The ancient art of origami is generally linked to the folding of paper to obtain all kinds of shapes, the classic origami that we know in Europe, but it has many other possible applications. In recent years, various advances have been made in sectors as seemingly far-flung as aeronautics, furniture design and construction. took advantage of their foundations to propose innovative solutions to different problems. Examples of this are aluminum lattice structures to make lighter and stronger planes or the ingenious folding solar panels that can be placed in seconds to provide instant energy.
Its usefulness is based on the possibilities it offers for folding and unfolding structures, which is very useful in different sectors, in which ease of transport and great strength and rigidity once deployed are required. The latest advance in this area comes from Australia, where scientists from the University of Queensland and the Royal Melbourne Institute of Technology (RMIT) have developed a new tubular structural system. It is lightweight and can easily be transported completely flat when not in use and, when unfolded, automatically locks without human intervention to support approximately 60 times its weight.
In the study published in Proceedings of the National Academy of Sciences (PNAS) The manufacturing methods and functions of these structures are detailed with a “self-locking system resulting from intelligent geometric design”, according to Jeff Lee of the RMIT School of Engineering. “Our invention is suitable for large-scale use: a panel weighing only 1.3 kg made up of several tubes can easily support a 75 kg person“, he said in a press release.
How it works
Deployable tubular structures such as those developed by RMIT engineers are designed for further functional expansion and have a very wide range of applications, from flexible pipes to structural elements used in the aerospace sectorincluding temporary buildings to house victims of natural disasters or medical devices.
However, there are historically two elements that are not always balanced to optimize the performance of this type of structure, Expansion capacity and rigidity. Often, these structures must sacrifice themselves for each other: if they are too flexible, they cannot support much weight, and if they are too rigid, folding them does not reduce their size enough to make them easily transportable.
The team of researchers behind the tubular structures
Omicron
To resolve this conflict, the team led by Jeff Lee and Mike Xie They were inspired by the structure of bamboo and turned to origami-inspired curved pleat techniques to achieve maximum flexibility and rigidity. The key lies in the internal diaphragms which, when deployed, automatically lock to provide the necessary rigidity.
Bamboo, still used in construction and which can be twice as strong as concrete under certain conditions, is a natural material whose internal structures serve as reinforcement without losing flexibility. The RMIT team replicated this feature using a clever geometric design, in which the elastic buckling of the shell “hardens” when the structure is deployed.
“When NASA deploys solar panels, for example, The arms used are tubes packed flat before being deployed in space“, explains Lee. “Our new tubes, inspired by origami principles, could provide greater structural strength in various conditions.”
Manufacturing and applications
The prototypes’ flat shell and diaphragm components were precision laser cut from polyethylene terephthalate glycol (PETG) sheets, a type of plastic with a final thickness between 0.10 and 0.15 mm. Given its ease of scalability, they tested its performance with different component sizes, taking as an example the structure which weighs only 1.3 kg and can support 75 kg, or 57.6 times its weight.
Mike Xie (left) and Jeff Lee (right), lead authors of the tubular structures study
Omicron
To adapt each of the elements, they used a smart algorithm to study how tubes would behave under different forces. They thus verified that, if the orientation of the diaphragms is modified, the resistance and flexibility of the entire structure can be adapted to the specific needs of each moment.
“Thanks to our origami-inspired innovation, the flat tubes are not only easy to transport, but are also strong enough to resist external forces when in use,” explains Mike Xie. “In addition, the tube is self-locking, which means that its shape is firmly locked without requiring additional mechanisms nor human intervention.
Según señalan en su estudio, estos tubos tienen “aplicaciones potenciales en diversos campos en los que se emplean ampliamente las estructuras tubulares desplegables, como la biomedicina, la industria aeroespacial, la construcción y la robótica”. Para avanzar en su desarrollo y ampliar sus posibles funciones, el equipo está explorando el uso de nuevos materiales y distintos métodos de fabricación.
Entre los próximos pasos de su investigación, Lee comenta su intención de “ampliar la función de autobloqueo a otras formas de tubo y comprobar su comportamiento ante diversas fuerzas, como la flexión y la torsión“. El objetivo es hacerlos aún más versátiles y resistentes ante cualquier eventualidad.
