Flight test of an international space station active rack isolation prototype system

Space flight experiment test results of a prototype space station Active Rack Isolation System (ARIS) are presented. The purpose of ARIS is to isolate microgravity sensitive science experiments mounted in the International Standard Payload Rack (ISPR) from the structural vibrations present on the large space station orbital structure. Space flight testing was necessary because ARIS cannot be tested in all six degrees-of-freedom simultaneously on the ground. The foremost objectives of the experiment were (1) to determine if the system would be stable when all six axis are controlled, (2) to determine if the systems position response to accelerometer drift would result in excessive motion, (3) to measure isolation performance and determine the impact of attaching umbilicals, and (4) to measure the quiescent background acceleration levels induced by the controller itself. Results related to these objectives are presented along with a description of the control architecture. A brief historical perspective, a description of ARIS, and a flight test summary are also presented.