Engineering improvements: Automated astronomic positioning system

The Automated Astronomic Positioning System (AAPS) is a portable astrogeodetic field instrument developed to provide astronomic latitude and longitude. It is impersonal and automatic and performs most of the computations at the site using a miniature CONTROL DATA 469 Computer. These features substantially reduce the training and office computations currently required of conventional astrogeodetic methods. This is a final report covering the provisioning of spare parts and a reengineering study aimed at the recommendation of software and hardware improvements. A number of minor changes were found to significantly increase equipment usability. The incorporation of an FK4 star catalog reduces latitude offset by a factor of two. The dominant cause of random error appears to lie within the level sensor bubble and manifests itself in three forms: non-flatness of the reference surface (less than 0.5 arc second), sensitivity (not substantiated in the field). Several hardware and software modifications are recommended for incorporation, and it is further recommended that a level measurement scheme be evaluated.