Engineering topics
Publications and source records attributed to Erickson, J. A..
Parameterized Investigation of Launch Opportunities and Trajectories (PILOT) program developed to perform mission simulation computations that yield data for use in delimiting optimum launch windows. CoPILOT utility program used to read and format PILOT-generated data file.
General Maneuver Program, GMAN, computes both orbital and spin-axis reorientation maneuver parameters for various spacecraft. Specifically, GMAN computes detailed maneuver scenarios necessary to achieve desired orbit and attitude maneuvers. Program supports both spinning and inertially-fixed despun spacecraft and includes modeling for either hydrazine or Freon propulsion system.
Control of the trajectory and attitude for the International Sun-Earth Explorer-3 (ISEE-3) spacecraft is performed using an onboard hydrazine propulsion system. This paper describes the spacecraft hardware and operational limitations that were considered in the planning, execution, and evaluation of all ISEE-3 maneuvers performed to date. Propulsion system performance and spacecraft dynamics models as implemented in the maneuver support computer software are described. Examples are presented that show how maneuver goals are achieved while satisfying mission orbit and attitude constraints. Procedures used in the development of maneuver plans are detailed for the second midcourse correction maneuver which typifies maneuver operations in general.