A Space Station/Payload Pointing System Simulation using TREETOPS

A rigid body model of NASA´s Space Station (SS)/Payload Pointing System (PPS) was built and simulated using the multi-body, large angle simulation package TREETOPS [1]. The name TREETOPS refers to the class of structures which may be simulated by the program, ie., those having a tree topology. SS/PPS data from a previous feasibility study (conducted by NASA Goddard Space Flight Space Center [2]) utilizing the Multi Optimal Differential Equation Language (MODEL) [3] was used as a test case to evaluate the built-in dynamical formulation capabilities of TREETOPS. The simulation results showed close agreement with GSFC demonstrating the validity of the nonlinear, large angle, multi-degree of freedom TREETOPS models.