Aggregate Obstacles (Aviation)

Available with Aviation Charting license.

Summary

Aggregates obstacle features within a given radius so that the highest obstacle in the group represents the entire group.

The tool provides a better cartographic representation of obstacle data on dense or crowded charts. Instead of being displayed individually, obstacle data can be represented as groups of obstacles based on the location of the highest obstacle in each group.

Usage

• The tool uses the geometry and attribution of the obstacle at the highest Above Mean Sea Level (AMSL) elevation (measured at either the base or the top of the obstacle) to represent all obstacles within a search radius of that obstacle.

• Obstacles are considered for grouping if they are as tall or taller (height above ground level) than the provided height threshold (or the built-up area height threshold if inside a built-up area polygon).

• You can specify whether obstacle elevations are measured on the ground at the base of the obstacle or at the top of the obstacle.

Parameters

Dialog

Label	Explanation	Data Type
Obstacle Features	The input obstacle features.	Feature Layer
Height Field	The field containing the height of the obstacle features.	String
Height Field Units	Specifies the units that will be used for obstacle height. Meters—The obstacle height will be in meters. Decimeters—The obstacle height will be in decimeters. Centimeters—The obstacle height will be in centimeters. Millimeters—The obstacle height will be in millimeters. Yards—The obstacle height will be in yards. Feet—The obstacle height will be in feet. This is the default. Inches—The obstacle height will be in inches.	String
Elevation Field	The field containing the elevation of the obstacle features.	String
Elevation Field Units	Specifies the units that will be used for obstacle elevation. Meters—The obstacle elevation will be in meters. Decimeters—The obstacle elevation will be in decimeters. Centimeters—The obstacle elevation will be in centimeters. Millimeters—The obstacle elevation will be in millimeters. Yards—The obstacle elevation will be in yards. Feet—The obstacle elevation will be in feet. This is the default. Inches—The obstacle elevation will be in inches.	String
Elevation Interpretation	Specifies how obstacle elevations will be measured. On the Ground—Elevation values will be measured using the AMSL elevation of the base of the obstacle. The height value will be added to the elevation value to determine the elevation of the top of the obstacle. Above the Ground—Elevation values will be measured using the AMSL elevation of the top of the obstacle. This is the default.	String
Target Obstacle Group Features	The output feature class to which aggregated obstacle features will be written.	Feature Layer
Target Obstacle Group Label	The text describing the obstacle grouping. The text is used to identify obstacle groups for different chart specifications that may be created using different parameters.	String
Obstacle Association Table	A table that will be populated with information linking each obstacle group feature to the obstacles it represents.	Table View
Search Radius (Optional)	The radius within which the obstacles will be grouped.	Linear Unit
Height Threshold (Optional)	The height threshold for an obstacle to be considered for grouping. Obstacles with a height value greater than or equal to this value will be considered.	Linear Unit
Built-Up Areas (Optional)	Polygon features designating built up areas. These represent areas where a different height threshold is required.	Feature Layer
Built-Up Areas Height Threshold (Optional)	The height threshold for an obstacle within a built-up area polygon to be considered for grouping. Obstacles with a height value equal to or greater than this value will be considered.	Linear Unit

Derived Output

Label	Explanation	Data Type
Updated Obstacle Group Features	The updated obstacle group features.	Feature Layer

Python

arcpy.aviation.AggregateObstacles(in_obstacle_features, height_field, height_field_units, elevation_field, elevation_field_units, elevation_interpretation, target_obstacle_group_features, target_obstacle_group_label, in_obstacle_assocation_table, {search_radius}, {height_threshold}, {builtup_areas_features}, {builtup_areas_height_threshold})

Name	Explanation	Data Type
in_obstacle_features	The input obstacle features.	Feature Layer
height_field	The field containing the height of the obstacle features.	String
height_field_units	Specifies the units that will be used for obstacle height. METERS—The obstacle height will be in meters. DECIMETERS—The obstacle height will be in decimeters. CENTIMETERS—The obstacle height will be in centimeters. MILLIMETERS—The obstacle height will be in millimeters. YARDS—The obstacle height will be in yards. FEET—The obstacle height will be in feet. This is the default. INCHES—The obstacle height will be in inches.	String
elevation_field	The field containing the elevation of the obstacle features.	String
elevation_field_units	Specifies the units that will be used for obstacle elevation. METERS—The obstacle elevation will be in meters. DECIMETERS—The obstacle elevation will be in decimeters. CENTIMETERS—The obstacle elevation will be in centimeters. MILLIMETERS—The obstacle elevation will be in millimeters. YARDS—The obstacle elevation will be in yards. FEET—The obstacle elevation will be in feet. This is the default. INCHES—The obstacle elevation will be in inches.	String
elevation_interpretation	Specifies how obstacle elevations will be measured. ON_THE_GROUND—Elevation values will be measured using the AMSL elevation of the base of the obstacle. The height value will be added to the elevation value to determine the elevation of the top of the obstacle. ABOVE_THE_GROUND—Elevation values will be measured using the AMSL elevation of the top of the obstacle. This is the default.	String
target_obstacle_group_features	The output feature class to which aggregated obstacle features will be written.	Feature Layer
target_obstacle_group_label	The text describing the obstacle grouping. The text is used to identify obstacle groups for different chart specifications that may be created using different parameters.	String
in_obstacle_assocation_table	A table that will be populated with information linking each obstacle group feature to the obstacles it represents.	Table View
search_radius (Optional)	The radius within which the obstacles will be grouped.	Linear Unit
height_threshold (Optional)	The height threshold for an obstacle to be considered for grouping. Obstacles with a height value greater than or equal to this value will be considered.	Linear Unit
builtup_areas_features (Optional)	Polygon features designating built up areas. These represent areas where a different height threshold is required.	Feature Layer
builtup_areas_height_threshold (Optional)	The height threshold for an obstacle within a built-up area polygon to be considered for grouping. Obstacles with a height value equal to or greater than this value will be considered.	Linear Unit

Derived Output

Name	Explanation	Data Type
updated_obstacle_group_features	The updated obstacle group features.	Feature Layer

Code sample

AggregateObstacles example (stand-alone script)

The following script demonstrates how to use the AggregateObstacles function.

# Import system modules
import arcpy

# Check out extensions
arcpy.CheckOutExtension("Aeronautical")

# Set environment settings
arcpy.env.workspace = r"C:/data/AIS.gdb"

# Set local variables
in_obstacle_features = "Obstacle"
height_field = "HEIGHT_VAL"
height_field_units = "FEET"
elevation_field = "ELEV_VAL"
elevation_field_units = "FEET"
elevation_interpretation = "ABOVE_THE_GROUND"
target_obstacle_group_features = "ObstacleGroup"
target_obstacle_group_label = "Enroute Series"
in_obstacle_assocation_table = "ObstacleAssociation"
search_radius = "1.5 NauticalMiles"
height_threshold = "100 Feet"
builtup_areas_features = "BuiltUpAreas"
builtup_areas_height_threshold = "300 Feet"

# Call the AggregateObstacles tool
arcpy.aviation.AggregateObstacles(in_obstacle_features,\
                                  height_field, height_field_units, elevation_field,\
                                  elevation_field_units, elevation_interpretation,target_obstacle_group_features,\
                                  target_obstacle_group_label,\
                                  in_obstacle_assocation_table, search_radius,\
                                  height_threshold, builtup_areas_features,\
                                  builtup_areas_height_threshold)

# Check in extensions
arcpy.CheckInExtension('Aeronautical')

Environments

This tool does not use any geoprocessing environments.

Licensing information

• Basic: No
• Standard: Requires ArcGIS Aviation Charting
• Advanced: Requires ArcGIS Aviation Charting