Ok I didn't mention something. It's actually not a submarine, but an underwater camera (shaped like a submarine) and its actually being towed by a boat. Therefore it will go at a decent speed. It's 3'' large, and 10'' long, and we want to use this product https://www.bluerobotics.com/store/rov/bluerov2/newton-gripper-asm-r1-rp/ and turn it into a simple linear actuator, and transform its linear movement into rotary movement to move the planes angles, so the camera can change its depth while being towed.
So I see you guys are pretty much in favor of going for a rotary actuator instead, but we already have this gripper and its really strong, reliable and reusable, and mostly easy to use because we can only use the servo library without any additional hardware.
The only I need is to see what would be an easy way to turn that linear energy into rotary. Thanks!