Hi @troydej, welcome to the forum! 
Looks like an interesting design. Have you considered much with respect to the net vehicle buoyancy, and the desired movement speed(s)? It seems like you don’t have any buoyancy foam at the moment, in which case
- that’s either not shown/hasn’t been considered, or
- you’re planning for the enclosures to provide sufficient buoyancy themselves, or
- the vehicle will only be operating in very dense liquid (e.g. the dead sea), or
- the vertical thrusters will need to make up for the difference (i.e. the vehicle is intended to sink, and requires actuation/pulling the tether to get back to the surface)
Noice
You might need some ribbing in there, and/or quite thick material for the walls. Our 6" Acrylic Enclosure Tubes look to be a bit shorter than yours, and we only rate them to 65m depth. You might want to take a look at Under Pressure when determining the enclosure specifics, if you haven’t already