Not exactly world-changing. But it will help region....

 

What would also help, is a giant 3D pen. Held by a fixated limb

(rods connected together by movable joints)

that can carry the weight for the user, and move in all axis.

I mentioned this long time ago I believe.

 

That can print out not only plastic,

but wooden filaments, and metal filaments to an extent.

 

Advantages: No computer required, nor training.

Immediate use.

 

Purpose, more sophisticated parts. Even that wooden scooter

apparently has some springs in there. Meaning, printed out a

spring (in plastic), using greensands, metal parts can be casted.