Free Fall Machine

The Free Fall Machine (FFM) is an apparatus that provides simulated microgravity for long duration experiments. The system is based on the principle of free fall. The free fall periods in the FFM is at maximum around 900 ms and is interrupted by a acceleration of about 20 × g for about 20-80 ms.

The FFM simulation is based on the hypothesis developed by Dr. Dick Mesland, that systems may experience the FFM as a continuous free fall condition if the gravity perception time of the system is shorter than the intermediate period of 20-80 ms of 20 × gravity. Systems might have 'gravity sensitive windows'. The working principle of a FFM is exactly the same as that of a parabolic aircraft only the time courses are different.

The core of the facility is a vertical bar which guides the experiment while it goes through its free fall cycles. A control centrifuge, generating 1 × g, is integrated into the system and operated while under free fall conditions.


Free Fall Machine in closed and opened temperature controlled room.


Free Fall Machine main control panel.
Future experiments on the FFM could make use of developments that have taken place within the Technology Development Program at ESA/ESTEC. Various hardware items for gravitation biology, such as small microscopes, video cameras, cell / tissue culture modules, insect modules etc., have been developed. These modules might be used on the Free Fall Machine to investigate how biological systems will respond to simulated microgravity. See the ESA web site for detailed information on these items, or contact DESC for their use on the FFM (or RPM / MidiCAR centrifuge).

All facilities mentioned are open to perform your individual, dedicated, experiments or for collaborative studies. When you are interested to perform a series of (pilot) studies using the FFM you are invited to contact us to discuss various possibilities. You may also directly send an experiment proposal either to DESC or respond to one of the international 'Announcements of Opportunities' (AO) as are in general annually issued by the European Space Agency (ESA) or other space agencies. You may also apply via an unsolicited proposal to ESA via the 'fast track' Continuously Open Research Announcements. You may contact us when you need any support for this. Dutch scientists may also apply nationally via a a NSO-NWO proposal. An additional copy of the proposal has to be provided to DESC for technical and operational evaluations.

FFM Detailed Description
  • The FFM is accommodated in a temperature-controlled incubator ranging from +4 to +40 °C.
  • Cycle time: maximum 900 ms, reverse time 20-80 ms. Total free fall time is 86 to 98%.
  • PC user interface with dedicated control software
  • On line data collection of facility performance
  • Operational modes: free fall and free fall with 1 × g centrifuge
  • Control experiment with same interfaces may be placed in same environment
  • Experiment interfaces:
  • Switchable 5 / 12 volt power line
  • Maximum experiment mass to be accommodated 2 × 750 gram.
  • Maximum experiment dimensions: 80 ×150 × 60 mm (h×w×d)
  • Core system dimensions 2150 × 600 × 600 mm (h×w×d)
  • Main dimensions temperature device 6650 × 314 × 483 mm (h×w×d)


See for additional information on FFM (and RPM) the ESA publication by D. Mesland. Experiment on mammalian cells are conducted by Schwartzenberg et al.: 'Signal transduction in T lymphocytes - A comparison of the data from space, the free fall machine and the random positioning machine' in Adv. Space Res. 24, 793-800, 1999.

The Free Fall Machine is developed by CCM Nuenen, in The Netherlands.

Go to the INDEX page