We had some extra time so our engineers yesterday developed 360 mount for bluerov2. 
Made .stl and…
After 23h hours
they decided that 3D printer had some layer problems around 60%. Eventough nobody really cares… and it fits perfectly…
and it fits perfectly…
they are not happy… they send me message few minutes ago… guess what …now they are developing generative design… and already made CFD calculations… 
This is really cool! Maybe Google Earth will hire you to do the streetview underwater :). Where did you get the transparent sphere?
cool!
how is its stability in the water？
I find that a transparent sphere at the bottom of the BlueROV2.
What are the merits and demerits between them?
What are the stability differences between, having the bubble/sphere the top vs bottom?
Generally you want underwater vehicles to be statically stable. This can be most simply achieved by keeping the center of buoyancy above the center of mass. The exact degree of stability is more dependent on relative moments of mass and buoyancy, for lack of the more technical term.
In short Bubble on top of the ROV relatively good stability, perhaps an improvement in stability, maybe not, if it shifts the relative moment too much. Bubble on bottom of ROV is going to negatively impact static stability.
If anybody is interested we are selling bubble and mount.
next week we will make it transparent…
