opening an existing scene with
Open Scene
and adding to it. If you don’t, you will be prompted
to create a scene file when you begin scanning.
If you select New Scene, SceneVision-3D will ask you to choose a folder for the new scene
folder – the default is C:\deltasphere\data. Once selected, it will display all the existing scene
folders in that folder. Type in a name for the new scene and SceneVision will create a new
folder for the scene as well as a new scene file. All new data for the scene will be automatically
organized in this new folder.
4.3
Scan Parameters
With the connection to the DeltaSphere established and a scene file created you are ready to set
the parameters for your first scan. Scan parameters include the horizontal and vertical fields-of-
view, the density of scanned points, the scanning speed and a maximum scan range, as well as a
destination file for the data. These will be explained individually in the sections that follow.
The DeltaSphere-3000 scans a vertical array of points, then rotates about the vertical axis for the
next vertical array, repeating this process until the specified field of view has been covered.
The coordinate system used is much like the latitude/longitude system on the surface of the
earth, or azimuth/elevation coordinates used in surveying.
4.3.1
Setting Scan Parameters
Horizontal Field of View
The Horizontal Field of View is set by specifying the start (minimum) and end (maximum)
horizontal rotation of the scan. 0º is defined to be the perpendicular view coming out from the
front of the DeltaSphere (the side with the DeltaSphere-3000 label, see Figure 1).
Negative horizontal values are defined to be a clockwise rotation when looking at the
DeltaSphere from above; positive horizontal values are counterclockwise. The DeltaSphere
always scans in a counterclockwise or positive direction.
To specify the horizontal FOV, type the Min and Max values in the Horizontal FOV boxes
found at the bottom left part of the SceneVision window.
For example, using the values -90º to 90º would execute a 180º scan beginning from a position
90º clockwise from the initial position and ending 90º counterclockwise. The scanner rotates
clockwise (‘backs up’) 90º before beginning to scan. A 360º scan can be executed by specifying
–180º to 180º, 0 to 360º, or some other variation. The scans would begin at different points but
would each provide a 360º scan. (The –180º to 180º scan requires less slack cable and is
preferred.) Horizontal FOV values are limited to the range –360º to 360º (which would execute
a 720º scan).
DeltaSphere-3000 3D Scene Digitizer
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