... An inflatable space station might be dangerous in case of a debris hitting it?
Cheers,
Oriol
A friend (parachute rigger) worked as a technician on Bigelow Aerospace's inflatable module that was added to the International Space Station. They used multiple-layer walls made of puncture resistant fabric to limit the damage done by small bits of space trash. Large bits of space trash will puncture any metal space craft.
On the subject of inflatable kayaks, there have been at least 5 generations.
The first generation of foldable kayaks (Klepper, Folbot, et.) were built the same way as the original Eskimo (Inuit in Canada) with sticks covered in fabric. Clever joints allowed the user to quickly assemble the wooden frame and stretch the fabric around the outside. I used to have a Folboat and spent many leisurely hours using it to explore local rivers and lakes.
Later versions of Folboat added inflatable tubes along the sides to tighten the hull and provide some emergency floatation.
The third generation only used inflatable tubes (ala. inflatable emergency life raft). These were great for white-water rafting, but lacked the long-sleek hulls needed for speed and efficiency on long trips.
The fourth generation (Advanced Elements) has inflatable tubes enclosed in a second layer of heavy-duty fabric. It also has aluminum stiffeners in the bow and stern to increase the finesse ratio (length to width). It works well, but is overly complex and slow to dry.
The latest generation uses through-stitched side walls and bottom. This is similar to the Air-Mat that Goodyear used to build their Inflate-O-Planes circa 1960. These have far fewer parts because they do not need an extra, outer layer of fabric for streamlining. They can be built as perfectly flat sheets or gently curved sheets (similar to plywood). The 2 layers of fabric are held at a constant distance by thousands of through-stitches. Try to picture rib stitching on a fabric-covered biplane. Outer layers carry most of the tensile and twisting loads, while through-stitches hold them in precise alignment and compressed air (5 psi above atmosphere) carries all the compressive loads ... sort of a tensegrity structure with compressed air replacing all the little sticks. These inflated boats stay rigid as long as internal pressure exceeds external pressure. These double-layer sheets are similar to the through-stitching currently fashionable on inflatable stand-up paddle-boards.
Current through-stitch sewing machines can only make constant-thickness sheets, but I predict that the next few years will see more sophisticated machines that will be able to sew contoured hulls of varying thickness. I anticipate that sophisticated through-stitch machines will soon allow square parachute (and para-glider) factories to eliminate all the finicky ribs currently sewn into their inflatable wings.
