Mechanical and fluid system and method for the prevention and control of motion sickness, motion-induced vision sickness, and other variants of spatial disorientation and vertigo

A non-electronic system for providing visual orientation information, the system comprising:

• a head attachment unit configured for attachment to a head of a person;
• an optical element selected from the group of a lens, a mirror, a beam splitter, and a prism wherein the optical element is configured to be visible to the person;
• an orientation reference symbol configured to be visible to the person when viewing the optical element, wherein:
• the symbol is fixedly coupled to movement of the head attachment unit whereby the symbol is configured to be in a fixed visual position for the person when the person's head moves;
• and
• the symbol comprises a reference element selected from the group of a pitch reference element and a roll element;
• an indicator selected from the group of a pitch indicator and a roll indicator, wherein:
• the indicator is configured to be visible to the person when viewing the optical element;
• the indicator moves in response to rotation of the head attachment unit about an orientation selected from the group of an interaural axis and a naso-occipital axis of the person;
• the indicator is responsive to an inertial device selected from the group of a pendulum attached to the unit, a rolling element retained in the unit, and two fluids in a reservoir in the unit;
• movement of the indicator does not comprise a response from an electro-mechanical sensor selected from the group of an accelerometer, a gyroscope, an acoustic detector, a magnetic detector, and an optical detector;
• and
• movement of the indicator does not require the use of electricity;
• and
• movement of the indicator occurs in a normal field of view of the person.