Esempio n. 1
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    def on_first_run(self, slide_direction="right", *args, **kwargs):
        self.logi("Starting UncoverBin task")
        self.init_time = self.this_run_time

        if slide_direction == "right":
          factor = 1
        elif slide_direction == "left":
          factor = -1
        else:
          raise Exception("Invalid slide direction %s for UncoverBin" % slide_direction)

        self.initial_depth = shm.kalman.depth.get()
        self.set_depth = Depth(self.initial_depth + shm.dvl.savg_altitude.get() - BINS_PICKUP_ALTITUDE, deadband=0.01)
        self.initial_position = get_sub_position()

        self.pickup = MasterConcurrent(Sequential(Timer(2.0), Roll(-30 * factor, error=90)), VelocityY(1.0 * factor))
        self.drop = Sequential(Roll(90 * factor), Timer(1.0), Roll(120 * factor, error=40), Timer(0.5), Roll(90 * factor),
                               Timer(0.3), Roll(45 * factor), Timer(0.5), Roll(0))
        #self.return_to_bin = GoToPosition(lambda: self.initial_position[0], lambda: self.initial_position[1], depth=self.initial_depth)
        self.return_to_bin = Sequential(Timed(VelocityY(-1.0 * factor), 2.0), VelocityY(0.0), MoveX(-BINS_CAM_TO_ARM_OFFSET))
        self.tasks = Sequential(
                       MoveY(-0.65 * factor),
                       MoveX(BINS_CAM_TO_ARM_OFFSET),
                       self.set_depth,
                       Roll(60 * factor),
                       self.pickup,
                       VelocityY(0.0),
                       RelativeToInitialDepth(-1.0),
                       Timed(VelocityY(1.0 * factor), 1.0),
                       VelocityY(0.0),
                       self.drop,
                       Timed(VelocityY(-1.0 * factor), 1.0),
                       self.return_to_bin
                     )
Esempio n. 2
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  def func(watcher, quit_event):
    watcher.watch(shm.hydrophones_results_track)

    observations = []

    localizer = Localizer(shm.hydrophones_settings.track_frequency_target.get())

    while not quit_event.is_set():
      #input()
      results = shm.hydrophones_results_track.get()
      kalman = shm.kalman.get()

      sub_pos = get_sub_position(kalman)
      sub_quat = get_sub_quaternion(kalman)

      print("------------------------------------------------------")
      localizer.add_observation((results.diff_phase_x, results.diff_phase_y), sub_pos, sub_quat)

      pinger_pos, pinger_pos_all = localizer.compute_position()

      print("%d observations. current position: %0.2f %0.2f %0.2f" % \
            (len(localizer.observations), sub_pos[0], sub_pos[1], sub_pos[2]))
      print("Predicted (2 Trans): %0.2f %0.2f %0.2f" % \
            (pinger_pos[0], pinger_pos[1], pinger_pos[2]))
      print("Predicted (3 Trans): %0.2f %0.2f %0.2f" % \
            (pinger_pos_all[0], pinger_pos_all[1], pinger_pos_all[2]))

      watcher.wait(new_update=False)
Esempio n. 3
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    def func(watcher, quit_event):
        watcher.watch(shm.hydrophones_results_track)

        observations = []

        localizer = Localizer(
            shm.hydrophones_settings.track_frequency_target.get())

        while not quit_event.is_set():
            # input()
            results = shm.hydrophones_results_track.get()
            kalman = shm.kalman.get()

            sub_pos = get_sub_position(kalman)
            sub_quat = get_sub_quaternion(kalman)

            print("------------------------------------------------------")
            localizer.add_observation(
                (results.diff_phase_x, results.diff_phase_y), sub_pos,
                sub_quat)

            pinger_pos, pinger_pos_all = localizer.compute_position()

            print("%d observations. current position: %0.2f %0.2f %0.2f" % \
                  (len(localizer.observations), sub_pos[0], sub_pos[1], sub_pos[2]))
            print("Predicted (2 Trans): %0.2f %0.2f %0.2f" % \
                  (pinger_pos[0], pinger_pos[1], pinger_pos[2]))
            print("Predicted (3 Trans): %0.2f %0.2f %0.2f" % \
                  (pinger_pos_all[0], pinger_pos_all[1], pinger_pos_all[2]))

            watcher.wait(new_update=False)
Esempio n. 4
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    def collision_validator(self):
        # TODO even more robust collision validator
        current = yellow_buoy_results.percent_frame.get()

        aligned = self.concurrent_align_task.finished
        max_ram_speed = self.MAX_RAM_SPEED
        if not aligned:
          max_ram_speed /= 3

        self.ram_speed = scaled_speed(final_value=self.PERCENT_FRAME_THRESHOLD + 1,
                                      initial_value=self.PERCENT_FRAME_SLOWDOWN_THRESHOLD,
                                      final_speed=0.0, initial_speed=max_ram_speed,
                                      current_value=current)

        if self.ready_to_ram_checker.check(current >= self.PERCENT_FRAME_THRESHOLD and \
                                           aligned):
            self.target_position = get_sub_position()
            self.target_depth = shm.kalman.depth.get()
            self.logi("Close enough to yellow buoy to scuttle!")
            return True
            #if yellow_buoy_results.center_y.get() > (shm.camera.forward_height.get() - 10) \
            #   and abs(self.last_percent_frame - current) <= self.PERCENT_FRAME_DELTA_THRESHOLD:
            #    return True
            #self.last_percent_frame = current
        return False
Esempio n. 5
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  def on_first_run(self):
    shm.hydrophones_settings.track_frequency_target.set(PINGER_FREQUENCY)
    shm.hydrophones_settings.track_magnitude_threshold.set(TRACK_MAG_THRESH)
    shm.hydrophones_settings.track_cooldown_samples.set(150000)

    shm.navigation_settings.position_controls.set(1)
    shm.navigation_settings.optimize.set(0)

    self.localizer = Localizer(PINGER_FREQUENCY)

    self.hydro_watcher = shm.watchers.watcher()
    self.hydro_watcher.watch(shm.hydrophones_results_track)

    self.time_since_last_ping = self.this_run_time

    self.pinger_positions = collections.deque(maxlen=7)

    self.PINGS_LISTEN = 10
    self.CONSISTENT_PINGS = 3

    self.listens = 0
    self.queued_moves = []
    self.pinger_found = False

    self.silencer = ThrusterSilencer()

    self.available_depths = set([HYDROPHONES_SEARCH_DEPTH,
                                 HYDROPHONES_SEARCH_DEPTH + 0.4,
                                 HYDROPHONES_SEARCH_DEPTH + 0.2])
    self.last_depth = None

    self.elevation_checker = ConsistencyCheck(3, 3)

    self.observe_from(get_sub_position())
Esempio n. 6
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    def update_pings(self):
        self.silencer()

        # TODO Better way to filter out bad pings when thrusters are running.
        # If the watcher has not changed, there is no new ping
        if not self.hydro_watcher.has_changed():
            # TODO Do something here if too much time has passed since last ping.
            return None
        # There is a new ping!

        self.time_since_last_ping = self.this_run_time

        # TODO Will this be long after the watcher fired?
        # Need to ensure that there is little delay.
        results = shm.hydrophones_results_track.get()
        kalman = shm.kalman.get()

        phases = (results.diff_phase_x, results.diff_phase_y)

        if not self.localizer.is_valid(phases[0], phases[1]):
            self.logi("Warning: Measured phases (%0.3f %0.3f) are not possible given "
                      "physical parameters" % \
                      (phases[0], phases[1]))

        head, elev = self.localizer.get_heading_elevation(*phases)
        abs_head = (head + shm.kalman.heading.get()) % 360
        self.logi("Ping: Phases: (%0.3f %0.3f), Relative Heading: %0.5f, Absolute "
                  "Heading: %0.3f, Elevation: %0.1f" % \
                  (phases[0], phases[1], head, abs_head, elev))

        in_silence = self.silencer.in_silence()

        # TODO Better way to detect ping period.
        this_ping_time = \
            results.daemon_start_time + results.tracked_ping_time
        self.silencer.schedule_silence(this_ping_time + PINGER_PERIOD - 0.2,
                                       3.0)

        self.logi("This time: %0.3f, This ping time %0.3f, Diff: %0.3f" %
                  (self.this_run_time, this_ping_time,
                   self.this_run_time - this_ping_time))

        # If the thrusters are not in silence, then we may have heard thruster
        # noise and thought it was a ping; ignore it
        if not in_silence:
            self.logi("Heard ping but thrusters are not silenced, ignoring")
            return None

        # Record ping data
        sub_pos = get_sub_position(kalman)
        sub_quat = get_sub_quaternion(kalman)
        ping_data = PingData(phases, head, elev, sub_pos, sub_quat)
        self.pings.append(ping_data)

        return ping_data
Esempio n. 7
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    def on_first_run(self, slide_direction="right", *args, **kwargs):
        self.logi("Starting UncoverBin task")
        self.init_time = self.this_run_time

        if slide_direction == "right":
          factor = 1
        elif slide_direction == "left":
          factor = -1
        else:
          raise Exception("Invalid slide direction %s for UncoverBin" % slide_direction)

        self.initial_depth = shm.kalman.depth.get()
        pool_depth = get_pool_depth(self.logw, self.initial_depth)

        self.set_depth = Timeout(Depth(pool_depth - BINS_PICKUP_ALTITUDE, deadband=0.01), 15)
        self.initial_position = get_sub_position()

        SLIDE_SPEED = 0.35
        self.pickup = MasterConcurrent(Sequential(Timer(0.7 * 6), Roll(0, error=90), Timer(0.3 * 2),
                                       Timed(Concurrent(RelativeToCurrentDepth(-2.0), Roll(-15 * factor, error=90)), 2.0 * 1),
                                       RelativeToCurrentDepth(0, error=2), Roll(-30 * factor, error=90)), VelocityY(SLIDE_SPEED * factor))
        self.drop = Sequential(Roll(90 * factor, error=20), Timer(1.0), Roll(120 * factor, error=40), Timer(0.5), Roll(90 * factor, error=20),
                               Timer(0.3), Roll(45 * factor), Timer(0.5), Roll(0))
        #self.return_to_bin = GoToPosition(lambda: self.initial_position[0], lambda: self.initial_position[1], depth=self.initial_depth)
        self.return_to_bin = Sequential(Timed(VelocityY(-1.0 * factor), 1.8), VelocityY(0.0),
                                        Timeout(MoveX(-BINS_CAM_TO_ARM_OFFSET, deadband=0.03), 10))
        self.tasks = Sequential(
                       Timeout(MoveY(-0.85 * factor, deadband=0.025), 10),
                       Timeout(MoveX(BINS_CAM_TO_ARM_OFFSET, deadband=0.015), 10),
                       self.set_depth,
                       Roll(60 * factor, error=20),
                       self.pickup,
                       VelocityY(0.0),
                       RelativeToInitialDepth(-0.4, error=2),
                       Timed(VelocityY(1.0 * factor), 1.0),
                       VelocityY(0.0),
                       self.drop,
                       Timed(VelocityY(-1.0 * factor), 1.0),
                       self.return_to_bin
                     )
Esempio n. 8
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def downward_position(camera_position=(0, 0)):
    """
    distance = (objsize) * (camsize) / (image size * tan(theta)

    very similar to distance_from_size
    """

    # TODO: add pitch and roll compensation

    pos = get_sub_position()[:2]
    altitude = shm.dvl.savg_altitude.get()

    heading_rad = radians(shm.kalman.heading.get())
    heading_v = numpy.array((cos(heading_rad), sin(heading_rad)))
    heading_yv = numpy.array((-heading_v[1], heading_v[0]))

    screen_width = shm.camera.downward_width.get()
    screen_height = shm.camera.downward_height.get()
    screen_area = screen_width * screen_height
    if screen_area == 0:
        return numpy.array((0, 0))

    from locator.camera import compute_fov_from_lens_params, DOWNWARD_LENS_PARAMS
    h_fov, v_fov = compute_fov_from_lens_params(*DOWNWARD_LENS_PARAMS)

    max_angle_x = 2 * tan(h_fov / 2)
    max_angle_y = 2 * tan(v_fov / 2)

    camera_x, camera_y = camera_position
    camera_x -= .5 * screen_width
    camera_y -= .5 * screen_height

    x_scale = (camera_x / screen_width) * max_angle_x
    y_scale = (camera_y / screen_height) * max_angle_y

    x_distance = -1 * altitude * y_scale
    y_distance = altitude * x_scale

    return pos + (x_distance * heading_v) + (y_distance * heading_yv)
Esempio n. 9
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def downward_position(camera_position=(0, 0)):
    """
    distance = (objsize) * (camsize) / (image size * tan(theta)

    very similar to distance_from_size
    """

    # TODO: add pitch and roll compensation

    pos = get_sub_position()[:2]
    altitude = shm.dvl.savg_altitude.get()

    heading_rad = radians(shm.kalman.heading.get())
    heading_v = numpy.array((cos(heading_rad), sin(heading_rad)))
    heading_yv = numpy.array((-heading_v[1], heading_v[0]))

    screen_width = shm.camera.downward_width.get()
    screen_height = shm.camera.downward_height.get()
    screen_area = screen_width * screen_height
    if screen_area == 0:
        return numpy.array((0, 0))

    from locator.camera import compute_fov_from_lens_params, DOWNWARD_LENS_PARAMS
    h_fov, v_fov = compute_fov_from_lens_params(*DOWNWARD_LENS_PARAMS)

    max_angle_x = 2 * tan(h_fov / 2)
    max_angle_y = 2 * tan(v_fov / 2)

    camera_x, camera_y = camera_position
    camera_x -= .5 * screen_width
    camera_y -= .5 * screen_height

    x_scale = (camera_x / screen_width) * max_angle_x
    y_scale = (camera_y / screen_height) * max_angle_y

    x_distance = -1 * altitude * y_scale
    y_distance = altitude * x_scale

    return pos + (x_distance * heading_v) + (y_distance * heading_yv)
Esempio n. 10
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  def on_run(self):
    self.motion_tasks()

    self.silencer()

    # TODO Better way to filter out bad pings when thrusters are running.
    if not self.hydro_watcher.has_changed() or \
       (not LISTEN_WHILE_MOVING and not self.motion_tasks.finished):
      # TODO Do something here if too much time has passed since last ping.
      return

    if self.pinger_found:
      self.finish()
      return

    self.time_since_last_ping = self.this_run_time
    self.pings_here += 1

    # TODO Will this be long after the watcher fired?
    # Need to ensure that there is little delay.
    results = shm.hydrophones_results_track.get()
    kalman = shm.kalman.get()

    phases = (results.diff_phase_x, results.diff_phase_y)
    self.logi("Got " + str(phases))

    in_silence = self.silencer.in_silence()

    # TODO Better way to detect ping period.
    self.silencer.schedule_silence(self.this_run_time + PINGER_PERIOD - 0.1, 0.4)

    if not in_silence:
      return

    sub_pos = get_sub_position(kalman)
    sub_quat = get_sub_quaternion(kalman)
    ping_data = PingData(phases, sub_pos, sub_quat)
    self.pings.append(ping_data)

    if len(self.pings) < 2:
      return

    if not CLUSTER_HEADINGS:
      data = get_clusterable([ping.phases[0] for ping in self.pings])
      clusters = fclusterdata(data, 0.3, criterion="distance")
    else:
      headings, elevations = zip(*[self.localizer.get_heading_elevation(*ping.phases) for ping in self.pings])
      data = get_clusterable(headings)
      clusters = fclusterdata(data, 8, criterion="distance")

    counted = collections.Counter(clusters)

    best_cluster, n_best = max(counted.items(), key=lambda item: item[1])
    if n_best >= self.CONSISTENT_PINGS:
      good_pings = [self.pings[i] for i, cluster_num in enumerate(clusters) \
                    if cluster_num == best_cluster]
      avg_phase_x = np.mean([ping.phases[0] for ping in good_pings])
      avg_phase_y = np.mean([ping.phases[1] for ping in good_pings])

      self.logi("Found nice phases (%f, %f) in %s" % \
                (avg_phase_x, avg_phase_y, str(self.pings)))

      for ping in good_pings:
        self.localizer.add_observation(ping.phases, ping.sub_pos, ping.sub_quat)

      est_pinger_pos = self.localizer.compute_position()[USE_THREE]
      self.pinger_positions.append(est_pinger_pos)

      self.logi("We think the pinger is at %s" % str(est_pinger_pos))
      self.logi("All estimated positions: %s" % str(self.pinger_positions))

      if len(self.pinger_positions) > 5:
        data = np.array(self.pinger_positions)
        clusters = fclusterdata(data, 0.6, criterion="distance")
        counted = collections.Counter(clusters)
        best_cluster, n_best = max(counted.items(), key=lambda item: item[1])
        if n_best >= 3:
          avg_position = sum([np.array(self.pinger_positions[i]) for i, cluster_num in enumerate(clusters) if cluster_num == best_cluster]) / n_best
          self.logi("Found pinger at %0.2f %0.2f using localization!" % \
                    (avg_position[0], avg_position[1]))
          self.observe_from(avg_position)
          self.pinger_found = True
          return

      if FOLLOW_HEADING:
        heading, elevation = self.localizer.get_heading_elevation(avg_phase_x, avg_phase_y)

        depth_distance = HYDROPHONES_PINGER_DEPTH - kalman.depth
        distance = math.tan(math.radians(elevation)) * depth_distance

        # Elevations seem to be wrong; nerf them.
        distance = min(0.5 * distance, 4.2)

        direction = rotate((1, 0), kalman.heading + heading)
        observe_position = sub_pos + np.array((direction[0], direction[1], sub_pos[2])) * distance
        self.logi("Heading is %f, Elevation is %f" % (heading, elevation))
        self.observe_from(observe_position, kalman.heading + heading)

        if self.elevation_checker(elevation < 25):
          self.logi("Found pinger using elevations!")
          self.pinger_found = True

      elif not FOLLOW_HEADING:
        if self.listens <= 3:
          # TODO Change heading in an optimal fashion.
          self.observe_from(sub_pos, heading=(kalman.heading + 30) % 360)
        else:
          if not self.queued_moves:
            to_pinger = est_pinger_pos[:2] - sub_pos[:2]
            distance = np.linalg.norm(to_pinger)
            direction = to_pinger / distance

            move_dist = 3
            if self.listens > 10 and distance < 3:
              move_dist = distance

            new_pos = sub_pos[:2] + direction * move_dist
            heading = math.atan2(direction[1], direction[0])

            if DO_PARALLAX:
              perp = np.array(rotate(direction, 90))
              self.queued_moves.extend([(new_pos, heading), (new_pos + 2 * perp, heading), (new_pos - 2 * perp, heading)])

            else:
              if PERP_TO_PINGER:
                heading += 90
              self.queued_moves.extend([(new_pos, heading+30), (new_pos, heading-30), (new_pos, heading)])

          next_pos, heading = self.queued_moves.pop(0)
          self.observe_from(next_pos, heading)
Esempio n. 11
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  def on_run(self):
    self.motion_tasks()

    self.silencer()

    # TODO Better way to filter out bad pings when thrusters are running.
    if not self.hydro_watcher.has_changed() or \
       not self.motion_tasks.finished:
      # TODO Do something here if too much time has passed since last ping.
      return

    if self.pinger_found:
      self.finish()
      return

    self.time_since_last_ping = self.this_run_time
    self.pings_here += 1

    # TODO Will this be long after the watcher fired?
    # Need to ensure that there is little delay.
    results = shm.hydrophones_results_track.get()
    kalman = shm.kalman.get()

    phases = (results.diff_phase_x, results.diff_phase_y)
    self.logi("Got " + str(phases))

    in_silence = self.silencer.in_silence()

    self.silencer.schedule_silence(self.this_run_time + 0.9, 0.4)

    if not in_silence:
      return

    self.pings.append(results.diff_phase_x)

    if len(self.pings) < 2:
      return

    data = get_clusterable(self.pings)
    clusters = fclusterdata(data, 0.1, criterion="distance")
    counted = collections.Counter(clusters)

    best_cluster, n_best = max(counted.items(), key=lambda item: item[1])
    if n_best >= self.CONSISTENT_PINGS:
      avg_phase = sum([self.pings[i] for i, cluster_num in enumerate(clusters) if cluster_num == best_cluster]) / n_best

      self.logi("Found nice phase %f in %s" % (avg_phase, str(self.pings)))

      if FOLLOW_HEADING:
        # TODO Use average x and y phases here.
        heading, elevation = self.localizer.get_heading_elevation(*phases)

        if elevation > 45:
          move_distance = 4
        elif elevation > 30:
          move_distance = 2
        else:
          move_distance = 1

        sub_pos = get_sub_position(kalman)
        direction = rotate((1, 0), kalman.heading + heading)
        observe_position = sub_pos + np.array((direction[0], direction[1], sub_pos[2])) * move_distance
        self.logi("Heading is %f, Elevation is %f" % (heading, elevation))
        self.observe_from(observe_position, kalman.heading + heading)

      elif not FOLLOW_HEADING:
        sub_pos = get_sub_position(kalman)
        sub_quat = get_sub_quaternion(kalman)

        self.localizer.add_observation(phases, sub_pos, sub_quat)

        # For now, use the estimate from only 2 transducers.
        est_pinger_pos = self.localizer.compute_position()[USE_THREE]
        self.pinger_positions.append(est_pinger_pos)

        self.logi("We think the pinger is at %s" % str(est_pinger_pos))
        self.logi("All estimated positions: %s" % str(self.pinger_positions))

        if len(self.pinger_positions) > 5:
          data = np.array(self.pinger_positions)
          clusters = fclusterdata(data, 0.5, criterion="distance")
          counted = collections.Counter(clusters)
          best_cluster, n_best = max(counted.items(), key=lambda item: item[1])
          if n_best > 3:
            avg_position = sum([np.array(self.pinger_positions[i]) for i, cluster_num in enumerate(clusters) if cluster_num == best_cluster]) / n_best
            self.logi("Found pinger at %0.2f %0.2f!" % (avg_position[0], avg_position[1]))
            self.observe_from(avg_position)
            self.pinger_found = True
            return

        if self.listens <= 3:
          # TODO Change heading in an optimal fashion.
          self.observe_from(sub_pos, heading=(kalman.heading + 30) % 360)
        else:
          if not self.queued_moves:
            to_pinger = est_pinger_pos[:2] - sub_pos[:2]
            distance = np.linalg.norm(to_pinger)
            direction = to_pinger / distance

            move_dist = 3
            if self.listens > 10 and distance < 3:
              move_dist = distance

            new_pos = sub_pos[:2] + direction * move_dist
            heading = math.atan2(direction[1], direction[0])

            if DO_PARALLAX:
              perp = np.array(rotate(direction, 90))
              self.queued_moves.extend([(new_pos, heading), (new_pos + 2 * perp, heading), (new_pos - 2 * perp, heading)])

            else:
              if PERP_TO_PINGER:
                heading += 90
              self.queued_moves.extend([(new_pos, heading+30), (new_pos, heading-30), (new_pos, heading)])

          next_pos, heading = self.queued_moves.pop(0)
          self.observe_from(next_pos, heading)
Esempio n. 12
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PINGER_INTERVAL = 2.0

SOUND_SPEED = 1481.0

NIPPLE_DISTANCE = 0.013

PHASE2RATIO = SOUND_SPEED / (2 * math.pi * PINGER_FREQUENCY * NIPPLE_DISTANCE)

hydro_shm = shm.hydrophones_results_track

# Vector in body frame between first and second transducers.
trans_vec = np.array((1, 0, 0))
trans_vec2 = np.array((0, -1, 0))

while 1:
  kalman = shm.kalman.get()

  sub_pos = get_sub_position(kalman)
  sub_quat = get_sub_quaternion(kalman)
  trans_deltas = (sub_quat * trans_vec, sub_quat * trans_vec2)

  ratios = misc.hydro2trans.h(PINGER_POSITION, sub_pos, trans_deltas)
  phases = [ratio / PHASE2RATIO for ratio in ratios]

  hydro_group = hydro_shm.get()
  hydro_group.diff_phase_x = phases[0]
  hydro_group.diff_phase_y = phases[1]
  hydro_shm.set(hydro_group)

  time.sleep(PINGER_INTERVAL)
Esempio n. 13
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# Vector in body frame between first and second transducers.
trans_vec = np.array((1, 0, 0))
trans_vec2 = np.array((0, -1, 0))

start_time = time.time()
daemon_start_time = int(start_time)

# Turn off the default Python ^C handler that raises a KeyboardInterrupt.
# Now SIGINT should behave identically to SIGTERM: kill the program.
import signal
signal.signal(signal.SIGINT, signal.SIG_DFL)

while True:
    kalman = shm.kalman.get()

    sub_pos = get_sub_position(kalman)
    sub_quat = get_sub_quaternion(kalman)
    trans_deltas = (sub_quat * trans_vec, sub_quat * trans_vec2)

    ratios = misc.hydro2trans.h(PINGER_POSITION, sub_pos, trans_deltas)
    phases = [ratio / PHASE2RATIO for ratio in ratios]

    hydro_group = hydro_shm.get()
    hydro_group.diff_phase_x = phases[0]
    hydro_group.diff_phase_y = phases[1]
    hydro_group.ping_clock = 0 if hydro_group.ping_clock else 1
    hydro_group.daemon_start_time = daemon_start_time
    hydro_group.tracked_ping_time = time.time() - daemon_start_time
    hydro_shm.set(hydro_group)

    time.sleep(PINGER_INTERVAL -