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Van Der Ha J.,5808 Bell Creek Road | Mimasu Y.,Japan Aerospace Exploration Agency | Tsuda Y.,Japan Aerospace Exploration Agency | Mori O.,Japan Aerospace Exploration Agency
Journal of Spacecraft and Rockets | Year: 2015

This paper gives a detailed evaluation of the solar and thermal radiation accelerations acting on the IKAROS spacecraft consisting of a solar sail and a central body during its operational mission from June to December 2010. In particular, the predicted temperatures are compared with actual in-flight measurementsonthe sail membrane and on the body. The results show good correspondences in most cases, but a few appreciable deviations have been observed as well. The simulation results indicate that the magnitude of the thermal radiation perturbations on the solar sail trajectoryis below1%ofthose inducedby the solar radiation. The accelerations causedby the thermal radiation turn out tobe insignificant because their magnitudes are within the rangeofuncertaintyof the accelerations inducedbythe solar radiation forces. Copyright © 2015 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.

Janssens F.L.,Wilhelminastraat 29 | Van Der Ha J.C.,5808 Bell Creek Road
Acta Astronautica | Year: 2014

This paper considers a spinning rigid body and a particle with internal motion under axial thrust. This model is helpful for gaining insights into the nutation anomalies that occurred near the end of orbit injections performed by STAR-48 rocket motors. The stability of this system is investigated by means of linearized equations about a uniform spin reference state. In this model, a double root does not necessarily imply instability. The resulting stability condition defines a manifold in the parameter space. A detailed study of this manifold and the parameter space shows that the envelope of the constant solutions is in fact the stability boundary. Only part of the manifold defines a physical system and the range of frequency values that make the system unstable is restricted. Also it turns out that an increase of the spring stiffness, which restrains the internal motion, does not necessarily increase the stability margin. The application of the model is demonstrated using the orbit injection data of ESA's Ulysses satellite in 1990. © 2012 Elsevier B.V. All rights reserved.

Janssens F.L.,Wilhelminastraat 29 | van der Ha J.C.,5808 Bell Creek Road
Acta Astronautica | Year: 2015

The recovery from a flat-spin motion represents one of the most impressive practical applications in the field of spinning-satellite dynamics. The present paper presents flat-spin recovery maneuvers by means of a body-fixed torque within the plane perpendicular to the maximum principal axis of inertia. The conditions for a successful recovery are established. These are quite different from those obtained in the case when the torque is along the minimum axis of inertia where a minimum torque level is required for a successful recovery. If the torque component along the intermediate axis is negative, a recovery from a pure flat spin can be established for any torque magnitude. However, the time to recovery increases indefinitely when this torque component approaches zero. During the recovery maneuver, the angular velocity and angular momentum vectors become aligned with the minimum axis of inertia by turning over about 90° in the body frame. In inertial space, however, the angular momentum stays in the vicinity of its orientation before the start of the recovery. © 2015 IAA.

Janssens F.L.,Wilhelminastraat 29 | Van Der Ha J.C.,5808 Bell Creek Road
Journal of Guidance, Control, and Dynamics | Year: 2015

The paper extends and clarifies the stability results for a spinning satellite under axial thrust in the presence of internal damped mass motion. It is known that prolate and oblate satellite configurations can be stabilized by damped mass motion. Here, the stability boundaries are established by exploiting the properties of the complex characteristic equation and the results are interpreted in terms of the physical system parameters. When the thrust level is the only free parameter, both prolate and oblate satellites can be stabilized provided that the thrust is within a specified range. This result is in contrast to the well-known maximum-axis rule for a free spinner where damping is always stabilizing (destabilizing) for an oblate (prolate) satellite. When adding a suitable spring-mass system, the minimum value of the spring constant that stabilizes the configuration can be established. In practice, however, the damping may well be too weak to be effective. Numerical illustrations are presented for the actual parameters of the Ulysses prolate configuration at orbit injection as well as for a fictitious oblate system. Finally, a new derivation of a previously established first integral for the undamped system is offered and its properties as a Lyapunov function are discussed. Copyright © 2014 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.

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