Trident Compass


Hi there, im an absolute beginner with the Trident and i like it very much.
However i found that the compass 0° direction is pointing East, like we do in mathematics. Is there a way to set it to a navigational standard, with 0° pointing to the North?


The Trident IMU software assigns a zero degree heading to the orientation of the ROV each time that it is powered up. To capture true or magnetic north for a particular dive, use a compass to align the ROV body and then attach tether to power up the unit.

Best, Howard


Thanks Howard!
I was just going to add that the behaviour seem to be a bit irrational, but now you made it make sense to me.


Glad it helped a bit Anders,
… Good Luck.


I don’t believe the orientation of Trident matters when you power it on. Please check out the compass calibration response by Eric in this thread. There is some other useful info about using your control device compass as well. One interesting thing I have noticed is that my device compass (Nvidea Sheild K1) is usually not that accurate so I have had to ignore it most of the time. The trident compass has been accurate most of the time.


Apr 13

Hey all! If the device you’re using has a built in compass (tablets as well as the Trident controller don’t but phones often do) then an additional arrow will show up that indicates the direction that device is pointing for reference. For devices without an internal compass, the reference arrow won’t appear. The larger vehicle arrow for

Trident is linked to a magnetometer on-board the vehicle that detects magnetic north and also fuses that data with a rate gyro. In order for this system to work well, the vehicle usually needs to be calibrated. To do this, I recommend (before starting your dive) rotating the vehicle back and forth about each of its three axis several times. This will allow the magnetometer to detect where north is and ignore other magnificent fields.

We’re still catching up on documentation, but we hope to have a tutorial for all this stuff sometime soon. Thank you everyone for helping each-other get this stuff figured out in the meantime!