Underwater robots

Some underwater robots. These robots use acrylic for their structures. The robot components are encased in acrylic boxes that have lids secured by stainless steel screws and waterproofed by O-rings. Electrical connections between the waterproof boxes are made via acrylic nipples and silicone tubing. Each component is designed to have its density the same as water and its centre of gravity to coincide with its centre of pressure.