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IAgAccessConstraint Interface

Description

AgAccessConstraint used to access the AccessConstraint attributes

Public Properties

Public Property ConstraintNameProperty used to access the constraint name.
Public Property ConstraintTypeProperty used to access the constraint type.
Public Property ExclIntvlExclude Time Intervals
Public Property IsPluginThis property is deprecated. It is now read-only.
Public Property MaxRelMotionMaximum relative motion used in adaptive sampling.
Public Property MaxTimeStepMaximum time step used in adaptive sampling.

CoClasses that Implement IAgAccessConstraint

Example

Return a list of available constraints
[Python]
# IAgAccessConstraintCollection accessConstraints: Access Constraint collection
constraintArray = accessConstraints.AvailableConstraints()

print('List of Available Constraints:')
for i in range(0,len(constraintArray)):
   print(constraintArray[i])
Add and configure a lighting condition access constraint
[Python]
# IAgAccessConstraintCollection accessConstraints: Access Constraint collection

# Condition constraint
light = accessConstraints.AddConstraint(25) # eCstrLighting
light.Condition = 0 # eDirectSun
Add and configure a LOS sun exclusion access constraint
[Python]
# IAgAccessConstraintCollection accessConstraints: Access Constraint collection

# Angle constraint
cnstrAngle = accessConstraints.AddConstraint(29) # eCstrLOSSunExclusion
cnstrAngle.Angle = 176.0
Add and configure a lunar elevation angle access constraint
[Python]
# IAgAccessConstraintCollection accessConstraints: Access Constraint collection

minmax = accessConstraints.AddConstraint(30) # eCstrLunarElevationAngle
minmax.EnableMin = True
minmax.Min = 11.1
minmax.EnableMax = True
minmax.Max = 88.8
Add and configure a sun elevation angle access constraint
[Python]
# IAgAccessConstraintCollection accessConstraints: Access Constraint collection

minmax = accessConstraints.AddConstraint(58) # eCstrSunElevationAngle
minmax.EnableMin = True
minmax.Min = 22.2
minmax.EnableMax = True
minmax.Max = 77.7
Add and configure a third body obstruction access constraint
[Python]
# IAgAccessConstraintCollection accessconstraints: Access Constraint collection
# Get IAgAccessCnstrThirdBody interface
thirdBodyConstraint = accessConstraints.AddConstraint(61) # eCstrThirdBodyObstruction

# AvailableObstructions returns a one dimensional array of obstruction paths
availableArray = thirdBodyConstraint.AvailableObstructions

# In this example add all available obstructions
print('Available obstructions')
for i in range(0,len(availableArray)):
   print(availableArray[i])
   thirdBodyConstraint.AddObstruction(availableArray[i])

# AssignedObstructions returns a one dimensional array of obstruction paths
assignedArray = thirdBodyConstraint.AssignedObstructions

print('Assigned obstructions')
for i in range(0,len(assignedArray)):
    print(assignedArray[i])
Add and configure an altitude access constraint
[Python]
# IAgAccessConstraintCollection accessConstraints: Access Constraint collection

# Attitude constraint
altitude = accessConstraints.AddConstraint(2) # eCstrAltitude
altitude.EnableMin = True
altitude.Min = 20.5 # km
Add multiple access constraints of the same type to an STK Object
[Python]
# IAgAccessConstraintCollection accessConstraints: Access Constraint collection

# Add constraints
# Only the eCstrApparentTime (4), eCstrDuration (13), eCstrGMT (16), eCstrIntervals (22), eCstrLocalTime (27) constraint
# types can be added multiple times to the constraint collection.
time1 = accessConstraints.AddConstraint(27) # eCstrLocalTime
time1.Min = '00:00:00.000'
time1.Max = '23:00:00.000'
Add an Exclusion Zone access constraint
[Python]
# IAgAccessConstraintCollection accessConstraints: Access Constraint collection
excludeZone = accessConstraints.AddNamedConstraint('ExclusionZone')
excludeZone.MaxLat = 45
excludeZone.MinLat = 15
excludeZone.MinLon = -75
excludeZone.MaxLon = -35
Remove all access constraints except for LOS
[Python]
# IAgAccessConstraintCollection accessConstraints: Access Constraint collection
for i in range(accessConstraints.Count-1,0,-1):
    constraint = accessConstraints.Item(i).ConstraintName

    if (constraint == 'LineOfSight') == False:
        if (constraint == 'ThirdBodyObstruction'):
            thirdBodyConstraint = accessConstraints.GetActiveNamedConstraint('ThirdBodyObstruction')
            assignedArray = thirdBodyConstraint.AssignedObstructions

            for j in range (0,len(assignedArray)):
                thirdBodyConstraint.RemoveObstruction(assignedArray[j])
            end

        elif (constraint == 'ExclusionZone'):
            accessConstraints.GetActiveNamedConstraint('ExclusionZone').RemoveAll()

        else:
            accessConstraints.RemoveNamedConstraint(constraint)
Configure the access interval to the availability time span of the object where access is being computed to.
[Python]
# IAgStkObjectRoot root: STK Object Model root

satellite = root.GetObjectFromPath('/Satellite/MySatellite')
facility = root.GetObjectFromPath('/Facility/MyFacility')
access = satellite.GetAccessToObject(facility)

access.AccessTimePeriod = 2 # eUserSpecAccessTime
accessTimePeriod = access.AccessTimePeriodData

if (satellite.Vgt.EventIntervals.Contains('AvailabilityTimeSpan')):
    availabilityTimeSpan = satellite.Vgt.EventIntervals.Item('AvailabilityTimeSpan')
    accessTimePeriod.AccessInterval.SetImplicitInterval(availabilityTimeSpan)
GetAccessBetweenObjectsByPath using the output of GetExistingAccesses
[Python]
# IAgStkObjectRoot root: STK Object Model root
scenario = root.CurrentScenario
accesses = scenario.GetExistingAccesses()

size = len(accesses)  # number of accesses

object1 = accesses[0][0]   # e.g. "Satellite/MySatellite"
object2 = accesses[0][1]  # e.g.  "Facility/MyFacility"
computed = accesses[0][2]        # e.g. True  (if access has been computed)

access = scenario.GetAccessBetweenObjectsByPath(object1, object2)
Return a list of available constraints
[MATLAB]
% IAgAccessConstraintCollection accessConstraints: Access Constraint collection
constraintArray = accessConstraints.AvailableConstraints;

disp('List of Available Constraints:');
for i=1:length(constraintArray)
   disp(constraintArray{i,1});
end
Add and configure a lighting condition access constraint
[MATLAB]
% IAgAccessConstraintCollection accessConstraints: Access Constraint collection

% Condition constraint
light = accessConstraints.AddConstraint('eCstrLighting');
light.Condition = 'eDirectSun';
Add and configure a LOS sun exclusion access constraint
[MATLAB]
% IAgAccessConstraintCollection accessConstraints: Access Constraint collection

% Angle constraint
cnstrAngle = accessConstraints.AddConstraint('eCstrLOSSunExclusion');
cnstrAngle.Angle = 176.0;
Add and configure a lunar elevation angle access constraint
[MATLAB]
% IAgAccessConstraintCollection accessConstraints: Access Constraint collection

minmax = accessConstraints.AddConstraint('eCstrLunarElevationAngle');
minmax.EnableMin = true;
minmax.Min = 11.1;
minmax.EnableMax = true;
minmax.Max = 88.8;
Add and configure a sun elevation angle access constraint
[MATLAB]
% IAgAccessConstraintCollection accessConstraints: Access Constraint collection

minmax = accessConstraints.AddConstraint('eCstrSunElevationAngle');
minmax.EnableMin = true;
minmax.Min = 22.2;
minmax.EnableMax = true;
minmax.Max = 77.7;
Add and configure a third body obstruction access constraint
[MATLAB]
% IAgAccessConstraintCollection accessconstraints: Access Constraint collection
% Get IAgAccessCnstrThirdBody interface
thirdBodyConstraint = accessConstraints.AddConstraint('eCstrThirdBodyObstruction');

% AvailableObstructions returns a one dimensional array of obstruction paths
availableArray = thirdBodyConstraint.AvailableObstructions;

% In this example add all available obstructions
disp('Available obstructions');
for i=1:length(availableArray)
   disp(availableArray{i,1});
   thirdBodyConstraint.AddObstruction(availableArray{i,1});
end

% AssignedObstructions returns a one dimensional array of obstruction paths
assignedArray = thirdBodyConstraint.AssignedObstructions;

disp('Assigned obstructions');
for i=1:length(assignedArray)
    disp(assignedArray{i,1});
end
Add and configure an altitude access constraint
[MATLAB]
% IAgAccessConstraintCollection accessConstraints: Access Constraint collection

% Attitude constraint
altitude = accessConstraints.AddConstraint('eCstrAltitude');
altitude.EnableMin = true;
altitude.Min = 20.5;    % km
Add multiple access constraints of the same type to an STK Object
[MATLAB]
% IAgAccessConstraintCollection accessConstraints: Access Constraint collection

% Add constraints
% Only the eCstrApparentTime, eCstrDuration, eCstrGMT, eCstrIntervals, eCstrLocalTime constraint
% types can be added multiple times to the constraint collection.
time1 = accessConstraints.AddConstraint('eCstrLocalTime');
time1.Min = '00:00:00.000';
time1.Max = '23:00:00.000';
Add a Exclusion Zone access constraint
[MATLAB]
% IAgAccessConstraintCollection accessConstraints: Access Constraint collection
excludeZone = accessConstraints.AddNamedConstraint('ExclusionZone');
excludeZone.MaxLat = 45;
excludeZone.MinLat = 15;
excludeZone.MinLon = -75;
excludeZone.MaxLon = -35;
Remove all access constraints except for Line Of Sight
[MATLAB]
% IAgAccessConstraintCollection accessConstraints: Access Constraint collection
for i=accessConstraints.Count - 1:-1:0
    constraint = accessConstraints.Item(i).ConstraintName;

    if (strcmp(constraint,'LineOfSight')) == false
        if (strcmp(constraint,'ThirdBodyObstruction'))
            thirdBodyConstraint = accessConstraints.GetActiveNamedConstraint('ThirdBodyObstruction');
            assignedArray = thirdBodyConstraint.AssignedObstructions;

            for j=1:length(assignedArray)
                thirdBodyConstraint.RemoveObstruction(assignedArray{j});
            end

        elseif (strcmp(constraint,'ExclusionZone'))
            accessConstraints.GetActiveNamedConstraint('ExclusionZone').RemoveAll;

        else
            accessConstraints.RemoveNamedConstraint(constraint);
        end
    end
end
Remove Line of Sight access constraint
[MATLAB]
% IAgAccessConstraintCollection accessConstraints: Access Constraint collection
accessConstraints.RemoveNamedConstraint('LineOfSight');
Configure the access interval to the availability time span of the object where access is being computed to.
[MATLAB]
% IAgStkObjectRoot root: STK Object Model root

satellite = root.GetObjectFromPath('/Satellite/MySatellite');
facility = root.GetObjectFromPath('/Facility/MyFacility');
access = satellite.GetAccessToObject(facility);

access.AccessTimePeriod = 'eUserSpecAccessTime';
accessTimePeriod = access.AccessTimePeriodData;

if (satellite.Vgt.EventIntervals.Contains('AvailabilityTimeSpan'))
    availabilityTimeSpan = satellite.Vgt.EventIntervals.Item('AvailabilityTimeSpan');
    accessTimePeriod.AccessInterval.SetImplicitInterval(availabilityTimeSpan);
end
GetAccessBetweenObjectsByPath using the output of GetExistingAccesses
[MATLAB]
% IAgStkObjectRoot root: STK Object Model root
scenario = root.CurrentScenario;
accesses = scenario.GetExistingAccesses();

[row, col] = size(accesses);  % number of accesses

object1 = accesses{1,1};   % e.g. "Satellite/MySatellite"
object2 = accesses{1,2};  % e.g.  "Facility/MyFacility"
computed = accesses{1,3};          % e.g. true  (if access has been computed)

access = scenario.GetAccessBetweenObjectsByPath(object1, object2);
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