Conceptual design of a 1979 Mars rover
The results of a conceptual design study of a Mars roving vehicle mission in 1979 are presented. Descriptions of the mission, science objectives, vehicle configuration and subsystems are included. Mission analysis parameters required to define a mission profile and sequence of events are presented. Science operations including the deployment of small, self-contained, long-lived meteorology and/or seismology stations are considered. The vehicle system is described by the functional requirements, vehicle configuration and weight and power allocations. Following the system description, seven subsystems on board the vehicle are considered. The characteristics and capabilities of each are described. Mission operations also were evaluated to the degree necessary to identify the areas of foremost concern. INTRODUCTION In future decades, the space science community will be provided with unique and challenging opportunities to explore the solar system by spacecraft of increased complexity, longer lifetime and more autonomy. A candidate mission is an automated traverse on Mars. Roving vehicles capable of extended operation on the surface, and sufficiently mobile to traverse regions remote from acceptable landing sites, would offer scientists the opportunity to explore large regions of the planetary surface. The value of landed spacecraft in performing scientific explorations and surveying future landing sites for manned vehicles was demonstrated by the Surveyor lunar missions. Surveyor, a "fixedpoint" surface spacecraft, collected composition and topographic data within local areas about the landing sites. In many cases, however, areas of scientific interest are likely to be in regions remote from acceptable spacecraft landing sites, since acceptable landing sites are chosen from topographic as well as scientific criteria. Furthermore, many scientifically interesting areas are likely to exist on the Martian surface and exploration of all of these areas by immobile surface spacecraft is clearly impractical. Given the premise that long Martian surface distances are to be explored, the automated surface roving vehicle appears to be a prime means for achieving these exploration goals. To focus and bound this conceptual design study, several assumptions were defined. These limited the depth of effort in certain areas and eliminated some of the tradeoffs that otherwise could have been performed. Throughout the study these assumptions were adhered to, and interpretation of the results should include the effect of these study assumptions. The key assumptions made were: (a) Six-wheeled vehicle concept The six-wheeled vehicle concept has been shown by several previous studies(l» 2, 3) to provide the "best" mobility capability and the "best" overall design for operation on unknown surfaces. (b) Direct-link communications with earth A relay communications link with an orbiting vehicle was not considered, although relay communications may be practical and desirable in some instances. (c) One routine science operation performed per day Some science data should be collected during each day of the mission. This includes possibly imaging, meteorology, etc. , but does not always include operation of the lifedetection experiments. (d) No locomotion during the Martian night Since no communications with the earth can be effected with a direct link during the Martian night, the risk to the safety of the vehicle becomes quite high. This paper presents the results of one phase of research carried out at the Jet Propulsion Laboratory, ;Galifornia Institute of Technology, under Contract No. NAS 7-100, sponsored by the National Aeronautics ,and Space Administration.
A conceptual design and operational characteristics for a Mars rover for a 1979 or 1981 Viking science mission
The feasibility of a small Mars rover for use on a 1979 or 1981 Viking mission was studied and a preliminary design concept was developed. Three variations of the concept were developed to provide comparisons in mobility and science capability of the rover. Final masses of the three rover designs were approximately 35 kg, 40 kg, and 69 kg. The smallest rover is umbilically connected to the lander for power and communications purposes whereas the larger two rovers have secondary battery power and a 2-way very high frequency communication link to the lander. The capability for carrying Viking rovers (including development system) to the surface of Mars was considered first. It was found to be feasible to carry rovers of over 100 kg. Virtually all rover systems were then studied briefly to determine a feasible system concept and a practical interface with the comparable system of a 1979 or 1981 lander vehicle.
The unfolded universe of elementary particles. A geometric explanation of the standard model structure
We propose a geometric explanation of the standard model of Glashow, Weinberg and Salam for the known elementary particles. Our model is a generic Quantum Field Theory in dimension four, obtained by developing along a Lorentz sub-manifold the lagrangian of Einstein and Dirac in dimension twelve. The main mechanism which gives birth to the standard model is a certain gauge fixing of triality, which permits to identify the multiplicity of fermions, as seen from the four dimensional world, with the eight unseen dimensions of the generating universe. In this way we get the known tables of particles, explaining the series of fermions and the gauge bosons. We suggest that the Higgs field dynamics could appear through a bosonization of the right handed neutrino and correspond to a displacement in the unseen dimensions. We also propose hypotheses for dark matter, and perhaps dark energy. Then we suggest predictions to go beyond the standard model.