Still working on a new prototype of the actuator. After a lot of thinking, I am now trying out a magnetic solution like sthone mentioned earlier. I already had the magnets and this approach should be more reliable and have less wear problems.
I also decided to go away from the oil filled electric compartments. At least for now. So what I have done is bought two water filter housings. I got the idea from "MR Fishing ROV" on youtube. After doing some research I found out that the "20inch big blue" type of housing will fit all my batteries and electronics. I could not find any source for these here in Norway so I had to order from the UK. I received it a couple of days ago and it's really solid! thick plastic, good seal and two 1" ports that will be used for thruhulls. These are rated for 9bar operating pressure, witch I believe is quite a bit on the safe side. While digging I found that the rated failure pressure (burst pressure) is around 30bar. Off course this is all pressure from the inside! situation will be different with pressure from the outside. This is the reason I asked about pre pressurizing the hull over at the "Frames, Hulls, & Bouyancy" part of the forum. I will ad a valve to allow for this. putting 5bar of pressure in the hull before diving should easily allow me to reach 100m ( 5bar of outside pressure actin on the hull) at least in theory
The smaller, clear filter housing will house my two ip cameras, one is wide angled and the other has a slight zoom on it to allow a more close up video feed of the manipulator. I will also have room for a gopro, lasers for measuring and a servo to tilt it all up and down.
This housing was much cheaper, but not as well built. A little reinforcing of the oring seal from the inside is needed.
The clear part is quite optically clear and I could see almost no distortion. The plastic it's made of scratches easily, but a replacement part is only $10 from the local hardware store.
This means that the old frame design is out the window and a new one needs to be made.
What are your thoughts?