AAS 95-387

Demonstration of Autonomous Orbit Determination Around Small Bodies

S. Bhaskaran and J. E. Riedel, Jet Propulsion Laboratory, Pasadena, CA

Abstract

An important component of future space missions is to examine small solar system objects such as asteroids or comets with inexpensive spacecraft. In order to reduce the costs of such missions, it is desirable to perform some or all of the navigation function onboard the spacecraft. This paper presents and algorithm to autonomously determine the orbit of the spacecraft using a wide field-of-view camera and a precomputed model of the object. In the algorithm, the observed limbs of the object are compared with its precomputed location using the model to obtain an instantaneous position fix of the spacecraft. A series of these position fixes are then input to a filter which determines the complete state of the spacecraft. The procedure is validated using simulations of orbits around sample asteroids.