Technology and Developments for the Random Positioning Machine, RPM

Abstract

A Random Positioning Machine (RPM) is a laboratory instrument to provide continuous random change in orientation relative to the gravity vector of an accommodated (biological) experiment. The use of the RPM can generate effects comparable to the effects of true microgravity when the changes in direction are faster than the object's response time to gravity. Thus, relatively responsive living objects, like plants but also other systems, are excellent candidates to be studied on RPMs. In this paper the working principle, technology and control modes will be explained and an overview of the previously used and available experiment systems will be presented. Current and future developments like a microscope facility or fluid handling systems on the RPM and the option to provide partial gravity control modes simulating for instance Mars or Moon gravity will be discussed.

Simulation of Microgravity by Magnetic Levitation and Random Positioning: Effect on Human A431 Cell Morphology

“…The Random Positioning Machine (Hoson et al 1992(Hoson et al , 1997van Loon 2007;Borst and van Loon 2009) is based on the principle that the direction of gravity is randomized in three dimensions. Rotation in three dimensions with varying speeds is required to provide truly three dimensional random motion (Borst and van Loon 2009).…”

Patterning of plant cell wall deposition by cortical microtubules

“…The RPM consists of two independent frames that rotate randomly in order to continuously change the direction of the gravity vector 105,106 . The rotation direction and speed of the RPM frames changes randomly with a maximum rotation speed of ±60° sec -1 .…”

Final report SI 08-SI-004: Fusion application targets

“…We therefore decided to design a random position machine (RPM) 22 that provides a deterministic, continuous random change in orientation relative to the gravity vector thus simulating a true microgravity environment. This can be achieved by a system that uses two perpendicular and independently driven frames.…”