Robots are extensively used to paint airplanes, make cars, and sew clothing in factories. However, the assembly of microscopic components, for example, those used for biomedical applications, is yet to be automated.
Lasers could offer a solution to this problem. Scientists have now used lasers to develop miniature robots using bubbles that lift, drop, and control tiny pieces into interconnected structures. The study results have been published in the ACS Applied Materials & Interfaces journal.
With the miniaturization of manufacturing, objects with a length only a few hundred micrometers, or about the thickness of a sheet of paper, are now being developed. However, it is challenging to assemble such tiny pieces by hand.
In earlier studies, researchers developed microscopic bubbles with sound or light to position 2D items. Moreover, as part of a latest experiment, microbubbles created by lasers—powerful, focused beams of light—could rotate shapes in 3D space.
These bubble microrobots were able to control 2D and 3D objects but could not connect individual components and eventually move them as a singular entity. There, Niandong Jiao, Lianquing Liu, and their team intended to advance their previous studies with lasers to create bubble microbots with the ability to form inseparable shapes and manipulate their movement.
The researchers focused a laser underneath a small part made of resin to make microbubbles in water. The size of the bubbles was manipulated by quickly turning the laser on and off, with a higher amount of time in the “on position” leading to larger bubbles. Next, the researchers developed a mobile bubble robot by shifting the location of the laser.
Once the laser was switched off, the bubbles gradually dissolved, thus dropping the resin in place. Then, the researchers integrated multiple bubbles with various functions to create microrobots that could lift and drop parts, shift single pieces to desired positions, serve as a rotational axis, or push assembled objects.
Different joints were used to create unbreakable connections, generating three- and four-pronged gears, a miniature 3D vehicle, and a snake-shaped chain. According to the researchers, the bubble microrobots are promising for the future of manufacturing, such as for biological tissue engineering.
This study was financially supported by the National Natural Science Foundation of China, the Key Research Program of Frontier Sciences of the Chinese Academy of Sciences, and the CAS/SAFEA International Partnership Program for Creative Research Teams.
Video Credit: American Chemical Society.
Dai, L., et al. (2020) Integrated Assembly and Flexible Movement of Microparts Using Multifunctional Bubble Microrobots. ACS Applied Materials & Interfaces. doi.org/10.1021/acsami.0c17518.