The Artificial Gravity Platform (AGP); a Very Large Radius Centrifuge as Human Hypergravity Habitat

Why would we need a large human rated centrifuge? Understanding the impact of temperature on human physiology one explores body responses to both at high and low temperature environments. Exploring gravity should not be any different. Understanding the impact gravity on humans we need to expose humans to low gravity (using ISS) and high gravity (using centrifuges). To date there have not been any studies reporting on long duration (weeks-months) exposure of humans to more than 1g. From previous space flight programs such as Apollo, Salyut, Mir and ISS we have gained valuable knowledge on how the human body adapts to microgravity, and as such on basic human physiology and psychology. Knowledge on high g environments is mainly driven by military/fighter pilot operations and training going up to levels as much as 9 g’s for very short times. There are few reports where humans have been exposed to (slightly) enlarged g for periods of hours or at most a few days. The latter studies were mainly related to vestibular investigations but little or no information has been reported on other organs or functions. However, numerous long duration hypergravity studies have been performed on animals. Chickens, mice, rats, dogs, rabbits, turtles, snails and many more species have been exposed to continuous hypergravity for weeks, months or even over a year. These studies have provided important information on the adaptation to higher accelerations. The obvious targets were the vestibular and musculoskeletal system, but also the immune and cardiovascular system show clear plasticity to a hypergravity environment. The last decade has seen increasing interest in the application of chronic acceleration in the study of neuroplasticity, metabolism, general animal behavior and cognitive function. Hypergravity increases bone and specific muscle masses. Otoconia size changes and in nearly all these long duration studies, hypergravity reduces fat mass in animals. Such an observation provides an important clue to explore sustained hypergravity in humans in light of the current societal issue like obesity and ageing. This paper presents the initiative of a large multidisciplinary group of scientists and engineers geared towards the possibility of developing and implementing a very large radius human centrifuge. The system should be used for physiological, psychological and operational studies, e.g. for the application of large in-flight rotating platforms for long duration missions, but may also be applied as test bed for e.g. Life Support Systems, or as Coriolis platform. We should also explore future operational parameters like partial pressure and hypoxic environments. The AGP / H3 should be such that a group of 6-12 persons (TBD) are exposed to a mild but constant hypergravity environment for weeks or months. Current estimates foresee a centrifuge with a diameter of 150 to 200 meters.