viability

Functions

elevation_angle_viability(link_end_id, ...)

Function for defining single elevation angle viability setting.

body_avoidance_viability(link_end_id, ...)

Function for defining body avoidance observation viability settings.

body_occultation_viability(link_end_id, ...)

Function for defining body occultation viability settings.

elevation_angle_viability_list(link_end_ids, ...)

Function for defining list of elevation angle viability settings.

body_avoidance_viability_list(link_end_ids, ...)

Function for defining list of body avoidance viability settings.

body_occultation_viability_list(...)

Function for defining body occultation viability settings.

add_viability_check_to_all(...)

Function for including viability checks into existing observation simulation settings.

add_viability_check_to_observable(...)

Function for including viability checks into existing observation simulation settings.

add_viability_check_to_observable_for_link_ends(...)

Function for including viability checks into existing observation simulation settings.
elevation_angle_viability(link_end_id: tuple[str, str], elevation_angle: SupportsFloat) → tudatpy.kernel.estimation.observations_setup.viability.ObservationViabilitySettings

Function for defining single elevation angle viability setting.

Function for defining elevation angle viability settings for single link end. When simulating observations, this setting ensures that any applicable observations, for which the local elevation angle at link end is less than some limit value, will be omitted.

Parameters:

  • link_end_id (Tuple[str,str]) – Link end (as defined by body/reference point pair, see LinkEndId), for which the elevation angle viability setting is to be created. To apply these settings to all ground station on a given body (such as “Earth”), use [“Earth”, “”].

  • elevation_angle (float) – Limit elevation angle, below which no observations are produced when using the simulate_observations() function. Note: this value must be in radians.

Returns:

Instance of the ObservationViabilitySettings class, defining the settings for observation viability

Return type:

ObservationViabilitySettings

body_avoidance_viability(link_end_id: tuple[str, str], body_to_avoid: str, avoidance_angle: SupportsFloat) → tudatpy.kernel.estimation.observations_setup.viability.ObservationViabilitySettings

Function for defining body avoidance observation viability settings.

Function for defining body avoidance observation viability settings for single link ends. When simulating observations, this settings ensures that any applicable observations, for which the signal path passes ‘too close’ to a body, will be omitted. The definition of ‘too close’ is computed as the angle between:

  • The line-of-sight vector from a link end to a given third body

  • The line-of-sight between two link ends

This constraint is typically used to prevent the Sun from being too close to the field-of-view of the telescope(s), as defined by a so-called ‘SPE’ (Sun-Probe-Earth) angle constraint. The present viability setting generalizes this constraint.

Parameters:

  • link_end_id (Tuple[str,str]) – Link end (as defined by body/reference point pair, see LinkEndId ), for which the viability settings are to be created. To apply these settings to all ground station on a given body (such as “Earth”), use [“Earth”, “”] is entry in this list. For each link end included in this list, it will be checked if a signal received by and/or transmitted (or reflected) by this link end passes too close to the specified body.

  • body_to_avoid (str) – Name of the body which the signal path should not pass ‘too close’ to.

  • avoidance_angle (float) – Limit angle (generalization of SPE angle), below which no observations are produced when using the simulate_observations() function. Note: this value must be in radians.

Returns:

Instance of the ObservationViabilitySettings, defining the settings for observation viability.

Return type:

ObservationViabilitySettings

body_occultation_viability(link_end_id: tuple[str, str], occulting_body: str) → tudatpy.kernel.estimation.observations_setup.viability.ObservationViabilitySettings

Function for defining body occultation viability settings.

Function for defining body occultation viability settings for single link ends. When simulating observations, this setting ensures that any applicable observations, for which the signal path is occulted by a given body, will be omitted. The occultation is computed using the shape model of the specified body.

Parameters:

  • link_end_id (Tuple[str,str]) – Link end (as defined by body/reference point pair, see LinkEndId), for which the viability settings are to be created. To apply these settings to all ground station on a given body (such as “Earth”), use [“Earth”, “”] is entry in this list.

  • body_to_avoid (str) – Name of the body which the signal path should not be occulted by.

Returns:

Instance of the ObservationViabilitySettings, defining the settings for observation viability.

Return type:

ObservationViabilitySettings

elevation_angle_viability_list(link_end_ids: collections.abc.Sequence[tuple[str, str]], elevation_angle: SupportsFloat) → list[tudatpy.kernel.estimation.observations_setup.viability.ObservationViabilitySettings]

Function for defining list of elevation angle viability settings.

Function for defining elevation angle viability settings for multiple link ends. Each entry in the returned list contains the observation viability settings for one link end. When simulating observations, these settings ensure that any applicable observations, for which the local elevation angle at a link end is less than some limit value, will be omitted.

Parameters:

  • link_end_ids (List[ Tuple[str,str] ]) – List of individual link ends (as defined by body/reference point pair, see LinkEndId), for which the elevation angle viability setting is to be created. To apply these settings to all ground station on a given body (such as “Earth”), use [“Earth”, “”]. For each link end included in this list, it will be checked if a signal received by and/or transmitted (or reflected) by this link end violates the minimum elevation angle constraint.

  • elevation_angle (float) – Limit elevation angle, below which no observations are produced when using the simulate_observations() function. Note: this value must be in radians.

Returns:

List of ObservationViabilitySettings objects, each defining the settings for observation viability of one link end.

Return type:

ObservationViabilitySettings

body_avoidance_viability_list(link_end_ids: collections.abc.Sequence[tuple[str, str]], body_to_avoid: str, avoidance_angle: SupportsFloat) → list[tudatpy.kernel.estimation.observations_setup.viability.ObservationViabilitySettings]

Function for defining list of body avoidance viability settings.

Function for defining body avoidance viability settings for multiple link ends. Each entry in the returned list contains the observation viability settings for one link end. When simulating observations, these settings ensure that any applicable observations, for which the signal path passes ‘too close’ to a body, will be omitted. The definition of ‘too close’ is computed as the angle between:

  • The line-of-sight vector from a link end to a given third body

  • The line-of-sight between two link ends

This constraint is typically used to prevent the Sun from being too close to the field-of-view of the telescope(s), as defined by a so-called ‘SPE’ (Sun-Probe-Earth) angle constraint. The present viability setting generalizes this constraint.

Parameters:

  • link_end_ids (List[ Tuple[str,str] ]) – List of individual link ends (as defined by body/reference point pair, see LinkEndId), for which the elevation angle viability setting is to be created. To apply these settings to all ground station on a given body (such as “Earth”), use [“Earth”, “”].

  • body_to_avoid (str) – Name of the body which the signal path should not pass ‘too close’ to.

  • avoidance_angle (float) – Limit angle (generalization of SPE angle), below which no observations are produced when using the simulate_observations() function. Note: this value must be in radians.

Returns:

List of ObservationViabilitySettings objects, each defining the settings for observation viability of one link end.

Return type:

ObservationViabilitySettings

body_occultation_viability_list(link_end_ids: collections.abc.Sequence[tuple[str, str]], occulting_body: str) → list[tudatpy.kernel.estimation.observations_setup.viability.ObservationViabilitySettings]

Function for defining body occultation viability settings.

Function for defining body occultation viability settings for multiple link ends. Each entry in the returned list contains the observation viability settings for one link end. When simulating observations, these settings ensure that any applicable observations, for which the signal path is occulted by a given body, will be omitted. The occultation is computed using the shape model of the specified body.

Parameters:

  • link_end_ids (List[ Tuple[str,str] ]) – List of individual link ends (as defined by body/reference point pair, see LinkEndId), for which the viability settings are to be created. To apply these settings to all ground station on a given body (such as “Earth”), use [“Earth”, “”] is entry in this list. For each link end included in this list, it will be checked if a signal received by and/or transmitted (or reflected) by this link end is occulted by the specified body.

  • body_to_avoid (str) – Name of the body which the signal path should not be occulted by.

Returns:

List of ObservationViabilitySettings objects, each defining the settings for observation viability of one link end.

Return type:

ObservationViabilitySettings

add_viability_check_to_all(observation_simulation_settings_list: collections.abc.Sequence[tudatpy.kernel.estimation.observations_setup.observations_simulation_settings.ObservationSimulationSettings], viability_settings: collections.abc.Sequence[tudatpy.kernel.estimation.observations_setup.viability.ObservationViabilitySettings]) → None

Function for including viability checks into existing observation simulation settings.

Function for adding viability checks to the observation simulation settings, such that only observations meeting certain conditions are retained. The noise settings are added to all ObservationSimulationSettings object(s) in the observation_simulation_settings list. Note: the ObservationSimulationSettings objects are modified in-place by this function, and thus the function does not return anything.

Parameters:

  • observation_simulation_settings (List[ ObservationSimulationSettings ]) – Observation simulation settings, given by a list of one or more existing ObservationSimulationSettings objects.

  • viability_settings (List[ ObservationViabilitySettings ]) – List of one or more ObservationViabilitySettings objects, defining the viability checks to be included.

Returns:

The ObservationSimulationSettings object(s) are changed in-place.

Return type:

None

add_viability_check_to_observable(observation_simulation_settings_list: collections.abc.Sequence[tudatpy.kernel.estimation.observations_setup.observations_simulation_settings.ObservationSimulationSettings], viability_settings: collections.abc.Sequence[tudatpy.kernel.estimation.observations_setup.viability.ObservationViabilitySettings], observable_type: tudatpy.kernel.estimation.observable_models_setup.model_settings.ObservableType) → None

Function for including viability checks into existing observation simulation settings.

As add_viability_check_to_all(), except that the function only adds viabilitt settings to entries of the observation_simulation_settings list that matches the specified observable_type.

Parameters:

  • observation_simulation_settings (List[ ObservationSimulationSettings ]) – Observation simulation settings, given by a list of one or more existing ObservationSimulationSettings objects.

  • viability_settings (List[ ObservationViabilitySettings ]) – List of one or more ObservationViabilitySettings objects, defining the viability checks to be included.

  • observable_type (ObservableType) – Identifies the observable type in the observation simulation settings for which the viability checks are to be considered.

Returns:

The ObservationSimulationSettings object(s) are changed in-place.

Return type:

None

Function for including viability checks into existing observation simulation settings.

As add_viability_check_to_all(), except that the function only adds noise to entries of the observation_simulation_settings list that matches the specified observable_type and link_definition.

Parameters:

  • observation_simulation_settings (List[ ObservationSimulationSettings ]) – Observation simulation settings, given by a list of one or more existing ObservationSimulationSettings objects.

  • viability_settings (List[ ObservationViabilitySettings ]) – List of one or more ObservationViabilitySettings objects, defining the viability checks to be included.

  • observable_type (ObservableType) – Identifies the observable type in the observation simulation settings for which the viability checks are to be considered.

  • link_definition (LinkDefinition) – Identifies the link definition in the observation simulation settings for which the viability checks are to be considered.

Return type:

None

Enumerations

ObservationViabilityType

Enumeration of observation viability criterion types.
class ObservationViabilityType

Enumeration of observation viability criterion types.

Examples

# Code snippet to print all available Observation Viability Types
from tudatpy.estimation.observations_setup import viability

num_observation_viability_types = len(viability.ObservationViabilityType.__members__)
print(f'The length of all available Tudatpy Observation Viability Types is: {num_observation_viability_types}')

# Print all available Observation Viability Types using the "name" property
for i in range(num_observation_viability_types):
    print(i, viability.ObservationViabilityType(i).name)

Members:

minimum_elevation_angle

body_avoidance_angle

body_occultation

property name

Classes

ObservationViabilitySettings

Class for defining observation viability calculator settings.
class ObservationViabilitySettings

Class for defining observation viability calculator settings.

Class for defining the settings for observation viability calculator creation. Instances of this class are typically be created through various dedicated functions,such as elevation_angle_viability(), body_avoidance_viability() and body_occultation_viability()

Examples

# Code snippet to show the creation of an ObservationViabilitySettings object
import numpy as np
from tudatpy.estimation.observations_setup import viability

# Create ObservationViabilitySettings object
# In this case, we exclude observations for which the local elevation angle at link end is less 15 degrees.
min_elevation = np.deg2rad(15)
# We apply these settings to every ground station on Earth using the following link_end_id: [“Earth”, “”]
viability_settings = viability.elevation_angle_viability(["Earth", ""], min_elevation)

# Show that this is indeed an ObservationViabilitySettings object
print(viability_settings)