HelicopterLandingZones Task

This task performs raster identification of helicopter landing zones.

For additional details on helicopter landing zones, see Helicopter Landing Zones.

Example

; Start the application

e = ENVI()

; Open an input point cloud file

File = Filepath(DataSample.las', $

  SUBDIRECTORY=['data','lidar'], $

  ROOT_DIR=e.ROOT_DIR)

pointCloud = e.OpenPointCloud(File, $

  PROJECT_URI=e.GetTemporaryFilename(''))

; Use the point cloud feature extraction task to generate

; a digital surface model (DSM) from the point cloud

dsmTask = ENVITask('PointCloudFeatureExtraction')

dsmTask.INPUT_POINT_CLOUD = pointCloud

dsmTask.DSM_GENERATE = 1

dsmTask.Execute

; Open the resulting DSM raster and close the point cloud object

dsmRaster = e.OpenRaster(dsmTask.OUTPUT_PRODUCTS_INFO.DSM_URI)

pointCloud.Close

; Get the helicopter landing zones task from the catalog of ENVITasks

hlzTask = ENVITask('HelicopterLandingZones')

; Define the input raster

hlzTask.INPUT_RASTER = dsmRaster

; Run the task

hlzTask.Execute

; Get the collection of data objects currently available in the Data Manager

DataColl = e.Data

; Add the output to the Data Manager

DataColl.Add, hlzTask.OUTPUT_RASTER

; Display the result

View = e.GetView()

Layer = View.CreateLayer(hlzTask.OUTPUT_RASTER)

Syntax

Result = ENVITask('HelicopterLandingZones')

Input parameters (Set, Get): HELO_SIZE, HELO_TYPE, HOVER_HEIGHT, INPUT_RASTER, LANDING_GEAR, OPERATING_CONDITIONS, OUTPUT_RASTER_URI, USE_HOVER, ZONE_SIZE

Output parameters (Get only): OUTPUT_RASTER

Parameters marked as "Set" are those that you can set to specific values. You can also retrieve their current values any time. Parameters marked as "Get" are those whose values you can retrieve but not set.

Input Parameters

HELO_SIZE (optional)

Specify the size of the helicopter in meters. This parameter is only used if HELO_TYPE is set to User-Defined. The default value is 15.

HELO_TYPE (optional)

Specify the type of helicopter. The following values are allowed:

User-Defined: Permits custom user input. If selected, use the HELO_SIZE and ZONE_SIZE parameters to set the landing zone parameters.
Light Observation: Includes helicopters such as the OH-6 Little Bird and the OH-58 Kiowa.
Light Utility: Includes helicopters such as the UH-1 Iroquois "Huey", the AH-1 Cobra, and the H-65 Dolphin.
Medium Utility: Includes helicopters such as the AH-64 Apache, the UH-60 Blackhawk, and the H-2 Seasprite.
Cargo: Includes helicopters such as the CH-47 Chinook, the CH-53 Sea Stallion, and the H-3 Sea King.
Slingload: For helicopter operations using a slingload.
Slingload Long-line: For helicopter operations using a long-line slingload.
Slingload with NVGs: For helicopter operations using a slingload with night vision goggles (NVGs).

The default value is Medium Utility.

HOVER_HEIGHT (optional)

Specify the hovering height in meters. This parameter is only used if USE_HOVER is set to 1. The default value is 3.

INPUT_RASTER (required)

Specify a digital surface model raster with which to identify helicopter landing zones.

LANDING_GEAR (optional)

Specify the type of landing gear used by the helicopter, Skidsor Wheels. The default value is Wheels.

OPERATING_CONDITIONS (optional)

Specify the operating conditions for the helicopter landing zone. Allowed values are Day, Day (permissive), and Night. The default value is Day.

OUTPUT_RASTER_URI (optional)

Specify a string with the fully qualified filename and path of the associated OUTPUT_RASTER.

If you do not specify this parameter, or set it to an exclamation symbol (!), ENVI creates a temporary file.
If you set it to the hash symbol (#), ENVI creates a file in the temporary directory, but this file will not be deleted when ENVI closes.