We picture the tubular home, although it could also be a pod, having a “prow” on one or both ends, much like this:
This could be attached to each other in a flexible, energy producing (a pump at minimum!) set up, the Sea Train:
Or be attached to some a backbone extending from a bigger structure like a lens or ramform.
This backbone could also act as communications and piping.
It could be non flexible:
Or have different degrees of flexibility: