James Casler

Work design and analysis for space-based manufacturing: a case analysis of initial design issues

The purpose of the present research was to investigate the nature of potential manufacturing tasks humans may execute in a space environment. The success of space-based manufacturing (SBM) is suggested to be a precursor to permanent human presence in space. A working hypothesis for this study was that human work in the SBM environment would be substantially different from terrestrial manufacturing work. To investigate this hypothesis, a case analysis approach was developed that employed a function allocation and task analysis of a representative SBM process: the production of tailored industrial crystals. This research approach was chosen as the current state of engineering design for SBM is in the conceptual and early flow sheeting phases of a system life cycle. Results of the task analysis and function allocation process suggest response to corrective maintenance functions and to abnormal system conditions should be allocated to humans as opposed to automation. These results are discussed in relation to human factors engineering challenges associated with long-duration human presence in an SBM environment.

Rectenna Array Equipped on Satellites

Space solar-power satellites may one day transmit large amounts of high-powered microwave beams to Earth from geostationary Earth orbit. New spacecraft can be designed to prosper from this new available source of energy by equipping future spacecraft with a rectenna array or hybrid photovoltaic/rectenna array system. This idea offers prospective benefits, such as extending the mission lifetime of the spacecraft through increasing the life of the power generation function and reducing the power generation units mass. This paper explores the integration of rectenna array and hybrid photovoltaic/rectenna array systems into future spacecraft and compares this method to the conventional photovoltaic array method, considering mission and component life, mass, area, and energy harvesting capabilities. Cost is compared between conventional photovoltaic array and the rectenna array. This paper shows that the integrated hybrid photovoltaic/rectenna array power generation unit seems a viable option in obtaining the ...