Researchers at the FAMU-FSU College of Engineering and the Florida State University-headquartered National High Magnetic Field Laboratory have developed a novel design for a low-gravity simulator. The new design can create an area of low gravity with a volume about 1,000 times larger than existing simulators of the same type, paving the way for breakthroughs in space research.
‘Low gravity has a profound effect on the behaviours of biological systems and also affects many physical processes, from the dynamics and heat transfer of fluids to the growth and self-organisation of materials,’ said Wei Guo, associate professor in mechanical engineering and the study’s lead scientist. ‘However, spaceflight experiments are often limited by the high cost and the small payload size and mass. Therefore, developing ground-based low-gravity simulators is important.’
Existing simulators, such as drop towers and parabolic aircraft, use free fall to reduce the effect of gravity, but can only generate for several seconds to a few minutes at a time, making them unsuitable for experiments that require long observation times.Magnetic levitation-based simulators (MLSs), on the other hand, can offer practically unlimited operation times, along with other advantages such as a reduced cost, easy accessibility and more precisely adjustable levels of gravity.
Conventional MLSs can only create a small volume of low gravity – typically only a few micro-litres for an environment that’s about one per cent of Earth’s gravity – which is too small for practical space research and applications. The researchers found that they could significantly increase the functional volume using a magnet created by integrating a superconducting magnet with a gradient Maxwell coil – a coil configuration that was first proposed during the 19th century by physicist James Clark Maxwell.
‘Our analysis shows that an unprecedented functional volume of more than 4,000 microlitres can be achieved in a compact coil with a diameter of only eight centimetres,’ said doctoral student Hamid Sanavandi, who also worked on the research. ‘When the current in the MLS is reduced to emulate the gravity on Mars, the functional volume can exceed 20,000 microlitres, or about 20 cubic centimetres.’
The researchers also showed how the MLS can be made using existing high-temperature superconducting materials, enabling it to operate with minimal energy consumption.
‘The fact that our MLS design offers a functional volume about three orders of magnitude larger than that for conventional solenoid MLSs makes it a potential game-changer in the low-gravity research field,’ Guo said. ‘When this MLS design is used to emulate reduced gravities in extra-terrestrial environments, such as on the moon or Mars, the resultant functional volume is large enough to accommodate even small plants, making this an exciting tool for medical and biological research.’
The results of the research have been published in npj Microgravity.