Assemble parts using acoustic levitation

Researchers have developed a novel system for assembling parts using acoustic levitation.

“LeviPrint is a system for assembling objects without contact, through acoustic manipulation. We generate acoustic fields that trap tiny particles, glue droplets, and most importantly, elongated stick-like elements that can be manipulated and reoriented while levitating. In short, it is a fully functional system for fabricating 3D structures using non-contact manipulation.” This is explained by Asier Marzo and Iñigo Ezcurdia, researchers at the Public University of Navarra (UPNA) in Spain, who together with Rafael Morales (Ultraleap Ltd, United Kingdom) and Marco Andrade (University of Sao Paulo, Brazil) are authors of a study entitled “LeviPrint: Contactless Fabrication using Full Acoustic Trapping of Elongated Parts”.

This research will be presented publicly in August in Vancouver (Canada) at SIGGRAPH, the most important conference on computer graphics and interactive techniques where companies such as Nvidia, Disney Research or Facebook Reality Labs present their work.

According to Asier Marzo, principal investigator and member of the UPNA Smart Cities Institute (ISC), “we have designed a levitator integrated with a robotic arm and a liquid dispenser to manufacture complex objects without contact.” Unlike ordinary assembly and manufacturing techniques, where parts are in direct contact with the machine, these researchers use acoustic manipulation to position and orient parts without touching them in assembly processes. “We can handle small and fragile parts, as well as liquids or powder, providing more versatility to the processes. There is less cross contamination as the handler does not touch the material. In addition, it allows manufacturing techniques that cannot be achieved with traditional 3D printing, such as adding elements to existing parts or manufacturing inside closed containers from the outside,” says Iñigo Ezcurdia, doctoral student and lead author of the research.

Structure created only with liquid hardened by ultraviolet rays. (Photo: UPNA)

novel contributions

As they explain, “the levitation and manipulation of small particles and drops had been achieved before, but there was no work on how to trap elongated objects in position and orientation; This research allows the use of segments, sticks or beams to manufacture robust, light and complex structures quickly and without contact”.

Some of the proposed techniques use a special glue that is liquid and solidifies with ultraviolet light. Although it is also possible to manufacture pieces that are composed only of glue, normally the structures are made by assembling particles and elongated segments with this glue. For example, the system catches with the acoustic levitator a drop of glue dispensed by a syringe. The drop is levitated to the position where the next piece will be added (assembled). The system collects a segment or particle, positions it next to the previous ones and ultraviolet light is used to dry the glue and join the new piece to the structure.

The ultrasonic field can pass through fabric, mesh, and other materials. For example, the researchers built a ship inside a metal-mesh bottle, non-contactly introducing materials from the outside through a small opening. “If Leviprint were adapted to work in aqueous media -they indicate-, it could assemble complex structures in cell culture media and perhaps even inside living beings”. (Source: UPNA)