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Simulators and simulations are both important to the study and alleviation of motion sickness. Motion sickness is generally the result of disagreement between what the eyes see and what the vestibular system (ears) senses. The well known symptoms range from lethargy to severe nausea. Beyond the discomfort is an associated degradation in performance - a problem for sailors at sea, troops riding in armored transports, airborne radar operators, and those rehearsing missions in simulators at sea. Recent U.S. Army studies of troops riding as passengers in armored vehicles indicate that up to a third of troops are sufficiently disoriented to be combat ineffective for a short period of time upon disembarking. While some is known about the causes of motion sickness, few remedies exist that are not based on performance degrading drugs or devices that are not effective for large segments of the population. We build special purpose simulators to generate motion sickness and simulations to study and alleviate its effects.
A typical motion sickness study subjects individuals to motion and various palliatives. Interviewers examine each subject and rate motion sickness on an established scale. These studies are conducted in conjunction with the Office of Naval Research, DARPA, and Brandeis and Clemson Universities.
A child spinning in circles knows you don’t need 6 degrees of freedom to generate motion sickness. One degree of freedom is sufficient if motion is approximately 0.2 Hz and acceleration above 0.1 g’s. Since human subjects are involved, safety is an overriding concern and existing devices are expensive to build, operate, and maintain.
 Our single degree of freedom device plays motion or torque profiles to rock a subject at up to +45 degrees at .25 hertz. We strap the subject into an aircraft seat with a 4-point harness and they perform a task while viewing a simulation on an LCD screen or a head-mounted display. The system rocks back and forth until the subject feels uncomfortable (their choice) or the task is completed.
 Artis built a larger motion platform with additional degrees of freedom, higher accelerations and greater maximum speeds. It can pitch-and-roll or pitch-and-yaw a subject with either a predefined motion profile (ship) or real-time user control (flight simulator). The roll and pitch axes can accelerate up to 90°/second2 and the yaw axis up to 180°/second2. Since it can spin along any powered axis it can also be used as an acrobatic flight simulator.
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