Spanish researchers from the Universidad Carlos III de Madrid are in the process of developing an innovative magnetic levitating transmission mechanism that could advance space travel and exploration as well as the railroad and aircraft industries.
The university’s research is based on the endeavor of MAGDRIVE – a continental project from the Space area of the European Union’s Seventh Framework Programme – coordinated by Professor José Luis Pérez Díaz, from the UC3M Instituto Pedro San Juan de Lastanosa, and includes inputs and investments from seven European entities.
According to the researchers, the novel transmission system consists of the development of a magnetic gear reducer – a mechanism that transforms speed from an input axle to another in an output axle, as in a bicycle chain mechanism or the gearbox of an automobile. But in the new gear’s case – unlike a conventional gear reducer – the transmission is produced without contact between the pieces thanks to the magnetism.
One of the chief advantages of this new gear is the absence of wear among the pieces, which makes lubrication unnecessary. As such, “the operating life of these devices can be much longer than the life of a conventional gear reducer with teeth, and can even work in cryogenic temperatures,” notes one of the researchers, Efrén Díez Jiménez, from the UC3M Department of Mechanical Engineering.
It can even continue to function after an event of overload. If the axle is blocked, the parts simply slide amongst themselves, but nothing breaks. Moreover, less noise is produced, vibration is reduced, and it is capable of through-wall transmission.
In addition to the contactless transmission, the axles are likewise contactless: “It is the first time in history that the input axle as well as the output axle of a gear reducer are floating without any kind of contact, and it can keep a mechanism which contains nothing else spinning at 3,000 revolutions per minute at cryogenic temperatures” says project lead, José Luis Pérez Díaz.
Although the main goal of the MAGDRIVE project was to build a single prototype meant for extreme conditions in outer space, it resulted in the birth of another best suited for room temperature applications.
The cryogenic prototype developed for outer space keeps the axles floating and it can work at a temperature of -210°C and in a vacuum. The mechanism integrates levitating superconductor bearings that generate stable forces of repulsion into its structure. This allows it to turn and, moreover, it stabilizes it against oscillating motion or possible imbalances. According to the project researchers, it is the first mechanism in history that does not have this type of friction.
The second prototype that can be used at room temperature features a magnetic reducer which “substitutes the gear teeth with permanent magnets that repel and attract each other” so that “the transmission of couples and forces between the moving parts with contact is achieved,” explains Jiménez.
Its applications can be transferred to any field where conventional mechanical reducers are used, such as self-propulsion, the railroad sector, the oil industry, or in mechanics and manufacturing in general, cite the researchers. Thanks to the absence of lubrication and oils, it can also be applied in the pharmaceutical, biomedical and food industries, where cleanliness requirements are very strict.
Although the cryogenic prototype was the global objective of the project because it solved the problem posed by the European Space Agency (ESA), the researchers conclude that the room temperature prototype is the one that can have the biggest impact on industrial applications.
Image courtesy of UC3M
