Free fall machine

A free fall machine (FFM) is a mechanism designed to permit the development of small biological samples, such as cell cultures, with a simulated effect of micro-gravity under free fall conditions.^[1]

Free fall machine

Acronym	FFM
Uses	Allows biological samples to develop in free fall, thus mitigating the effect of gravity.
Inventor	D. Mesland
Related items	Clinostat, Random positioning machine, Large diameter centrifuge

Description

The free fall machine (FFM) addresses some of the problems of the simple horizontal clinostat or random positioning machines (RPM). In a typical machine samples are allowed to cycle between free fall for about a metre down a column (micro-gravity simulation, near "0 g") and a "bounce" back to the top of the column that is intended to be so fast (c. 20 g for 20 ms) that it is undetected by the biological sample. Long duration of hyper-gravity is often simulated by machines such as the large diameter centrifuge (LDC) at ESA. To simulate partial-gravity (between simulated 0 and Earth's gravity, 1, such as Mars or Moon gravitational strengths) conditions, an RPM can also be used. The sample therefore effectively grows at near 0 g.

See also

• Gravitropism
• Large Diameter Centrifuge
• Random Positioning Machine
• Clinostat