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Access Enumerations

Enumeration types used in access computation.

LookDirection

LookDirection 

LookDirection()

Look direction of a satellite relative to its velocity vector.

Indicates whether a satellite is looking to the left (counterclockwise from velocity), right (clockwise from velocity), or either direction.

This is commonly used for imaging satellites with side-looking sensors or SAR systems that have a preferred look direction.

Attributes:

Name Type Description
LEFT Any

Left-looking (counterclockwise from velocity vector)
RIGHT Any

Right-looking (clockwise from velocity vector)
EITHER Any

Either left or right is acceptable
Example 
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import brahe as bh

# Create a constraint for right-looking only satellites
constraint = bh.LookDirectionConstraint(allowed=bh.LookDirection.RIGHT)

# Create a constraint accepting either direction
constraint = bh.LookDirectionConstraint(allowed=bh.LookDirection.EITHER)

# Compare look directions
assert bh.LookDirection.LEFT != bh.LookDirection.RIGHT
assert bh.LookDirection.LEFT == bh.LookDirection.LEFT

Initialize instance.

EITHER class-attribute 

EITHER: Any = LookDirection.Either

Look direction of a satellite relative to its velocity vector.

Indicates whether a satellite is looking to the left (counterclockwise from velocity), right (clockwise from velocity), or either direction.

This is commonly used for imaging satellites with side-looking sensors or SAR systems that have a preferred look direction.

Attributes:

Name Type Description
LEFT

Left-looking (counterclockwise from velocity vector)
RIGHT

Right-looking (clockwise from velocity vector)
EITHER

Either left or right is acceptable
Example 
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import brahe as bh

# Create a constraint for right-looking only satellites
constraint = bh.LookDirectionConstraint(allowed=bh.LookDirection.RIGHT)

# Create a constraint accepting either direction
constraint = bh.LookDirectionConstraint(allowed=bh.LookDirection.EITHER)

# Compare look directions
assert bh.LookDirection.LEFT != bh.LookDirection.RIGHT
assert bh.LookDirection.LEFT == bh.LookDirection.LEFT

LEFT class-attribute 

LEFT: Any = LookDirection.Left

Look direction of a satellite relative to its velocity vector.

Indicates whether a satellite is looking to the left (counterclockwise from velocity), right (clockwise from velocity), or either direction.

This is commonly used for imaging satellites with side-looking sensors or SAR systems that have a preferred look direction.

Attributes:

Name Type Description
LEFT

Left-looking (counterclockwise from velocity vector)
RIGHT

Right-looking (clockwise from velocity vector)
EITHER

Either left or right is acceptable
Example 
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import brahe as bh

# Create a constraint for right-looking only satellites
constraint = bh.LookDirectionConstraint(allowed=bh.LookDirection.RIGHT)

# Create a constraint accepting either direction
constraint = bh.LookDirectionConstraint(allowed=bh.LookDirection.EITHER)

# Compare look directions
assert bh.LookDirection.LEFT != bh.LookDirection.RIGHT
assert bh.LookDirection.LEFT == bh.LookDirection.LEFT

RIGHT class-attribute 

RIGHT: Any = LookDirection.Right

Look direction of a satellite relative to its velocity vector.

Indicates whether a satellite is looking to the left (counterclockwise from velocity), right (clockwise from velocity), or either direction.

This is commonly used for imaging satellites with side-looking sensors or SAR systems that have a preferred look direction.

Attributes:

Name Type Description
LEFT

Left-looking (counterclockwise from velocity vector)
RIGHT

Right-looking (clockwise from velocity vector)
EITHER

Either left or right is acceptable
Example 
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import brahe as bh

# Create a constraint for right-looking only satellites
constraint = bh.LookDirectionConstraint(allowed=bh.LookDirection.RIGHT)

# Create a constraint accepting either direction
constraint = bh.LookDirectionConstraint(allowed=bh.LookDirection.EITHER)

# Compare look directions
assert bh.LookDirection.LEFT != bh.LookDirection.RIGHT
assert bh.LookDirection.LEFT == bh.LookDirection.LEFT

AscDsc

AscDsc 

AscDsc()

Ascending or descending pass type for satellite orbits.

Indicates whether a satellite is moving from south to north (ascending) or north to south (descending) in its orbit. This is determined by the sign of the Z-component of the velocity vector in ECEF coordinates.

This is useful for: - Sun-synchronous orbits that prefer specific pass types - Minimizing lighting variation between passes - Coordinating multi-satellite observations

Attributes:

Name Type Description
ASCENDING Any

Satellite moving from south to north (vz > 0 in ECEF)
DESCENDING Any

Satellite moving from north to south (vz < 0 in ECEF)
EITHER Any

Either ascending or descending is acceptable
Example 
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import brahe as bh

# Create a constraint for ascending passes only
constraint = bh.AscDscConstraint(allowed=bh.AscDsc.ASCENDING)

# Create a constraint for descending passes only
constraint = bh.AscDscConstraint(allowed=bh.AscDsc.DESCENDING)

# Accept either type
constraint = bh.AscDscConstraint(allowed=bh.AscDsc.EITHER)

# Compare pass types
assert bh.AscDsc.ASCENDING != bh.AscDsc.DESCENDING
assert bh.AscDsc.ASCENDING == bh.AscDsc.ASCENDING

Initialize instance.

ASCENDING class-attribute 

ASCENDING: Any = AscDsc.Ascending

Ascending or descending pass type for satellite orbits.

Indicates whether a satellite is moving from south to north (ascending) or north to south (descending) in its orbit. This is determined by the sign of the Z-component of the velocity vector in ECEF coordinates.

This is useful for: - Sun-synchronous orbits that prefer specific pass types - Minimizing lighting variation between passes - Coordinating multi-satellite observations

Attributes:

Name Type Description
ASCENDING

Satellite moving from south to north (vz > 0 in ECEF)
DESCENDING

Satellite moving from north to south (vz < 0 in ECEF)
EITHER

Either ascending or descending is acceptable
Example 
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import brahe as bh

# Create a constraint for ascending passes only
constraint = bh.AscDscConstraint(allowed=bh.AscDsc.ASCENDING)

# Create a constraint for descending passes only
constraint = bh.AscDscConstraint(allowed=bh.AscDsc.DESCENDING)

# Accept either type
constraint = bh.AscDscConstraint(allowed=bh.AscDsc.EITHER)

# Compare pass types
assert bh.AscDsc.ASCENDING != bh.AscDsc.DESCENDING
assert bh.AscDsc.ASCENDING == bh.AscDsc.ASCENDING

DESCENDING class-attribute 

DESCENDING: Any = AscDsc.Descending

Ascending or descending pass type for satellite orbits.

Indicates whether a satellite is moving from south to north (ascending) or north to south (descending) in its orbit. This is determined by the sign of the Z-component of the velocity vector in ECEF coordinates.

This is useful for: - Sun-synchronous orbits that prefer specific pass types - Minimizing lighting variation between passes - Coordinating multi-satellite observations

Attributes:

Name Type Description
ASCENDING

Satellite moving from south to north (vz > 0 in ECEF)
DESCENDING

Satellite moving from north to south (vz < 0 in ECEF)
EITHER

Either ascending or descending is acceptable
Example 
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import brahe as bh

# Create a constraint for ascending passes only
constraint = bh.AscDscConstraint(allowed=bh.AscDsc.ASCENDING)

# Create a constraint for descending passes only
constraint = bh.AscDscConstraint(allowed=bh.AscDsc.DESCENDING)

# Accept either type
constraint = bh.AscDscConstraint(allowed=bh.AscDsc.EITHER)

# Compare pass types
assert bh.AscDsc.ASCENDING != bh.AscDsc.DESCENDING
assert bh.AscDsc.ASCENDING == bh.AscDsc.ASCENDING

EITHER class-attribute 

EITHER: Any = AscDsc.Either

Ascending or descending pass type for satellite orbits.

Indicates whether a satellite is moving from south to north (ascending) or north to south (descending) in its orbit. This is determined by the sign of the Z-component of the velocity vector in ECEF coordinates.

This is useful for: - Sun-synchronous orbits that prefer specific pass types - Minimizing lighting variation between passes - Coordinating multi-satellite observations

Attributes:

Name Type Description
ASCENDING

Satellite moving from south to north (vz > 0 in ECEF)
DESCENDING

Satellite moving from north to south (vz < 0 in ECEF)
EITHER

Either ascending or descending is acceptable
Example 
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import brahe as bh

# Create a constraint for ascending passes only
constraint = bh.AscDscConstraint(allowed=bh.AscDsc.ASCENDING)

# Create a constraint for descending passes only
constraint = bh.AscDscConstraint(allowed=bh.AscDsc.DESCENDING)

# Accept either type
constraint = bh.AscDscConstraint(allowed=bh.AscDsc.EITHER)

# Compare pass types
assert bh.AscDsc.ASCENDING != bh.AscDsc.DESCENDING
assert bh.AscDsc.ASCENDING == bh.AscDsc.ASCENDING