Accession Number : ADA222006


Title :   Local Design Methodologies for a Hierarchic Control Architecture


Descriptive Note : Final rept. 9 Jan 1988-30 Jun 1989


Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE SPACE SYSTEMS LAB


Personal Author(s) : How, Jonathan P ; Hall, Steven R ; Crawley, Edward F


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a222006.pdf


Report Date : 12 Apr 1990


Pagination or Media Count : 217


Abstract : The problems associated with the control of large intelligent space structures with many sensors and actuators has previously led to the development of a hierarchic control architecture. This control arrangement consists of a two level combination of a centralized global controller and a set of local controllers which are distributed to complement the dynamic behavior of the structure. Four decentralized control methodologies which are suitable for implementation at the lower level of the hierarchic architecture are developed and analyzed in this thesis. The first design only allows colocated feedback. The second design allows feedback from within a region of the structure. The third allows communication between adjacent local controllers so that information from neighboring regions can be used for the feedback. The last employs a distributed implementation of the full state feedback. The simulation results for the control of a long beam in bending show that employing the more complicated decentralized designs at the lower level of the hierarchic architecture will slightly improve the overall performance. However, the implementation costs for these more sophisticated designs are shown to increase dramatically. The most efficient hierarchic design for this beam example is one which combines a good flobal design with a simple colocated feedback. This conclusion may change for structures which require more performance at the local level. Keywords: Active control; Distributed; Hierarchic control; Local control designs.


Descriptors :   *COMPUTER ARCHITECTURE , *SPACECRAFT , *CONTROL SYSTEMS , ACTUATORS , DETECTORS , DYNAMIC RESPONSE , CENTRALIZED , SIMULATION , REGIONS , FEEDBACK , COMPUTER APPLICATIONS , METHODOLOGY , THESES


Subject Categories : Mechanics
      Unmanned Spacecraft


Distribution Statement : APPROVED FOR PUBLIC RELEASE