Session
Technical Session III: Systems/Buses
Abstract
The SPINSAT Bus is a three axis stabilized, light weight, inexpensive spacecraft capable of orbit changing (elliptic to circular, co-planar, plus inclination adjustment), orbit maintenance (altitude adjustment to assure ground trace repeatability) and, in final operational orbit, accurate earth pointing (± 0.5 degrees). The Bus also provides thermal control, telecommunication, data storage and electrical power for modest sized payloads to perform a variety of low-earth orbit (LEO) missions of up to three years duration. The baseline Bus version is a cylindrical shape (914.4 mm [36 inch] diameter by 902.2 mm [35.52 inch] height). The outer surface is covered with solar cells and for this mission, four extendable panels covered with solar cells supply 115 watts orbit average under the worst case (high noon) orbit. The baseline design is compatible with Scout or Pegasus launch vehicles. For the first SPINSAT mission, the maximum launch weight (on Scout) is 166.5 kg (367.1 Ibs) including an altimeter payload of 43.1 kg (1.95 Ibs). This paper will define the mission analysis that drove the design, the mission sequence of events and give a brief description of the Bus systems. The present launch target date is March 29, 1990 from Vandenberg, launch complex SLC 5.
The SPINSAT Bus: New and Old in a Small Package
The SPINSAT Bus is a three axis stabilized, light weight, inexpensive spacecraft capable of orbit changing (elliptic to circular, co-planar, plus inclination adjustment), orbit maintenance (altitude adjustment to assure ground trace repeatability) and, in final operational orbit, accurate earth pointing (± 0.5 degrees). The Bus also provides thermal control, telecommunication, data storage and electrical power for modest sized payloads to perform a variety of low-earth orbit (LEO) missions of up to three years duration. The baseline Bus version is a cylindrical shape (914.4 mm [36 inch] diameter by 902.2 mm [35.52 inch] height). The outer surface is covered with solar cells and for this mission, four extendable panels covered with solar cells supply 115 watts orbit average under the worst case (high noon) orbit. The baseline design is compatible with Scout or Pegasus launch vehicles. For the first SPINSAT mission, the maximum launch weight (on Scout) is 166.5 kg (367.1 Ibs) including an altimeter payload of 43.1 kg (1.95 Ibs). This paper will define the mission analysis that drove the design, the mission sequence of events and give a brief description of the Bus systems. The present launch target date is March 29, 1990 from Vandenberg, launch complex SLC 5.
