Exemple #1
0
    def __init__(self, num_ownship_states, x0, P0, buffer_capacity, meas_space_table, delta_codebook_table, delta_multipliers, asset2id, my_name, default_meas_variance):
        """Constructor

        Arguments:
            num_ownship_states {int} -- Number of ownship states for each asset
            x0 {np.ndarray} -- initial states
            P0 {np.ndarray} -- initial uncertainty
            buffer_capacity {int} -- capacity of measurement buffer
            meas_space_table {dict} -- Hash that stores how much buffer space a measurement takes up. Str (meas type) -> int (buffer space)
            delta_codebook_table {dict} -- Hash that stores delta trigger for each measurement type. Str(meas type) -> float (delta trigger)
            delta_multipliers {list} -- List of delta trigger multipliers
            asset2id {dict} -- Hash to get the id number of an asset from the string name
            my_name {str} -- Name to loopkup in asset2id the current asset's ID#
            default_meas_variance {dict} -- Hash to get measurement variance
        """
        self.meas_ledger = []
        self.asset2id = asset2id
        self.my_name = my_name
        self.default_meas_variance = default_meas_variance

        self.filter = ETFilter(asset2id[my_name], num_ownship_states, 3, x0, P0, True)

        # Remember for instantiating new LedgerFilters
        self.num_ownship_states = num_ownship_states
        self.buffer_capacity = buffer_capacity
        self.meas_space_table = meas_space_table
        self.last_update_time = None
Exemple #2
0
    def __init__(self,
                 num_ownship_states,
                 x0,
                 P0,
                 delta_codebook_table,
                 delta_multiplier,
                 is_main_filter,
                 asset2id,
                 my_name,
                 default_meas_variance,
                 common_filter=None):
        """Constructor

        Arguments:
            num_ownship_states {int} -- Number of ownship states for each asset
            x0 {np.ndarray} -- initial states
            P0 {np.ndarray} -- initial uncertainty
            delta_codebook_table {dict} -- Hash thatp stores delta trigger for each measurement type. Str(meas type) -> float (delta trigger)
            delta_multiplier {float} -- Delta trigger constant multiplier for this filter
            is_main_filter {bool} -- Is this filter a common or main filter (if main the meas buffer does not matter)
            asset2id {dict} -- Hash to get the id number of an asset from the string name
            my_name {str} -- Name to loopkup in asset2id the current asset's ID#
            default_meas_variance {dict} -- Hash to get measurement variance
            common_filter {dict} -- asset to common ETFilter
        """
        if delta_multiplier <= 0:
            raise ValueError("Delta Multiplier must be greater than 0")

        self.num_ownship_states = num_ownship_states
        self.delta_codebook_table = delta_codebook_table
        self.delta_multiplier = delta_multiplier
        self.is_main_filter = is_main_filter
        if self.is_main_filter:
            assert common_filter is not None
            self.filter = ETFilter_Main(asset2id[my_name], num_ownship_states,
                                        3, x0, P0, True, {"": common_filter})
        else:
            self.filter = ETFilter(asset2id[my_name], num_ownship_states, 3,
                                   x0, P0, True)
        self.original_filter = deepcopy(self.filter)
        self.asset2id = asset2id
        self.my_name = my_name
        self.default_meas_variance = default_meas_variance

        # Initialize ledger with first update
        self.ledger = {}
        self._add_block()

        self.explicit_count = 0
        self.meas_types_received = []
    def __init__(self, num_ownship_states, x0, P0, buffer_capacity,
                 meas_space_table, missed_meas_tolerance_table,
                 delta_codebook_table, delta_multiplier, is_main_filter,
                 my_id):
        """Constructor

        Arguments:
            num_ownship_states {int} -- Number of ownship states for each asset
            x0 {np.ndarray} -- initial states
            P0 {np.ndarray} -- initial uncertainty
            buffer_capacity {int} -- capacity of measurement buffer
            meas_space_table {dict} -- Hash that stores how much buffer space a measurement takes up. Str (meas type) -> int (buffer space)
                Must have key entries "bookend", "bookstart" to indicate space needed for measurement implicitness filling in
            missed_meas_tolerance_table {dict} -- Hash that determines how many measurements of each type do we need to miss before indicating a bookend
            delta_codebook_table {dict} -- Hash thatp stores delta trigger for each measurement type. Str(meas type) -> float (delta trigger)
            delta_multiplier {float} -- Delta trigger constant multiplier for this filter
            is_main_filter {bool} -- Is this filter a common or main filter (if main the meas buffer does not matter)
            my_id {int} -- ID# of the current asset (typically 0)
        """
        if delta_multiplier <= 0:
            raise ValueError("Delta Multiplier must be greater than 0")

        self.original_estimate = [deepcopy(x0), deepcopy(P0)]
        self.delta_codebook_table = delta_codebook_table
        self.delta_multiplier = delta_multiplier
        self.buffer = MeasurementBuffer(meas_space_table, buffer_capacity)
        self.missed_meas_tolerance_table = missed_meas_tolerance_table
        self.is_main_filter = is_main_filter
        self.filter = ETFilter(my_id, num_ownship_states, 3, x0, P0, True)

        # Initialize Ledgers
        self.ledger_meas = []  # In internal measurement form
        self.ledger_control = [
        ]  ## elements with [u, Q, time_delta, use_control_input]
        self.ledger_ci = [
        ]  ## Covariance Intersection ledger, each element is of form [x, P]
        self.ledger_update_times = [
        ]  ## Update times of when correction step executed
        self.expected_measurements = {
        }  # When we don't receive an expected measurement we need to insert a "bookend" into the measurement buffer

        # Initialize first element of ledgers
        self.ledger_meas.append([])
        self.ledger_control.append([])
        self.ledger_ci.append([])
Exemple #4
0
    def catch_up(self, delta_multiplier, shared_buffer):
        """Updates main estimate and common estimate using the shared buffer

        Arguments:
            delta_multiplier {float} -- multiplier to scale et_delta's with
            shared_buffer {list} -- buffer shared from another asset
        Returns:
            int -- implicit measurement count in shared_buffer
            int -- explicit measurement count in this shared_buffer
        """
        # Fill in implicit measurements in the buffer and align the meas timestamps with our own
        new_buffer, next_ledger_time_index = self._fillin_buffer(shared_buffer)
        implicit_meas_cnt = 0
        explicit_meas_cnt = 0

        # Add all measurements in buffer to ledgers of all ledger_filters
        for meas in new_buffer:
            self.add_meas(meas, delta_multiplier, force_fuse=False)
            if "implicit" in meas.meas_type:
                implicit_meas_cnt += 1
            else:
                explicit_meas_cnt += 1

        common_filters = {}
        for mult in self.delta_tiers.keys():
            my_id = self.delta_tiers[mult].filter.my_id
            [x0, P0] = self.delta_tiers[mult].original_estimate
            common_filters[mult] = ETFilter(my_id, self.num_ownship_states, 3,
                                            x0, P0, True)

        # Initialize asset's main filter
        # Pair the main filter with the etfilter the other asset chose and use to update the main filter
        my_id = self.main_filter.filter.my_id
        [x0, P0] = self.main_filter.original_estimate
        other_assets_common = {my_id: common_filters[delta_multiplier]}
        main_filter = ETFilter_Main(my_id, self.num_ownship_states, 3, x0, P0,
                                    True, other_assets_common)

        # Extract full ledgers
        common_meas_ledger = {}
        for mult in self.delta_tiers.keys():
            common_meas_ledger[mult] = self.delta_tiers[mult].ledger_meas
        main_control_ledger = self.main_filter.ledger_control
        main_ledger_meas = self.main_filter.ledger_meas
        # TODO add covariance intersection support (happens before correction)
        main_ci_ledger = self.main_filter.ledger_meas

        # Grab lock, no updates for right now
        # Initialize a new main and common filters (all are etfilters) using original estimate
        for i_ledge in range(len(self.main_filter.ledger_update_times)):

            [u, Q, delta_time, _] = main_control_ledger[i_ledge]

            for mult in common_filters.keys():
                common_filters[mult].predict(u,
                                             Q,
                                             delta_time,
                                             use_control_input=False)
                ledger_meas = common_meas_ledger[mult][i_ledge]
                for meas in ledger_meas:
                    common_filters[mult].add_meas(meas)
                common_filters[mult].correct()

            main_filter.predict(u, Q, delta_time, use_control_input=True)
            for meas in main_ledger_meas[i_ledge]:
                main_filter.add_meas(meas)
            main_filter.correct()

        # Trim ledgers
        if next_ledger_time_index != len(self.main_filter.ledger_update_times):
            ledger_update_times = self.main_filter.ledger_update_times[
                next_ledger_time_index:]
            for mult in common_meas_ledger.keys():
                common_meas_ledger[mult] = common_meas_ledger[mult][
                    next_ledger_time_index:]
            main_ledger_meas = main_ledger_meas[next_ledger_time_index:]
            main_control_ledger = main_control_ledger[next_ledger_time_index:]
        else:
            ledger_update_times = []
            for mult in common_meas_ledger.keys():
                common_meas_ledger[mult] = [[]]
            main_ledger_meas = [[]]
            main_control_ledger = [[]]

        ### Reset the ledger filters ###

        # Reset the delta tier filters
        for multiplier in self.delta_tiers.keys():

            # Caught up estimate becomes new initial estimate
            x0 = common_filters[multiplier].x_hat
            P0 = common_filters[multiplier].P

            buf = deepcopy(self.delta_tiers[multiplier].buffer)
            # Instantiate new delta tier
            self.delta_tiers[multiplier] = LedgerFilter(
                self.num_ownship_states, x0, P0, \
                self.buffer_capacity, self.meas_space_table, \
                self.missed_meas_tolerance_table, \
                self.delta_codebook_table, multiplier, \
                False, self.asset2id[self.my_name]
            )
            self.delta_tiers[multiplier].reset(buf, ledger_update_times,
                                               common_meas_ledger[multiplier])

        ### Reset the main filter ###

        # Caught up estimate becomes new initial estimate
        x0 = main_filter.x_hat
        P0 = main_filter.P
        mainbuf = deepcopy(self.main_filter.buffer)
        # Instantiate new Main Filter
        self.main_filter = LedgerFilter(
            self.num_ownship_states, x0, P0, \
            self.buffer_capacity, self.meas_space_table, \
            self.missed_meas_tolerance_table, \
            self.delta_codebook_table, 1.0, \
            True, self.asset2id[self.my_name]
        )
        self.main_filter.reset(mainbuf, ledger_update_times, main_ledger_meas,
                               main_control_ledger)

        return implicit_meas_cnt, explicit_meas_cnt