Modeling, tuning, and effectiveness of partiallyfilled ring nutation dampers
Abstract
Computer simulation is used to study the effect of various parameters on nutation dampers to be used in the dynamically complex Combined Release and Radiation Effects Satellite (CRRES). The concepts governing the design construction of the two dampers used in the CRRES are also presented. Each damper is modeled as a planar pendulum whose motion is opposed by a damping torque acting as a pivot. The damping torque is nonlinear because the liquid in the real damper flows laminarly part of the time and turbulently another part of the time. Equations for optimal offset, a function of spacecraft inertia ratio, are given together with curves relating damping effectiveness to viscosity and offset. Results indicate that the damping obtainable from a partially filled offset ring nutation (PFORN) damper is a strong function of: (1) satellite mass properties and spin rate; (2) damper offset, height and radius; (3) damper fluid density and viscosity; and (4) damper fill angle. It is concluded that PFORN dampers can effectively dampen nutation in spinning rigid bodies when they incorporate the applicable inertia ratio. They also contribute periods of less than 200 sec on a satellite such as the CRRES when its wire booms are extended.
 Publication:

Guidance and Control 1985
 Pub Date:
 1985
 Bibcode:
 1985guco.conf..431K
 Keywords:

 Computerized Simulation;
 Earth Orbital Environments;
 Nutation Dampers;
 Spacecraft Stability;
 Laminar Flow;
 Mathematical Models;
 Nasa Space Programs;
 Reynolds Number;
 Spacecraft Instrumentation