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A system trade study was conducted to determine the feasibility of a 2007 Mars sample return (MSR) mission utilizing the Martian atmosphere for in-situ propellant production (ISPP). A hybrid zirconia and SabatierElectrolysis (S E) process ISPP system was assumed that produced liquid oxygen and liquid methane. The emphasis of the study was threefold. First, to determine what impact the choice in mixture ratio of the oxygedmethane propellant combination used for Mars ascent has on the overall injected mass from Earth of the MSR mission elements. Second, to ascertain if the 2003/2005 "workhorse" lander being designed for MSR missions can be modified to accommodate a 2007 ISPP MSR mission. Third, to identify what parameters and technologies have a significant impact on the overall injected mass of the MSR mission elements. This paper also summarizes the current status of ISPP work funded by the NASA through the Jet Propulsion Laboratory (JPL). It was determined that the choice in mixture ratio has a moderate impact on the overall injected mass from Earth of the MSR mission elements. Although it satisfies the injected mass constraint of an affordable medium"? launch vehicle, a 2007 ISPP MSR mission cannot be accomplished using a modified 2003/2005 "workhorse" lander due to configuration and packaging issues. Configuration, propulsion, power, and thermal control appear to be the four areas with the highest impact on the overall feasibility and injected mass for an ISPP MSR mission. Technology investment in these areas is required to make a 2007 ISPP MSR feasible.

NASA exploration missions to Mars, initiated by the Mars Pathfinder mission in July 1997, will continue over the next decade. The missions require challenging innovations in robot design and improvements in autonomy to meet ambitious objectives under tight budget and time constraints. The authors are developing design tools, component technologies and capabilities to address these needs for manipulation with robots for planetary exploration. The specific developments are: 1) a software analysis tool to reduce robot design iteration cycles and optimize on design solutions, 2) new piezoelectric ultrasonic motors (USM) for light-weight and high torque actuation in planetary environments, 3) use of advanced materials and structures for strong and light-weight robot arms and 4) intelligent camera-image coordinated autonomous control of robot arms for instrument placement and sample acquisition from a rover vehicle.

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