Q: How can I calculate a Gyro without a Gyro instrument, but at least two transponders?
A: At least two transponders (beacons) with offsets must be added to the respective vehicle.
To do that, click on "0" on the USBL instrument and then select the vehicle where the transponders will be added (this action must be done twice - for two transponders) (Fig. 1)
Fig. 1 - Adding transponders to the subsea vehicle
Once added, the two transponders will be shown under the subsea vehicle (Fig. 2)
Fig. 2 - Transponders added to the subsea vehicle
Check the offsets are added and they are correct (Fig. 3)
Fig. 3 - Checking the offsets
When going online, make sure the transponders are added into Remote/UW positioning systems (Fig. 4)
Fig. 4 - Adding the transponders and going online
At this point, a gyro value can be calculated with the help of the two (or more) transponders, with different offsets. Please note, the calculation is less accurate than a normal gyro reading and cannot be recorded, only viewed in Helmsman, Data View (Fig. 5)
Fig. 5 - DataView in Helmsman