Page:Advanced Automation for Space Missions.djvu/286

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mining robot will be at least 1-2 orders of magnitude more complicated than Agin's system, so we would estimate a control requirement of 106-107 bytes, or about 107-108 bits of computer capacity.

The SRI expert system "PROSPECTOR" runs on a DEC-10 computer with a 150K operating program and a 1M database, a total of about 3.2X107 bits (Hart, personal communication , 1980). PROSPECTOR "knows" about 1000 different factors related to prospecting. It is difficult to imagine a general excavation expert system requiring more than ten times this, or 10,000 factors, to achieve adequate autonomous operation with troubleshooting capability - the PROSPECTOR expert has generated some impressively accurate results in searches for ore-bearing bodies. If the "EXCAVATOR" expert system is thus about one order of magnitude larger than PROSPECTOR, the basic computational requirement is 10M or 3.2X108 bits.

Mining robot executive computer requirements are more difficult to estimate, as there are few previous directly applicable models. A simple passenger aircraft autopilot probably will run on a 32K microprocessor, and a "smart rover" vision-equipped wheeled mobile robot with a 6-degree-of-freedom arm developed in the 1970s at JPL used state-of-the-art microprocessors. Remarks by Sacerdoti (1979, 1980) on the subject of autonomous planning and execution in robotics suggest that the system required for robot miners is perhaps 1 to 2 orders of magnitude beyond current technology; thus the executive system may require a memory capacity of about 1 to 10M, or 3 to 30X107 bits.

Summing the requirements for the three major computer subsystems gives an "information bandwidth budget" of 3.6-7.2X108 bits, centering on about 500 Mb. The information necessary to completely describe the system for purposes of self-replication is probably on the order of 109 bits.


5D.4 LMF Approach and Access Geometry


In the baseline LMF scenario, mining robots must assume all hauling duties beyond the factory platform. Thus, it becomes necessary to specify how these mobile machines, normally bearing loads of strip-mined soil to be processed, will approach the factory and deposit their cargoes at an appropriate input location. A related query is how and where robots will accept waste products for transport to the pit for use as landfill. These questions are of some importance, because as the seed expands to full maturity it may become physically more difficult to exchange raw materials and wastes with interior LMF processing systems unless the access geometry has been designed to accommodate growth.


figure 5.39. - LMF constant-angle wedge corridor access route.