Table 1.

Classification of size levels for assembly objects in on-orbit assembly.

Assembly Object Level	Description	Corresponding Project
Spacecraft Assembly	Assembly of large functional structures is completed in orbit by mating two or more spacecraft.	MIR, ATV
Multiple Modules Assembly	Spacecraft on-orbit assembly is autonomously completed by multiple modules/segments	ETS-VII, Hubble Telescope
Module Assembly	Large structures are autonomously assembled in orbit by modules	Dragonfly
Module Expansion	Enhancement of spacecraft functionality is achieved through module replacement technology.	Phoenix
Part Manufacturing and Assembly	Parts are manufactured through material processing and autonomously assembled in orbit	SpiderFab, Arichnaut