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Physiological Acceleration Systems

This table is incomplete

System 1 System 2 System 3 System 4 System 5
Verbal definition Pictorial description Descriptive terms Vernacular description
AGARD symbolsb Heart diplacement
Linear forces of acceleration
A force applied to the posterior part of the trunk acting forward with respect to the subject and perpendicular to the mean spine produces a forward acceleration Forward acceleration or forward acting force Eyeballs in +Gx Moves toward back Forward acceleration Transverse A-P G
Supine G
Chest to back G
Sternumward Surge
A force applied to the anterior part of the trunk acting backward with respect to the subject and perpendicular to the mean spine produces a backward acceleration Backward acceleration or backward acting force Eyeballs out -Gx Moves toward front Backward acceleration Transverse P-A G
Prone G
Back to chest G
Spineward -
A force applied to the left surface of the subjects body, acting in a rightward direction and essentially perpendicular to the subject's mean spin produces a rightward acceleration Rightward acceleration or rightward acting force Eyeballs left +Gy Moves toward left Right lateral acceleration Left lateral G - Left sway
A force applied to the right surface of the subject's body, acting in a leftward direction and essentially perpendicular to the subject's mean spine produces a leftward acceleration Leftward acceleration or leftward acting force Eyeballs right -Gy Moves toward right Left lateral acceleration Right lateral G - Right sway
A force applied to the buttocks, thighs, and or feet, acting in a headward direction with respect to the subject and essentially parallel to the subject's mean spine produces a headward acceleration Headward acceleration or headward acting force Eyeballs down +Gs Moves toward feet Headward acceleration Positive G Tailward -
A force applied to the shoulders, thighs, and feet of a seated human acting in a tailward direction with respect to the subject and essentially parallel to the subject's mean spine produces a tailward acceleration. Tailward acceleration or tailward acting force Eyeballs up -Gs Moves toward head Footward acceleration Negative G Headward Heave
Oscillatory forces or acceleration
Forces that alternate in direction and produce alternately forward and backward motion of the subject, and that act essentially perpendicular to the spine, produce front to back acceleration Front-to-back oscillating force or acceleration - +/- Gx Oscillates fore-and-aft within thorax - - - -
Forces that alternate in direction and produce alternately side to side motion of the subject, and that act essentially perpendicular to the spine, produce side to side acceleration Side-to-side oscillating force or acceleration - +/- Gy Oscillates side-to-side within thorax - - - -
Forces that alternate in direction and produce alternately head to tail motion of the subject, and that act essentially parallel to the spine, produce head to tail acceleration Head-to-tail oscillating force or acceleration - +/- Gs Oscillates head-to-tail within thorax - - - -
Angular moments or acceleration
A rotational moment or couple that produces a head left motion of the subject that lies essentially in the frontal (shoulder-to-shoulder) plane produces a head left cartwheeling angular acceleration Head left cartwheeling moment or acceleration - -Rx Top tilts toward right shoulder - - - -
A rotational moment or couple that produces a head right motion of the subject that lies essentially in the frontal (shoulder-to-shoulder) plane produces a head right cartwheeling angular acceleration Head right cartwheeling moment or acceleration - +Rx Top tilts toward left shoulder - - - -
A rotational moment or couple that produces a head-forward feet backward tumbling motion of the subject that lies essentially in the saggital plane produces a forward somersaulting angular acceleration Forward somersaulting moment or acceleration - -Ry Top tilts toward spine - - - -
A rotational moment or couple that produces a head-backward feet-forward tumbling motion of the subject that lies essentially in the saggital plane produces a backward somersaulting angular acceleration Backward somersaulting moment or acceleration - +Ry Top tilts toward sternum - - - -
A rotational moment or couple that produces a right-turn motion of the subject about the spine in the saggital plane produces a right twisting angular acceleration and will be named a right turn pirouetting force or couple Right twisting moment or acceleration - +Rs Twists toward subject's left - - - -
A rotational moment or couple that produces a left-turn motion of the subject about the spine in the saggital plane produces a left twisting angular acceleration Left twisting moment or acceleration - -Rs Twists toward subject's right - - - -

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