I think I just had a brilliant idea.
I was listening to the woes of dealing with the dead weight of a sex doll... 🤔 and get this: modular hollow skeletons.
I might post design sketches if there's any interest (Revi? Phil? Love nestle?). But basically, the joints could be universal (hips, knees, shoulders, etc), and the segments between could vary in shape and length. This could significantly reduce weight, rubber material, and decrease development costs for new models.
The extremities (hands and feet) would be too delicate for such a construction method, but having extra weight at the extremities (compared to the limbs) might very well result in a doll that acts more lively (think of the chaotic motion of a double pendulum).
Cheap limbs could be constructed of plastic (or Styrofoam) while high end could be aluminum or a spring steel cage, assembled in strips. Spring steel cage could eliminate the possibility of permanent denting.
@Mr_Mister - Ah, my bad.... 😅
I meant for the internal skeleton. No joints would be visible or accessible from the outside. The hollow limbs would be internal, encased in a single continuous envelope of silicone/TPE.
In order to attempt such a limb transfer, a person would have to cut into the skin.
I should work up a quick draft sketch, and post it. I gotta start my work shift, but maybe tomorrow.