Knowledgebase
Imagenex Delta T
Posted by Jerry Knisley, Last modified by
Notice
Undefined index: editedstaff (C:/inetpub/wwwroot/Support/__swift/cache/8ffb74eb8fb5aeb3f7fb2e375265078e.php:44)
Copy to clipboard:
on 09 December 2014 02:02 PM

HYSWEEP driver for the Delta T multibeam.  Provides multibeam soundings via a network interface.

 

Setup Form:

There are two methods of time tagging Delta T data; (1) PC arrival time or (2) UTC time.  The arrival time method works fine but for more accurate time tags select the UTC method.  If UTC time is used, auxiliary sensors (GPS, MRU, gyro) must be time synched to UTC also.

 

Connection:

All data is via a network interface.  Set network card internet address 192.168.0.4, subnet mask 255.255.255.0.  Set HYSWEEP connection as shown:

 

 

 

Sonar Offsets:

  • Starboard:  Sonar head locations starboard of boat reference.
  • Forward: Sonar head locations forward of boat reference.
  • Vertical: Sonar head locations relative to waterline (positive).
  • Yaw, Pitch, Roll:  Sonar head rotations - enter values determined by patch testing.
  • Latency:  Enter 0.

 

Notes:

  • Two computers are required; One runs the Delta T multibeam, the other runs HYPACK / HYSWEEP.  Communication is over the Ethernet cable. 
  • Both computers must be time synchronized to UTC time if Delta T UTC time tagging is selected.
  • The MRU should be connected to both computers.  The Delta T does real-time roll corrections and provides roll corrected data.  HYSWEEP needs the pitch and heave corrections.
  • It is very easy to change the number of Delta T beams.  Don’t do it.  Select the number you like (120 or 240, 480 seems excessive in shallow water) and stick with it throughout the survey.  Changing sector size also changes number of beams.  If you do change the number of beams, you will need to fix number of beams to 480 in MBMAX post-processing (Advanced Read Parameters).


Attachments 
 
 imagenexdeltat1.jpg (13.16 KB)
 imagenex delta t2.jpg (30.19 KB)
 imagenex delta t 3.jpg (9.67 KB)