On-orbit spacecraft servicing has become a realistic and promising space mission. The Autonomous Docking and Spacecraft Servicing Simulator (AUDASS), introduced in this paper, is a research facility for on-the-ground testing of proximity navigation, docking and satellite servicing technologies and for the experimental verification of dynamics models and control laws. Moreover, the test-bed constitutes a valuable educational tool for the university students directly involved in its design and exploitation. This paper presents the current status of the on-going development of the AUDASS simulator and reports the results of some preliminary tests. The AUDASS system consists of two independent robotic vehicles, a chaser and a target. The vehicles float, via air pads, on a polished granite table providing a frictionless support for the simulation in 2-D of the micro-gravity dynamics. The introduction of the paper provides a wide overview of the on-going research efforts to make autonomous docking and servicing of spacecraft a reality.
Space based bifocal relay mirrors are potentially an enabling/enhancing piece of any architecture making use of long-range laser propagation. Inherent in the bifocal concept is dual line of sight control. This is especially challenging in this space-based application due to spacecraft attitude control issues. This paper presents a summary of the research into acquisition, tracking, pointing (ATP) and control technologies relevant to a bifocal relay mirror system as well as the development of a laboratory experimental test bed to integrate the advanced optics systems onto a Three-axis spacecraft simulator. The relay geometry includes a cooperative source and either a cooperative or non-cooperative target depending on the application. The described test bed is a joint effort with the Air Force Research Laboratory (optics) and the Naval Postgraduate School (spacecraft simulator).