dim_augment_err, self.maha_test_kinds)
Ejemplo n.º 5
0
class GNSSKalman():
  name = 'gnss'

  x_initial = np.array([-2712700.6008, -4281600.6679, 3859300.1830,
                        0, 0, 0,
                        0, 0, 0,
                        0, 0])

  # state covariance
  P_initial = np.diag([10000**2, 10000**2, 10000**2,
                       10**2, 10**2, 10**2,
                       (2000000)**2, (100)**2, (0.5)**2,
                       (10)**2, (1)**2])

  # process noise
  Q = np.diag([0.3**2, 0.3**2, 0.3**2,
               3**2, 3**2, 3**2,
               (.1)**2, (0)**2, (0.01)**2,
               .1**2, (.01)**2])

  maha_test_kinds: List[int] = []  # ObservationKind.PSEUDORANGE_RATE, ObservationKind.PSEUDORANGE, ObservationKind.PSEUDORANGE_GLONASS]

  @staticmethod
  def generate_code():
    dim_state = GNSSKalman.x_initial.shape[0]
    name = GNSSKalman.name
    maha_test_kinds = GNSSKalman.maha_test_kinds

    # make functions and jacobians with sympy
    # state variables
    state_sym = sp.MatrixSymbol('state', dim_state, 1)
    state = sp.Matrix(state_sym)
    x, y, z = state[0:3, :]
    v = state[3:6, :]
    vx, vy, vz = v
    cb, cd, ca = state[6:9, :]
    glonass_bias, glonass_freq_slope = state[9:11, :]

    dt = sp.Symbol('dt')

    state_dot = sp.Matrix(np.zeros((dim_state, 1)))
    state_dot[:3, :] = v
    state_dot[6, 0] = cd
    state_dot[7, 0] = ca

    # Basic descretization, 1st order integrator
    # Can be pretty bad if dt is big
    f_sym = state + dt * state_dot

    #
    # Observation functions
    #

    # extra args
    sat_pos_freq_sym = sp.MatrixSymbol('sat_pos', 4, 1)
    sat_pos_vel_sym = sp.MatrixSymbol('sat_pos_vel', 6, 1)
    sat_los_sym = sp.MatrixSymbol('sat_los', 3, 1)
    orb_epos_sym = sp.MatrixSymbol('orb_epos_sym', 3, 1)

    # expand extra args
    sat_x, sat_y, sat_z, glonass_freq = sat_pos_freq_sym
    sat_vx, sat_vy, sat_vz = sat_pos_vel_sym[3:]
    los_x, los_y, los_z = sat_los_sym
    orb_x, orb_y, orb_z = orb_epos_sym

    h_pseudorange_sym = sp.Matrix([
      sp.sqrt(
        (x - sat_x)**2 +
        (y - sat_y)**2 +
        (z - sat_z)**2
      ) + cb
    ])

    h_pseudorange_glonass_sym = sp.Matrix([
      sp.sqrt(
        (x - sat_x)**2 +
        (y - sat_y)**2 +
        (z - sat_z)**2
      ) + cb + glonass_bias + glonass_freq_slope * glonass_freq
    ])

    los_vector = (sp.Matrix(sat_pos_vel_sym[0:3]) - sp.Matrix([x, y, z]))
    los_vector = los_vector / sp.sqrt(los_vector[0]**2 + los_vector[1]**2 + los_vector[2]**2)
    h_pseudorange_rate_sym = sp.Matrix([los_vector[0] * (sat_vx - vx) +
                                        los_vector[1] * (sat_vy - vy) +
                                        los_vector[2] * (sat_vz - vz) +
                                        cd])

    obs_eqs = [[h_pseudorange_sym, ObservationKind.PSEUDORANGE_GPS, sat_pos_freq_sym],
               [h_pseudorange_glonass_sym, ObservationKind.PSEUDORANGE_GLONASS, sat_pos_freq_sym],
               [h_pseudorange_rate_sym, ObservationKind.PSEUDORANGE_RATE_GPS, sat_pos_vel_sym],
               [h_pseudorange_rate_sym, ObservationKind.PSEUDORANGE_RATE_GLONASS, sat_pos_vel_sym]]

    gen_code(name, f_sym, dt, state_sym, obs_eqs, dim_state, dim_state, maha_test_kinds=maha_test_kinds)

  def __init__(self):
    self.dim_state = self.x_initial.shape[0]

    # init filter
    self.filter = EKF_sym(self.name, self.Q, self.x_initial, self.P_initial, self.dim_state, self.dim_state, maha_test_kinds=self.maha_test_kinds)

  @property
  def x(self):
    return self.filter.state()

  @property
  def P(self):
    return self.filter.covs()

  def predict(self, t):
    return self.filter.predict(t)

  def rts_smooth(self, estimates):
    return self.filter.rts_smooth(estimates, norm_quats=False)

  def init_state(self, state, covs_diag=None, covs=None, filter_time=None):
    if covs_diag is not None:
      P = np.diag(covs_diag)
    elif covs is not None:
      P = covs
    else:
      P = self.filter.covs()
    self.filter.init_state(state, P, filter_time)

  def predict_and_observe(self, t, kind, data):
    if len(data) > 0:
      data = np.atleast_2d(data)
    if kind == ObservationKind.PSEUDORANGE_GPS or kind == ObservationKind.PSEUDORANGE_GLONASS:
      r = self.predict_and_update_pseudorange(data, t, kind)
    elif kind == ObservationKind.PSEUDORANGE_RATE_GPS or kind == ObservationKind.PSEUDORANGE_RATE_GLONASS:
      r = self.predict_and_update_pseudorange_rate(data, t, kind)
    return r

  def predict_and_update_pseudorange(self, meas, t, kind):
    R = np.zeros((len(meas), 1, 1))
    sat_pos_freq = np.zeros((len(meas), 4))
    z = np.zeros((len(meas), 1))
    for i, m in enumerate(meas):
      z_i, R_i, sat_pos_freq_i = parse_pr(m)
      sat_pos_freq[i, :] = sat_pos_freq_i
      z[i, :] = z_i
      R[i, :, :] = R_i
    return self.filter.predict_and_update_batch(t, kind, z, R, sat_pos_freq)

  def predict_and_update_pseudorange_rate(self, meas, t, kind):
    R = np.zeros((len(meas), 1, 1))
    z = np.zeros((len(meas), 1))
    sat_pos_vel = np.zeros((len(meas), 6))
    for i, m in enumerate(meas):
      z_i, R_i, sat_pos_vel_i = parse_prr(m)
      sat_pos_vel[i] = sat_pos_vel_i
      R[i, :, :] = R_i
      z[i, :] = z_i
    return self.filter.predict_and_update_batch(t, kind, z, R, sat_pos_vel)
Ejemplo n.º 6
0
class LocKalman():
    name = "loc"
    x_initial = np.array([
        -2.7e6, 4.2e6, 3.8e6, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1,
        0, 0, 0, 1, 0, 0, 0, 0, 0, 0
    ])

    # state covariance
    P_initial = np.diag([
        10000**2, 10000**2,
        10000**2, 10**2, 10**2, 10**2, 10**2, 10**2, 10**2, 1**2, 1**2, 1**2,
        (200000)**2, (100)**2, 0.05**2, 0.05**2, 0.05**2, 0.02**2, 1**2, 1**2,
        1**2, 0.01**2, (0.01)**2, (0.01)**2, (0.01)**2, 10**2, 1**2, 0.05**2
    ])

    # process noise
    Q = np.diag([
        0.03**2, 0.03**2, 0.03**2, 0.0**2, 0.0**2, 0.0**2, 0.0**2, 0.0**2,
        0.0**2, 0.1**2, 0.1**2, 0.1**2, (.1)**2, (0.0)**2, (0.005 / 100)**2,
        (0.005 / 100)**2, (0.005 / 100)**2, (0.02 / 100)**2, 3**2,
        3**2, 3**2, 0.001**2, (0.05 / 60)**2, (0.05 / 60)**2, (0.05 / 60)**2,
        (.1)**2, (.01)**2, 0.005**2
    ])

    # measurements that need to pass mahalanobis distance outlier rejector
    maha_test_kinds = [
        ObservationKind.ORB_FEATURES
    ]  # , ObservationKind.PSEUDORANGE, ObservationKind.PSEUDORANGE_RATE]
    dim_augment = 7
    dim_augment_err = 6

    @staticmethod
    def generate_code(N=4):
        dim_augment = LocKalman.dim_augment
        dim_augment_err = LocKalman.dim_augment_err

        dim_main = LocKalman.x_initial.shape[0]
        dim_main_err = LocKalman.P_initial.shape[0]
        dim_state = dim_main + dim_augment * N
        dim_state_err = dim_main_err + dim_augment_err * N
        maha_test_kinds = LocKalman.maha_test_kinds

        name = f"{LocKalman.name}_{N}"

        # make functions and jacobians with sympy
        # state variables
        state_sym = sp.MatrixSymbol('state', dim_state, 1)
        state = sp.Matrix(state_sym)
        x, y, z = state[States.ECEF_POS, :]
        q = state[States.ECEF_ORIENTATION, :]
        v = state[States.ECEF_VELOCITY, :]
        vx, vy, vz = v
        omega = state[States.ANGULAR_VELOCITY, :]
        vroll, vpitch, vyaw = omega
        #cb = state[States.CLOCK_BIAS, :][0, 0]
        #cd = state[States.CLOCK_DRIFT, :][0, 0]
        cb, cd = state[13:15, :]
        roll_bias, pitch_bias, yaw_bias = state[States.GYRO_BIAS, :]
        #odo_scale = state[States.ODO_SCALE, :][0,0]
        odo_scale = state[18, :]
        acceleration = state[States.ACCELERATION, :]
        #focal_scale = state[States.FOCAL_SCALE, :][0,0]
        focal_scale = state[22, :]
        imu_angles = state[States.IMU_OFFSET, :]
        glonass_bias, glonass_freq_slope = state[26:28, :]
        ca = state[28, 0]
        #glonass_bias = state[States.GLONASS_BIAS, :][0,0]
        #glonass_freq_slope = state[States.GLONASS_FREQ_SLOPE, :][0,0]
        #ca = state[States.CLOCK_ACCELERATION, :][0,0]

        dt = sp.Symbol('dt')

        # calibration and attitude rotation matrices
        quat_rot = quat_rotate(*q)

        # Got the quat predict equations from here
        # A New Quaternion-Based Kalman Filter for
        # Real-Time Attitude Estimation Using the Two-Step
        # Geometrically-Intuitive Correction Algorithm
        A = 0.5 * sp.Matrix(
            [[0, -vroll, -vpitch, -vyaw], [vroll, 0, vyaw, -vpitch],
             [vpitch, -vyaw, 0, vroll], [vyaw, vpitch, -vroll, 0]])
        q_dot = A * q

        # Time derivative of the state as a function of state
        state_dot = sp.Matrix(np.zeros((dim_state, 1)))
        state_dot[States.ECEF_POS, :] = v
        state_dot[States.ECEF_ORIENTATION, :] = q_dot
        state_dot[States.ECEF_VELOCITY, 0] = quat_rot * acceleration
        state_dot[13, 0] = cd
        state_dot[14, 0] = ca
        #state_dot[States.CLOCK_BIAS, 0][0,0] = cd
        state_dot[States.CLOCK_DRIFT, 0][0, 0] = ca

        # Basic descretization, 1st order intergrator
        # Can be pretty bad if dt is big
        f_sym = state + dt * state_dot

        state_err_sym = sp.MatrixSymbol('state_err', dim_state_err, 1)
        state_err = sp.Matrix(state_err_sym)
        quat_err = state_err[States.ECEF_ORIENTATION_ERR, :]
        v_err = state_err[States.ECEF_VELOCITY_ERR, :]
        omega_err = state_err[States.ANGULAR_VELOCITY_ERR, :]
        #cd_err = state_err[States.CLOCK_DRIFT_ERR, :][0,:]
        cd_err = state_err[13, :]
        acceleration_err = state_err[States.ACCELERATION_ERR, :]
        ca_err = state_err[27, :]

        # Time derivative of the state error as a function of state error and state
        quat_err_matrix = euler_rotate(quat_err[0], quat_err[1], quat_err[2])
        q_err_dot = quat_err_matrix * quat_rot * (omega + omega_err)
        state_err_dot = sp.Matrix(np.zeros((dim_state_err, 1)))
        state_err_dot[States.ECEF_POS_ERR, :] = v_err
        state_err_dot[States.ECEF_ORIENTATION_ERR, :] = q_err_dot
        state_err_dot[
            States.ECEF_VELOCITY_ERR, :] = quat_err_matrix * quat_rot * (
                acceleration + acceleration_err)
        #state_err_dot[States.CLOCK_BIAS_ERR, :][0,:] = cd_err
        #state_err_dot[States.CLOCK_DRIFT_ERR, :][0,:] = ca_err
        state_err_dot[12, :][0, :] = cd_err
        state_err_dot[13, :][0, :] = ca_err
        f_err_sym = state_err + dt * state_err_dot

        # convenient indexing
        # q idxs are for quats and p idxs are for other
        q_idxs = [[3, dim_augment]] + [[
            dim_main + n * dim_augment + 3, dim_main + (n + 1) * dim_augment
        ] for n in range(N)]
        q_err_idxs = [[3, dim_augment_err]] + [[
            dim_main_err + n * dim_augment_err + 3, dim_main_err +
            (n + 1) * dim_augment_err
        ] for n in range(N)]
        p_idxs = [[0, 3]] + [[dim_augment, dim_main]] + [[
            dim_main + n * dim_augment, dim_main + n * dim_augment + 3
        ] for n in range(N)]
        p_err_idxs = [[0, 3]] + [[dim_augment_err, dim_main_err]] + [[
            dim_main_err + n * dim_augment_err,
            dim_main_err + n * dim_augment_err + 3
        ] for n in range(N)]

        # Observation matrix modifier
        H_mod_sym = sp.Matrix(np.zeros((dim_state, dim_state_err)))
        for p_idx, p_err_idx in zip(p_idxs, p_err_idxs):
            H_mod_sym[p_idx[0]:p_idx[1],
                      p_err_idx[0]:p_err_idx[1]] = np.eye(p_idx[1] - p_idx[0])
        for q_idx, q_err_idx in zip(q_idxs, q_err_idxs):
            H_mod_sym[q_idx[0]:q_idx[1],
                      q_err_idx[0]:q_err_idx[1]] = 0.5 * quat_matrix_r(
                          state[q_idx[0]:q_idx[1]])[:, 1:]

        # these error functions are defined so that say there
        # is a nominal x and true x:
        # true x = err_function(nominal x, delta x)
        # delta x = inv_err_function(nominal x, true x)
        nom_x = sp.MatrixSymbol('nom_x', dim_state, 1)
        true_x = sp.MatrixSymbol('true_x', dim_state, 1)
        delta_x = sp.MatrixSymbol('delta_x', dim_state_err, 1)

        err_function_sym = sp.Matrix(np.zeros((dim_state, 1)))
        for q_idx, q_err_idx in zip(q_idxs, q_err_idxs):
            delta_quat = sp.Matrix(np.ones(4))
            delta_quat[1:, :] = sp.Matrix(
                0.5 * delta_x[q_err_idx[0]:q_err_idx[1], :])
            err_function_sym[q_idx[0]:q_idx[1], 0] = quat_matrix_r(
                nom_x[q_idx[0]:q_idx[1], 0]) * delta_quat
        for p_idx, p_err_idx in zip(p_idxs, p_err_idxs):
            err_function_sym[p_idx[0]:p_idx[1], :] = sp.Matrix(
                nom_x[p_idx[0]:p_idx[1], :] +
                delta_x[p_err_idx[0]:p_err_idx[1], :])

        inv_err_function_sym = sp.Matrix(np.zeros((dim_state_err, 1)))
        for p_idx, p_err_idx in zip(p_idxs, p_err_idxs):
            inv_err_function_sym[p_err_idx[0]:p_err_idx[1],
                                 0] = sp.Matrix(-nom_x[p_idx[0]:p_idx[1], 0] +
                                                true_x[p_idx[0]:p_idx[1], 0])
        for q_idx, q_err_idx in zip(q_idxs, q_err_idxs):
            delta_quat = quat_matrix_r(
                nom_x[q_idx[0]:q_idx[1], 0]).T * true_x[q_idx[0]:q_idx[1], 0]
            inv_err_function_sym[q_err_idx[0]:q_err_idx[1],
                                 0] = sp.Matrix(2 * delta_quat[1:])

        eskf_params = [[err_function_sym, nom_x, delta_x],
                       [inv_err_function_sym, nom_x, true_x], H_mod_sym,
                       f_err_sym, state_err_sym]
        #
        # Observation functions
        #

        # extra args
        sat_pos_freq_sym = sp.MatrixSymbol('sat_pos', 4, 1)
        sat_pos_vel_sym = sp.MatrixSymbol('sat_pos_vel', 6, 1)
        sat_los_sym = sp.MatrixSymbol('sat_los', 3, 1)
        orb_epos_sym = sp.MatrixSymbol('orb_epos_sym', 3, 1)

        # expand extra args
        sat_x, sat_y, sat_z, glonass_freq = sat_pos_freq_sym
        sat_vx, sat_vy, sat_vz = sat_pos_vel_sym[3:]
        los_x, los_y, los_z = sat_los_sym
        orb_x, orb_y, orb_z = orb_epos_sym

        h_pseudorange_sym = sp.Matrix(
            [sp.sqrt((x - sat_x)**2 + (y - sat_y)**2 + (z - sat_z)**2) + cb])

        h_pseudorange_glonass_sym = sp.Matrix([
            sp.sqrt((x - sat_x)**2 + (y - sat_y)**2 + (z - sat_z)**2) + cb +
            glonass_bias + glonass_freq_slope * glonass_freq
        ])

        los_vector = (sp.Matrix(sat_pos_vel_sym[0:3]) - sp.Matrix([x, y, z]))
        los_vector = los_vector / sp.sqrt(los_vector[0]**2 + los_vector[1]**2 +
                                          los_vector[2]**2)
        h_pseudorange_rate_sym = sp.Matrix([
            los_vector[0] * (sat_vx - vx) + los_vector[1] * (sat_vy - vy) +
            los_vector[2] * (sat_vz - vz) + cd
        ])

        imu_rot = euler_rotate(*imu_angles)
        h_gyro_sym = imu_rot * sp.Matrix(
            [vroll + roll_bias, vpitch + pitch_bias, vyaw + yaw_bias])

        pos = sp.Matrix([x, y, z])
        gravity = quat_rot.T * ((EARTH_GM /
                                 ((x**2 + y**2 + z**2)**(3.0 / 2.0))) * pos)
        h_acc_sym = imu_rot * (gravity + acceleration)
        h_phone_rot_sym = sp.Matrix([vroll, vpitch, vyaw])

        speed = sp.sqrt(vx**2 + vy**2 + vz**2)
        h_speed_sym = sp.Matrix([speed * odo_scale])

        # orb stuff
        orb_pos_sym = sp.Matrix([orb_x - x, orb_y - y, orb_z - z])
        orb_pos_rot_sym = quat_rot.T * orb_pos_sym
        s = orb_pos_rot_sym[0]
        h_orb_point_sym = sp.Matrix([(1 / s) * (orb_pos_rot_sym[1]),
                                     (1 / s) * (orb_pos_rot_sym[2])])

        h_pos_sym = sp.Matrix([x, y, z])
        h_imu_frame_sym = sp.Matrix(imu_angles)

        h_relative_motion = sp.Matrix(quat_rot.T * v)

        obs_eqs = [
            [h_speed_sym, ObservationKind.ODOMETRIC_SPEED, None],
            [h_gyro_sym, ObservationKind.PHONE_GYRO, None],
            [h_phone_rot_sym, ObservationKind.NO_ROT, None],
            [h_acc_sym, ObservationKind.PHONE_ACCEL, None],
            [
                h_pseudorange_sym, ObservationKind.PSEUDORANGE_GPS,
                sat_pos_freq_sym
            ],
            [
                h_pseudorange_glonass_sym, ObservationKind.PSEUDORANGE_GLONASS,
                sat_pos_freq_sym
            ],
            [
                h_pseudorange_rate_sym, ObservationKind.PSEUDORANGE_RATE_GPS,
                sat_pos_vel_sym
            ],
            [
                h_pseudorange_rate_sym,
                ObservationKind.PSEUDORANGE_RATE_GLONASS, sat_pos_vel_sym
            ], [h_pos_sym, ObservationKind.ECEF_POS, None],
            [h_relative_motion, ObservationKind.CAMERA_ODO_TRANSLATION, None],
            [h_phone_rot_sym, ObservationKind.CAMERA_ODO_ROTATION, None],
            [h_imu_frame_sym, ObservationKind.IMU_FRAME, None],
            [h_orb_point_sym, ObservationKind.ORB_POINT, orb_epos_sym]
        ]

        # MSCKF configuration
        if N > 0:
            focal_scale = 1
            # Add observation functions for orb feature tracks
            track_epos_sym = sp.MatrixSymbol('track_epos_sym', 3, 1)
            track_x, track_y, track_z = track_epos_sym
            h_track_sym = sp.Matrix(np.zeros(((1 + N) * 2, 1)))
            track_pos_sym = sp.Matrix([track_x - x, track_y - y, track_z - z])
            track_pos_rot_sym = quat_rot.T * track_pos_sym
            h_track_sym[-2:, :] = sp.Matrix([
                focal_scale * (track_pos_rot_sym[1] / track_pos_rot_sym[0]),
                focal_scale * (track_pos_rot_sym[2] / track_pos_rot_sym[0])
            ])

            h_msckf_test_sym = sp.Matrix(np.zeros(((1 + N) * 3, 1)))
            h_msckf_test_sym[-3:, :] = sp.Matrix(
                [track_x - x, track_y - y, track_z - z])

            for n in range(N):
                idx = dim_main + n * dim_augment
                # err_idx = dim_main_err + n * dim_augment_err  # FIXME: Why is this not used?
                x, y, z = state[idx:idx + 3]
                q = state[idx + 3:idx + 7]
                quat_rot = quat_rotate(*q)
                track_pos_sym = sp.Matrix(
                    [track_x - x, track_y - y, track_z - z])
                track_pos_rot_sym = quat_rot.T * track_pos_sym
                h_track_sym[n * 2:n * 2 + 2, :] = sp.Matrix([
                    focal_scale *
                    (track_pos_rot_sym[1] / track_pos_rot_sym[0]),
                    focal_scale * (track_pos_rot_sym[2] / track_pos_rot_sym[0])
                ])
                h_msckf_test_sym[n * 3:n * 3 + 3, :] = sp.Matrix(
                    [track_x - x, track_y - y, track_z - z])

            obs_eqs.append(
                [h_msckf_test_sym, ObservationKind.MSCKF_TEST, track_epos_sym])
            obs_eqs.append(
                [h_track_sym, ObservationKind.ORB_FEATURES, track_epos_sym])
            obs_eqs.append([
                h_track_sym, ObservationKind.FEATURE_TRACK_TEST, track_epos_sym
            ])
            msckf_params = [
                dim_main, dim_augment, dim_main_err, dim_augment_err, N,
                [ObservationKind.MSCKF_TEST, ObservationKind.ORB_FEATURES]
            ]
        else:
            msckf_params = None
        gen_code(name, f_sym, dt, state_sym, obs_eqs, dim_state, dim_state_err,
                 eskf_params, msckf_params, maha_test_kinds)

    def __init__(self, N=4, max_tracks=3000):
        name = f"{self.name}_{N}"

        self.obs_noise = {
            ObservationKind.ODOMETRIC_SPEED:
            np.atleast_2d(0.2**2),
            ObservationKind.PHONE_GYRO:
            np.diag([0.025**2, 0.025**2, 0.025**2]),
            ObservationKind.PHONE_ACCEL:
            np.diag([.5**2, .5**2, .5**2]),
            ObservationKind.CAMERA_ODO_ROTATION:
            np.diag([0.05**2, 0.05**2, 0.05**2]),
            ObservationKind.IMU_FRAME:
            np.diag([0.05**2, 0.05**2, 0.05**2]),
            ObservationKind.NO_ROT:
            np.diag([0.00025**2, 0.00025**2, 0.00025**2]),
            ObservationKind.ECEF_POS:
            np.diag([5**2, 5**2, 5**2])
        }

        # MSCKF stuff
        self.N = N
        self.dim_main = LocKalman.x_initial.shape[0]
        self.dim_main_err = LocKalman.P_initial.shape[0]
        self.dim_state = self.dim_main + self.dim_augment * self.N
        self.dim_state_err = self.dim_main_err + self.dim_augment_err * self.N

        if self.N > 0:
            x_initial, P_initial, Q = self.pad_augmented(
                self.x_initial, self.P_initial, self.Q)
            self.computer = LstSqComputer(N)
            self.max_tracks = max_tracks

        # init filter
        self.filter = EKF_sym(name, Q, x_initial, P_initial, self.dim_main,
                              self.dim_main_err, N, self.dim_augment,
                              self.dim_augment_err, self.maha_test_kinds)

    @property
    def x(self):
        return self.filter.state()

    @property
    def t(self):
        return self.filter.filter_time

    @property
    def P(self):
        return self.filter.covs()

    def predict(self, t):
        return self.filter.predict(t)

    def rts_smooth(self, estimates):
        return self.filter.rts_smooth(estimates, norm_quats=True)

    def pad_augmented(self, x, P, Q=None):
        if x.shape[0] == self.dim_main and self.N > 0:
            x = np.pad(x, (0, self.N * self.dim_augment), mode='constant')
            x[self.dim_main + 3::7] = 1
        if P.shape[0] == self.dim_main_err and self.N > 0:
            P = np.pad(P, [(0, self.N * self.dim_augment_err),
                           (0, self.N * self.dim_augment_err)],
                       mode='constant')
            P[self.dim_main_err:, self.dim_main_err:] = 10e20 * np.eye(
                self.dim_augment_err * self.N)
        if Q is None:
            return x, P
        else:
            Q = np.pad(Q, [(0, self.N * self.dim_augment_err),
                           (0, self.N * self.dim_augment_err)],
                       mode='constant')
            return x, P, Q

    def init_state(self, state, covs_diag=None, covs=None, filter_time=None):
        if covs_diag is not None:
            P = np.diag(covs_diag)
        elif covs is not None:
            P = covs
        else:
            P = self.filter.covs()
        state, P = self.pad_augmented(state, P)
        self.filter.init_state(state, P, filter_time)

    def predict_and_observe(self, t, kind, data):
        if len(data) > 0:
            data = np.atleast_2d(data)
        if kind == ObservationKind.CAMERA_ODO_TRANSLATION:
            r = self.predict_and_update_odo_trans(data, t, kind)
        elif kind == ObservationKind.CAMERA_ODO_ROTATION:
            r = self.predict_and_update_odo_rot(data, t, kind)
        elif kind == ObservationKind.PSEUDORANGE_GPS or kind == ObservationKind.PSEUDORANGE_GLONASS:
            r = self.predict_and_update_pseudorange(data, t, kind)
        elif kind == ObservationKind.PSEUDORANGE_RATE_GPS or kind == ObservationKind.PSEUDORANGE_RATE_GLONASS:
            r = self.predict_and_update_pseudorange_rate(data, t, kind)
        elif kind == ObservationKind.ORB_POINT:
            r = self.predict_and_update_orb(data, t, kind)
        elif kind == ObservationKind.ORB_FEATURES:
            r = self.predict_and_update_orb_features(data, t, kind)
        elif kind == ObservationKind.MSCKF_TEST:
            r = self.predict_and_update_msckf_test(data, t, kind)
        elif kind == ObservationKind.FEATURE_TRACK_TEST:
            r = self.predict_and_update_feature_track_test(data, t, kind)
        elif kind == ObservationKind.ODOMETRIC_SPEED:
            r = self.predict_and_update_odo_speed(data, t, kind)
        else:
            r = self.filter.predict_and_update_batch(
                t, kind, data, self.get_R(kind, len(data)))
        # Normalize quats
        quat_norm = np.linalg.norm(self.filter.x[3:7, 0])
        # Should not continue if the quats behave this weirdly
        if not 0.1 < quat_norm < 10:
            raise RuntimeError("Sir! The filter's gone all wobbly!")
        self.filter.x[3:7, 0] = self.filter.x[3:7, 0] / quat_norm
        for i in range(self.N):
            d1 = self.dim_main
            d3 = self.dim_augment
            self.filter.x[d1 + d3 * i + 3:d1 + d3 * i + 7] /= np.linalg.norm(
                self.filter.x[d1 + i * d3 + 3:d1 + i * d3 + 7, 0])
        return r

    def get_R(self, kind, n):
        obs_noise = self.obs_noise[kind]
        dim = obs_noise.shape[0]
        R = np.zeros((n, dim, dim))
        for i in range(n):
            R[i, :, :] = obs_noise
        return R

    def predict_and_update_pseudorange(self, meas, t, kind):
        R = np.zeros((len(meas), 1, 1))
        sat_pos_freq = np.zeros((len(meas), 4))
        z = np.zeros((len(meas), 1))
        for i, m in enumerate(meas):
            z_i, R_i, sat_pos_freq_i = parse_pr(m)
            sat_pos_freq[i, :] = sat_pos_freq_i
            z[i, :] = z_i
            R[i, :, :] = R_i
        return self.filter.predict_and_update_batch(t, kind, z, R,
                                                    sat_pos_freq)

    def predict_and_update_pseudorange_rate(self, meas, t, kind):
        R = np.zeros((len(meas), 1, 1))
        z = np.zeros((len(meas), 1))
        sat_pos_vel = np.zeros((len(meas), 6))
        for i, m in enumerate(meas):
            z_i, R_i, sat_pos_vel_i = parse_prr(m)
            sat_pos_vel[i] = sat_pos_vel_i
            R[i, :, :] = R_i
            z[i, :] = z_i
        return self.filter.predict_and_update_batch(t, kind, z, R, sat_pos_vel)

    def predict_and_update_orb(self, orb, t, kind):
        true_pos = orb[:, 2:]
        z = orb[:, :2]
        R = np.zeros((len(orb), 2, 2))
        for i, _ in enumerate(z):
            R[i, :, :] = np.diag([10**2, 10**2])
        return self.filter.predict_and_update_batch(t, kind, z, R, true_pos)

    def predict_and_update_odo_speed(self, speed, t, kind):
        z = np.array(speed)
        R = np.zeros((len(speed), 1, 1))
        for i, _ in enumerate(z):
            R[i, :, :] = np.diag([0.2**2])
        return self.filter.predict_and_update_batch(t, kind, z, R)

    def predict_and_update_odo_trans(self, trans, t, kind):
        z = trans[:, :3]
        R = np.zeros((len(trans), 3, 3))
        for i, _ in enumerate(z):
            R[i, :, :] = np.diag(trans[i, 3:]**2)
        return self.filter.predict_and_update_batch(t, kind, z, R)

    def predict_and_update_odo_rot(self, rot, t, kind):
        z = rot[:, :3]
        R = np.zeros((len(rot), 3, 3))
        for i, _ in enumerate(z):
            R[i, :, :] = np.diag(rot[i, 3:]**2)
        return self.filter.predict_and_update_batch(t, kind, z, R)

    def predict_and_update_orb_features(self, tracks, t, kind):
        k = 2 * (self.N + 1)
        R = np.zeros((len(tracks), k, k))
        z = np.zeros((len(tracks), k))
        ecef_pos = np.zeros((len(tracks), 3))
        ecef_pos[:] = np.nan
        poses = self.x[self.dim_main:].reshape((-1, 7))
        times = tracks.reshape((len(tracks), self.N + 1, 4))[:, :, 0]
        good_counter = 0
        if times.any() and np.allclose(
                times[0, :-1], self.filter.augment_times, rtol=1e-6):
            for i, track in enumerate(tracks):
                img_positions = track.reshape((self.N + 1, 4))[:, 2:]

                # TODO not perfect as last pose not used
                # img_positions = unroll_shutter(img_positions, poses, self.filter.state()[7:10], self.filter.state()[10:13], ecef_pos[i])

                ecef_pos[i] = self.computer.compute_pos(
                    poses, img_positions[:-1])
                z[i] = img_positions.flatten()
                R[i, :, :] = np.diag([0.005**2] * (k))
                if np.isfinite(ecef_pos[i][0]):
                    good_counter += 1
                    if good_counter > self.max_tracks:
                        break
        good_idxs = np.all(np.isfinite(ecef_pos), axis=1)
        # have to do some weird stuff here to keep
        # to have the observations input from mesh3d
        # consistent with the outputs of the filter
        # Probably should be replaced, not sure how.
        ret = self.filter.predict_and_update_batch(t,
                                                   kind,
                                                   z[good_idxs],
                                                   R[good_idxs],
                                                   ecef_pos[good_idxs],
                                                   augment=True)
        if ret is None:
            return

        y_full = np.zeros((z.shape[0], z.shape[1] - 3))
        if sum(good_idxs) > 0:
            y_full[good_idxs] = np.array(ret[6])
        ret = ret[:6] + (y_full, z, ecef_pos)
        return ret

    def predict_and_update_msckf_test(self, test_data, t, kind):
        assert self.N > 0
        z = test_data
        R = np.zeros((len(test_data), len(z[0]), len(z[0])))
        ecef_pos = [self.x[:3]]
        for i, _ in enumerate(z):
            R[i, :, :] = np.diag([0.1**2] * len(z[0]))
        ret = self.filter.predict_and_update_batch(t, kind, z, R, ecef_pos)
        self.filter.augment()
        return ret

    def maha_test_pseudorange(self, x, P, meas, kind, maha_thresh=.3):
        bools = []
        for i, m in enumerate(meas):
            z, R, sat_pos_freq = parse_pr(m)
            bools.append(
                self.filter.maha_test(x,
                                      P,
                                      kind,
                                      z,
                                      R,
                                      extra_args=sat_pos_freq,
                                      maha_thresh=maha_thresh))
        return np.array(bools)

    def maha_test_pseudorange_rate(self, x, P, meas, kind, maha_thresh=.999):
        bools = []
        for i, m in enumerate(meas):
            z, R, sat_pos_vel = parse_prr(m)
            bools.append(
                self.filter.maha_test(x,
                                      P,
                                      kind,
                                      z,
                                      R,
                                      extra_args=sat_pos_vel,
                                      maha_thresh=maha_thresh))
        return np.array(bools)
Ejemplo n.º 7
0
class CarKalman():
    name = 'car'

    x_initial = np.array([
        1.0,
        15.0,
        0.0,
        0.0,
        10.0,
        0.0,
        0.0,
        0.0,
    ])

    # state covariance
    P_initial = np.diag([
        0.1**2,
        0.1**2,
        math.radians(0.1)**2,
        math.radians(0.1)**2,
        10**2,
        10**2,
        1.0**2,
        1.0**2,
    ])

    # process noise
    Q = np.diag([
        (.05 / 100)**2,
        .0001**2,
        math.radians(0.001)**2,
        math.radians(0.05)**2,
        .1**2,
        .1**2,
        math.radians(0.1)**2,
        math.radians(0.1)**2,
    ])

    obs_noise = {
        ObservationKind.STEER_ANGLE: np.atleast_2d(math.radians(0.1)**2),
        ObservationKind.ANGLE_OFFSET_FAST: np.atleast_2d(math.radians(5.0)**2),
        ObservationKind.STEER_RATIO: np.atleast_2d(50.0**2),
        ObservationKind.STIFFNESS: np.atleast_2d(50.0**2),
    }

    maha_test_kinds: List[int] = [
    ]  # [ObservationKind.ROAD_FRAME_YAW_RATE, ObservationKind.ROAD_FRAME_XY_SPEED]
    global_vars = [
        sp.Symbol('mass'),
        sp.Symbol('rotational_inertia'),
        sp.Symbol('center_to_front'),
        sp.Symbol('center_to_rear'),
        sp.Symbol('stiffness_front'),
        sp.Symbol('stiffness_rear'),
    ]

    @staticmethod
    def generate_code():
        dim_state = CarKalman.x_initial.shape[0]
        name = CarKalman.name
        maha_test_kinds = CarKalman.maha_test_kinds

        # globals
        m, j, aF, aR, cF_orig, cR_orig = CarKalman.global_vars

        # make functions and jacobians with sympy
        # state variables
        state_sym = sp.MatrixSymbol('state', dim_state, 1)
        state = sp.Matrix(state_sym)

        # Vehicle model constants
        x = state[States.STIFFNESS, :][0, 0]

        cF, cR = x * cF_orig, x * cR_orig
        angle_offset = state[States.ANGLE_OFFSET, :][0, 0]
        angle_offset_fast = state[States.ANGLE_OFFSET_FAST, :][0, 0]
        sa = state[States.STEER_ANGLE, :][0, 0]

        sR = state[States.STEER_RATIO, :][0, 0]
        u, v = state[States.VELOCITY, :]
        r = state[States.YAW_RATE, :][0, 0]

        A = sp.Matrix(np.zeros((2, 2)))
        A[0, 0] = -(cF + cR) / (m * u)
        A[0, 1] = -(cF * aF - cR * aR) / (m * u) - u
        A[1, 0] = -(cF * aF - cR * aR) / (j * u)
        A[1, 1] = -(cF * aF**2 + cR * aR**2) / (j * u)

        B = sp.Matrix(np.zeros((2, 1)))
        B[0, 0] = cF / m / sR
        B[1, 0] = (cF * aF) / j / sR

        x = sp.Matrix([v, r])  # lateral velocity, yaw rate
        x_dot = A * x + B * (sa - angle_offset - angle_offset_fast)

        dt = sp.Symbol('dt')
        state_dot = sp.Matrix(np.zeros((dim_state, 1)))
        state_dot[States.VELOCITY.start + 1, 0] = x_dot[0]
        state_dot[States.YAW_RATE.start, 0] = x_dot[1]

        # Basic descretization, 1st order integrator
        # Can be pretty bad if dt is big
        f_sym = state + dt * state_dot

        #
        # Observation functions
        #
        obs_eqs = [
            [sp.Matrix([r]), ObservationKind.ROAD_FRAME_YAW_RATE, None],
            [sp.Matrix([u, v]), ObservationKind.ROAD_FRAME_XY_SPEED, None],
            [sp.Matrix([sa]), ObservationKind.STEER_ANGLE, None],
            [
                sp.Matrix([angle_offset_fast]),
                ObservationKind.ANGLE_OFFSET_FAST, None
            ],
            [sp.Matrix([sR]), ObservationKind.STEER_RATIO, None],
            [sp.Matrix([x]), ObservationKind.STIFFNESS, None],
        ]

        gen_code(name,
                 f_sym,
                 dt,
                 state_sym,
                 obs_eqs,
                 dim_state,
                 dim_state,
                 maha_test_kinds=maha_test_kinds,
                 global_vars=CarKalman.global_vars)

    def __init__(self, steer_ratio=15, stiffness_factor=1, angle_offset=0):
        self.dim_state = self.x_initial.shape[0]
        x_init = self.x_initial
        x_init[States.STEER_RATIO] = steer_ratio
        x_init[States.STIFFNESS] = stiffness_factor
        x_init[States.ANGLE_OFFSET] = angle_offset

        # init filter
        self.filter = EKF_sym(self.name,
                              self.Q,
                              self.x_initial,
                              self.P_initial,
                              self.dim_state,
                              self.dim_state,
                              maha_test_kinds=self.maha_test_kinds,
                              global_vars=self.global_vars)

    @property
    def x(self):
        return self.filter.state()

    @property
    def P(self):
        return self.filter.covs()

    def predict(self, t):
        return self.filter.predict(t)

    def rts_smooth(self, estimates):
        return self.filter.rts_smooth(estimates, norm_quats=False)

    def get_R(self, kind, n):
        obs_noise = self.obs_noise[kind]
        dim = obs_noise.shape[0]
        R = np.zeros((n, dim, dim))
        for i in range(n):
            R[i, :, :] = obs_noise
        return R

    def init_state(self, state, covs_diag=None, covs=None, filter_time=None):
        if covs_diag is not None:
            P = np.diag(covs_diag)
        elif covs is not None:
            P = covs
        else:
            P = self.filter.covs()
        self.filter.init_state(state, P, filter_time)

    def predict_and_observe(self, t, kind, data, R=None):
        if len(data) > 0:
            data = np.atleast_2d(data)

        if R is None:
            R = self.get_R(kind, len(data))

        self.filter.predict_and_update_batch(t, kind, data, R)
Ejemplo n.º 8
0
class LiveKalman():
  name = 'live'

  initial_x = np.array([-2.7e6, 4.2e6, 3.8e6,
                        1, 0, 0, 0,
                        0, 0, 0,
                        0, 0, 0,
                        0, 0, 0,
                        1,
                        0, 0, 0,
                        0, 0, 0])

  # state covariance
  initial_P_diag = np.array([10000**2, 10000**2, 10000**2,
                             10**2, 10**2, 10**2,
                             10**2, 10**2, 10**2,
                             1**2, 1**2, 1**2,
                             0.05**2, 0.05**2, 0.05**2,
                             0.02**2,
                             1**2, 1**2, 1**2,
                             (0.01)**2, (0.01)**2, (0.01)**2])

  # process noise
  Q = np.diag([0.03**2, 0.03**2, 0.03**2,
               0.0**2, 0.0**2, 0.0**2,
               0.0**2, 0.0**2, 0.0**2,
               0.1**2, 0.1**2, 0.1**2,
               (0.005 / 100)**2, (0.005 / 100)**2, (0.005 / 100)**2,
               (0.02 / 100)**2,
               3**2, 3**2, 3**2,
               (0.05 / 60)**2, (0.05 / 60)**2, (0.05 / 60)**2])

  @staticmethod
  def generate_code():
    name = LiveKalman.name
    dim_state = LiveKalman.initial_x.shape[0]
    dim_state_err = LiveKalman.initial_P_diag.shape[0]

    state_sym = sp.MatrixSymbol('state', dim_state, 1)
    state = sp.Matrix(state_sym)
    x, y, z = state[States.ECEF_POS, :]
    q = state[States.ECEF_ORIENTATION, :]
    v = state[States.ECEF_VELOCITY, :]
    vx, vy, vz = v
    omega = state[States.ANGULAR_VELOCITY, :]
    vroll, vpitch, vyaw = omega
    roll_bias, pitch_bias, yaw_bias = state[States.GYRO_BIAS, :]
    odo_scale = state[States.ODO_SCALE, :][0,:]
    acceleration = state[States.ACCELERATION, :]
    imu_angles = state[States.IMU_OFFSET, :]

    dt = sp.Symbol('dt')

    # calibration and attitude rotation matrices
    quat_rot = quat_rotate(*q)

    # Got the quat predict equations from here
    # A New Quaternion-Based Kalman Filter for
    # Real-Time Attitude Estimation Using the Two-Step
    # Geometrically-Intuitive Correction Algorithm
    A = 0.5 * sp.Matrix([[0, -vroll, -vpitch, -vyaw],
                         [vroll, 0, vyaw, -vpitch],
                         [vpitch, -vyaw, 0, vroll],
                         [vyaw, vpitch, -vroll, 0]])
    q_dot = A * q

    # Time derivative of the state as a function of state
    state_dot = sp.Matrix(np.zeros((dim_state, 1)))
    state_dot[States.ECEF_POS, :] = v
    state_dot[States.ECEF_ORIENTATION, :] = q_dot
    state_dot[States.ECEF_VELOCITY, 0] = quat_rot * acceleration

    # Basic descretization, 1st order intergrator
    # Can be pretty bad if dt is big
    f_sym = state + dt * state_dot

    state_err_sym = sp.MatrixSymbol('state_err', dim_state_err, 1)
    state_err = sp.Matrix(state_err_sym)
    quat_err = state_err[States.ECEF_ORIENTATION_ERR, :]
    v_err = state_err[States.ECEF_VELOCITY_ERR, :]
    omega_err = state_err[States.ANGULAR_VELOCITY_ERR, :]
    acceleration_err = state_err[States.ACCELERATION_ERR, :]

    # Time derivative of the state error as a function of state error and state
    quat_err_matrix = euler_rotate(quat_err[0], quat_err[1], quat_err[2])
    q_err_dot = quat_err_matrix * quat_rot * (omega + omega_err)
    state_err_dot = sp.Matrix(np.zeros((dim_state_err, 1)))
    state_err_dot[States.ECEF_POS_ERR, :] = v_err
    state_err_dot[States.ECEF_ORIENTATION_ERR, :] = q_err_dot
    state_err_dot[States.ECEF_VELOCITY_ERR, :] = quat_err_matrix * quat_rot * (acceleration + acceleration_err)
    f_err_sym = state_err + dt * state_err_dot

    # Observation matrix modifier
    H_mod_sym = sp.Matrix(np.zeros((dim_state, dim_state_err)))
    H_mod_sym[States.ECEF_POS, States.ECEF_POS_ERR] = np.eye(States.ECEF_POS.stop - States.ECEF_POS.start)
    H_mod_sym[States.ECEF_ORIENTATION, States.ECEF_ORIENTATION_ERR] = 0.5 * quat_matrix_r(state[3:7])[:, 1:]
    H_mod_sym[States.ECEF_ORIENTATION.stop:, States.ECEF_ORIENTATION_ERR.stop:] = np.eye(dim_state - States.ECEF_ORIENTATION.stop)

    # these error functions are defined so that say there
    # is a nominal x and true x:
    # true x = err_function(nominal x, delta x)
    # delta x = inv_err_function(nominal x, true x)
    nom_x = sp.MatrixSymbol('nom_x', dim_state, 1)
    true_x = sp.MatrixSymbol('true_x', dim_state, 1)
    delta_x = sp.MatrixSymbol('delta_x', dim_state_err, 1)

    err_function_sym = sp.Matrix(np.zeros((dim_state, 1)))
    delta_quat = sp.Matrix(np.ones(4))
    delta_quat[1:, :] = sp.Matrix(0.5 * delta_x[States.ECEF_ORIENTATION_ERR, :])
    err_function_sym[States.ECEF_POS, :] = sp.Matrix(nom_x[States.ECEF_POS, :] + delta_x[States.ECEF_POS_ERR, :])
    err_function_sym[States.ECEF_ORIENTATION, 0] = quat_matrix_r(nom_x[States.ECEF_ORIENTATION, 0]) * delta_quat
    err_function_sym[States.ECEF_ORIENTATION.stop:, :] = sp.Matrix(nom_x[States.ECEF_ORIENTATION.stop:, :] + delta_x[States.ECEF_ORIENTATION_ERR.stop:, :])

    inv_err_function_sym = sp.Matrix(np.zeros((dim_state_err, 1)))
    inv_err_function_sym[States.ECEF_POS_ERR, 0] = sp.Matrix(-nom_x[States.ECEF_POS, 0] + true_x[States.ECEF_POS, 0])
    delta_quat = quat_matrix_r(nom_x[States.ECEF_ORIENTATION, 0]).T * true_x[States.ECEF_ORIENTATION, 0]
    inv_err_function_sym[States.ECEF_ORIENTATION_ERR, 0] = sp.Matrix(2 * delta_quat[1:])
    inv_err_function_sym[States.ECEF_ORIENTATION_ERR.stop:, 0] = sp.Matrix(-nom_x[States.ECEF_ORIENTATION.stop:, 0] + true_x[States.ECEF_ORIENTATION.stop:, 0])

    eskf_params = [[err_function_sym, nom_x, delta_x],
                   [inv_err_function_sym, nom_x, true_x],
                   H_mod_sym, f_err_sym, state_err_sym]
    #
    # Observation functions
    #
    imu_rot = euler_rotate(*imu_angles)
    h_gyro_sym = imu_rot * sp.Matrix([vroll + roll_bias,
                                      vpitch + pitch_bias,
                                      vyaw + yaw_bias])

    pos = sp.Matrix([x, y, z])
    gravity = quat_rot.T * ((EARTH_GM / ((x**2 + y**2 + z**2)**(3.0 / 2.0))) * pos)
    h_acc_sym = imu_rot * (gravity + acceleration)
    h_phone_rot_sym = sp.Matrix([vroll, vpitch, vyaw])

    speed = sp.sqrt(vx**2 + vy**2 + vz**2)
    h_speed_sym = sp.Matrix([speed * odo_scale])

    h_pos_sym = sp.Matrix([x, y, z])
    h_imu_frame_sym = sp.Matrix(imu_angles)

    h_relative_motion = sp.Matrix(quat_rot.T * v)

    obs_eqs = [[h_speed_sym, ObservationKind.ODOMETRIC_SPEED, None],
               [h_gyro_sym, ObservationKind.PHONE_GYRO, None],
               [h_phone_rot_sym, ObservationKind.NO_ROT, None],
               [h_acc_sym, ObservationKind.PHONE_ACCEL, None],
               [h_pos_sym, ObservationKind.ECEF_POS, None],
               [h_relative_motion, ObservationKind.CAMERA_ODO_TRANSLATION, None],
               [h_phone_rot_sym, ObservationKind.CAMERA_ODO_ROTATION, None],
               [h_imu_frame_sym, ObservationKind.IMU_FRAME, None]]

    gen_code(name, f_sym, dt, state_sym, obs_eqs, dim_state, dim_state_err, eskf_params)

  def __init__(self):
    self.dim_state = self.initial_x.shape[0]
    self.dim_state_err = self.initial_P_diag.shape[0]

    self.obs_noise = {ObservationKind.ODOMETRIC_SPEED: np.atleast_2d(0.2**2),
                      ObservationKind.PHONE_GYRO: np.diag([0.025**2, 0.025**2, 0.025**2]),
                      ObservationKind.PHONE_ACCEL: np.diag([.5**2, .5**2, .5**2]),
                      ObservationKind.CAMERA_ODO_ROTATION: np.diag([0.05**2, 0.05**2, 0.05**2]),
                      ObservationKind.IMU_FRAME: np.diag([0.05**2, 0.05**2, 0.05**2]),
                      ObservationKind.NO_ROT: np.diag([0.00025**2, 0.00025**2, 0.00025**2]),
                      ObservationKind.ECEF_POS: np.diag([5**2, 5**2, 5**2])}

    # init filter
    self.filter = EKF_sym(self.name, self.Q, self.initial_x, np.diag(self.initial_P_diag), self.dim_state, self.dim_state_err)

  @property
  def x(self):
    return self.filter.state()

  @property
  def t(self):
    return self.filter.filter_time

  @property
  def P(self):
    return self.filter.covs()

  def rts_smooth(self, estimates):
    return self.filter.rts_smooth(estimates, norm_quats=True)

  def init_state(self, state, covs_diag=None, covs=None, filter_time=None):
    if covs_diag is not None:
      P = np.diag(covs_diag)
    elif covs is not None:
      P = covs
    else:
      P = self.filter.covs()
    self.filter.init_state(state, P, filter_time)

  def predict_and_observe(self, t, kind, data):
    if len(data) > 0:
      data = np.atleast_2d(data)
    if kind == ObservationKind.CAMERA_ODO_TRANSLATION:
      r = self.predict_and_update_odo_trans(data, t, kind)
    elif kind == ObservationKind.CAMERA_ODO_ROTATION:
      r = self.predict_and_update_odo_rot(data, t, kind)
    elif kind == ObservationKind.ODOMETRIC_SPEED:
      r = self.predict_and_update_odo_speed(data, t, kind)
    else:
      r = self.filter.predict_and_update_batch(t, kind, data, self.get_R(kind, len(data)))

    # Normalize quats
    quat_norm = np.linalg.norm(self.filter.x[3:7, 0])

    # Should not continue if the quats behave this weirdly
    if not (0.1 < quat_norm < 10):
      raise KalmanError

    self.filter.x[States.ECEF_ORIENTATION, 0] = self.filter.x[States.ECEF_ORIENTATION, 0] / quat_norm

    return r

  def get_R(self, kind, n):
    obs_noise = self.obs_noise[kind]
    dim = obs_noise.shape[0]
    R = np.zeros((n, dim, dim))
    for i in range(n):
      R[i, :, :] = obs_noise
    return R

  def predict_and_update_odo_speed(self, speed, t, kind):
    z = np.array(speed)
    R = np.zeros((len(speed), 1, 1))
    for i, _ in enumerate(z):
      R[i, :, :] = np.diag([0.2**2])
    return self.filter.predict_and_update_batch(t, kind, z, R)

  def predict_and_update_odo_trans(self, trans, t, kind):
    z = trans[:, :3]
    R = np.zeros((len(trans), 3, 3))
    for i, _ in enumerate(z):
        R[i, :, :] = np.diag(trans[i, 3:]**2)
    return self.filter.predict_and_update_batch(t, kind, z, R)

  def predict_and_update_odo_rot(self, rot, t, kind):
    z = rot[:, :3]
    R = np.zeros((len(rot), 3, 3))
    for i, _ in enumerate(z):
        R[i, :, :] = np.diag(rot[i, 3:]**2)
    return self.filter.predict_and_update_batch(t, kind, z, R)