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“ SMF establishment and growth requires a vigorous parallel development of the three basic materials/energy functions - raw materials and materials processing, manufacturing and technology, and energy production. As the SMF increases in output and creates new net resources, unit output costs should fall and an ever-increasing array of commercially interesting products and services will come into existence. ”

“ The manufacture of complex products containing sophisticated electronic specialized materials may require the preparation of pure glasses and synthetic crystals. Production steps that need to be developed include material separation and sophisticated materials processing.
Consider, for example, the manufacture of synthetic quartz semiconductor materials. Plagioclase first is separated from lunar soil by electrophoresis or other techniques. The refined mineral is then fused and its chemical composition altered to induce quartz to crystallize from the cooling solution. ”

“ The two main components of the magnetic-pulse former are the forming coil and the capacitor. Robots with appropriate wrist actions should be capable of conventional winding operations to manufacture forming coils from extruded wire. The capacitor may consist of a basalt/aluminum or alumina/aluminum sandwich based on the standard formula C = kEA/d, where C is capacitance, k is the dielectric constant of basalt or alumina (4.5-8.4 at 106 Hz) , E is the permittivity of free space, A is capacitor plate area, and d is plate spacing.
A third example is electroforming technology. ”

“ Substitution and comprehensive manufacture of electronics components are beyond the scope of the present study. Even with this limited review, it is encouraging to note the number of instances in which space equals or is superior to terrestrial factory environments for the manufacture of electronic components. ”

“ Two of the most important advanced products to be manufactured in space are robots and teleoperator mechanisms. The ultimate goals for SMF cannot be attained without a significant expansion of the automation equipment initially deployed from Earth. Space robots and teleoperators eventually must be designed from working experience following initial deployment of the starting kit, and then manufactured in space. ”

“ Automated assembly of advanced devices is perhaps no more difficult than the automated assembly of satellites, which already will have been accomplished during an earlier phase of SMF evolution. The most crucial technologies to be developed for the manufacture of second- and third-generation robots and teleoperators are space-adaptive sensors and computer vision. ”

“ Further growth and increased complexity are required if the SMF is to evolve from the starting kit into a sophisticated manufacturing center which depends less and less on Earth for raw materials resupply. One key growth area especially significant in view of the heavy requirements for computers and robotics in space is the automated fabrication of integrated circuitry and other electronics components. ”

“ In-space production of satellite; will require the manufacture of special components for control, observation, and communication, and a significant evolutionary advance in automation technology. Satellites may represent the first highly complicated, coordinated construction challenge to be undertaken entirely by teleoperators or robots in space. The construction of solar-power panels, antennas, and sophisticated computer control and communications modules demands a versatile new manipulator system. ”

“ Overall shape is controlled by surface tension, external forces, and directed solar heating. Vapor deposition is another potentially favorable technique which should be given high research priority. Also, as the human presence in space expands, special production environments that allow the use of gases and liquids will become more commonplace. ”

“ Successful fractionation of quartz from an altered plagioclase melt requires significant advances in the techniques of controlled nucleation, crystallization, and zone refining. Development of a special materials-production capability will permit the manufacture of space-made solar panels, solid-state lasing crystals, fiber optics, and perhaps solar sails. ”

“ Valued as payload at about $1000/kg, an empty tank is worth about $33.5 million, less additional propulsion costs but plus added value derived from conversion of tank mass to useful products by the SMF. If Shuttle flies every 2 weeks, the payload value of the tank masses inserted into orbit would be the equivalent of roughly $1 billion per year. To an orbital space manufacturing economy this represents new additional income, in this case the equivalent of about 20% of the current annual NASA budget. ”

“ Conventional photolithography and diffusion techniques are not feasible for space electronics fabrication. Many of the required chemical elements are present in lunar soil only at the ppm or ppb level. Photoresists consist largely of hydrocarbons, substances whose atoms are rare and which deteriorate rapidly in the space environment. ”

“ A number of complex products representing various evolutionary steps not yet mentioned or discussed might include impulse landers, biological products, storage tanks, mobile rovers, nuclear power stations, agricultural products, and many others integral to the evolution of a complex products manufacturing capability. ”

“ Glasses and fibers - can be manufactured by using casting, grinding, and die-extrusion operations. Grinding is required for optical-quality glass shapes. Electron-beam and laser techniques are useful for final finishing of optical surfaces. Adhesives and coatings - of metals and ceramics can be applied by the starting kits or a specialized kit suited to the particular geometries of certain parts. ”

“ Condensibles may prove a bigger cleanliness problem than particles. Techniques for coping with them include avoiding line-of-sight exposure to sources, use of materials with high vapor pressures, and installation of cold traps. ”

“ Basic elements of discrete fixed capacitors include metal plates or foil, dielectric material, and wire leads. The plates or foil and leads can be contrived from readily available aluminum. Alumina, silica, and a variety of glass and ceramic materials provide suitable dielectrics. All of these substances are readily available from lunar sources.
Two capacitor fabrication techniques - thin- and thick-film - are compatible with silicon integrated circuit technology, though discrete capacitors generally are preferred over thick-film versions (Glaser and Subak-Sharpe, 1977) . ”

“ Metals, ceramics, and ceramic/metal combinations can also be prepared. Refractories and dies - can be manufactured using the powder metallurgical components of the starting kit. Laser trimming can be performed as required after solidification and inspection of the part. These components then become available for casting complex shapes and for extruding both long-dimension components and parts designed to sustain very high temperatures and pressures. Heating - by direct solar energy may initially be accomplished using aluminum deposited on spherical surfaces. ”

“ One final critical issue is cleanliness. Particulates should pose fewer problems in space than on Earth because of the absence of atmosphere for convective transfer. An aperture in the fabrication facility enclosure opposite the SMF velocity vector, suitably baffled, should provide a clean vacuum source. ”

“ Fabrication capability in these five critical areas will permit most other necessary components to be produced as well. For instance, an IC fabrication facility could manufacture at least some varieties of transistors, diodes (rectifiers, small-signal, and zener) , varactors, thyristors, silicon-controlled rectifiers (SCRs) , and others. ”