Subject orientation on short-arm centrifuge

The short-radius centrifugation stimulus used during the DSO 635 study was patterned from a previous Spacelab experiment and consisted of rotation about an Earth-vertical axis in the pitch plane (left side down) with the interaural axis positioned 0.5m off-axis. Subjects were accelerated in darkness at 25°/s2 to a constant rate of 140°/s in either forward-facing or backward-facing directions for 60 seconds, followed by superimposed sinusoidal oscillation for one minute each in darkness, with a matched vertical optokinetic stimulation at the same frequency, and then again in darkness.