Continuously emerging additive manufacturing technologies, especially developments within the last decade, offer new opportunities for producing metallic parts. The project 2ARMY addresses the growing needs regarding the on-demand production of spare parts and repairing worn metallic components. The maintenance units can use mobile deployable workshops for additive manufacturing and significantly improve the availability of critically important weapon systems and equipment on the battlefield. The possibility of producing the old and eventually unavailable parts in sufficient quality and maintaining existing worn parts is expected to have a positive economic impact on the lifetime of related systems and their short-time availability. It can be especially relevant for military use. Three vital system components of such a mobile and partially autonomous robotic cell for wire and arc additive manufacturing and repair of metallic parts were investigated during the project. Optical 3D acquisition of the part's actual shape and computation of the difference to the expected part's geometry is desirable for process automation. An appropriate 3D-scanning system has been found and integrated with available robotic welding cell. Algorithms were developed for automatically detecting the damaged regions on the part and for path generation according to the suitable manufacturing strategy. Furthermore, the current challenges regarding the quality assurance of additively manufactured parts were addressed. A digital signal acquisition chain was developed to monitor dynamic GMAW process variants. The designed database allows more in-depth analysis of the manufacturing process and optimisation of the non-destructive testing methods. A damaged part has been repaired, and a spare part has been produced to illustrate the capability of the methods, algorithms and system components developed during the project 2ARMY.