April 24, 2024

Combining Robotics and Microfluidics: A Precision Arm for Miniature Robots

Utilizing a glass needle made to oscillate with the assistance of ultrasound, liquids can be controlled and particles can be caught. Credit: ETH Zurich
The majority of us are familiar with robots that have movable arms. These devices are commonly discovered in factory settings and are capable of carrying out various mechanical tasks. They can be set to carry out a range of functions, and a single robotic can perform multiple jobs.
Up up until now, robots geared up with movable arms have actually had limited connections with microfluidic systems that carry tiny amounts of liquid through fragile capillaries. These systems, known as microfluidics or lab-on-a-chip, were created by researchers to help in lab analysis and typically rely on external pumps to circulate the liquid through the chips. Automating such systems has been challenging, and the chips had to be custom-made and made for each individual application.
Ultrasound needle oscillations
Scientists led by ETH Professor Daniel Ahmed are now combining conventional robotics and microfluidics. They have actually established a gadget that uses ultrasound and can be connected to a robotic arm. It is ideal for carrying out a wide variety of jobs in microfluidic and microrobotic applications and can likewise be utilized to automate such applications. The scientists have actually reported on this development in Nature Communications.

The gadget comprises a thin, pointed glass needle and a piezoelectric transducer that triggers the needle to oscillate. By dipping the needle into a liquid they develop a three- dimensional pattern composed of multiple vortices. “However, our technique prospers in doing this because it allows us to not just produce a single vortex but to likewise effectively blend the liquids utilizing a complicated three- dimensional pattern composed of multiple strong vortices.”
Relatively big particles move towards the oscillating glass needle, where they build up. The scientists would next like to combine numerous glass needles to create even more complex vortex patterns in liquids.

The device consists of a thin, pointed glass needle and a piezoelectric transducer that causes the needle to oscillate. Comparable transducers are utilized in speakers, ultrasound imaging, and professional oral cleansing equipment. The ETH researchers can differ the oscillation frequency of their glass needles. By dipping the needle into a liquid they develop a three- dimensional pattern composed of several vortices. Since this pattern depends upon the oscillation frequency, it can be managed appropriately.
“The more viscous liquids are, the more tough it is to mix them,” Professor Ahmed discusses. “However, our approach succeeds in doing this since it allows us to not only create a single vortex but to likewise efficiently mix the liquids utilizing an intricate 3- dimensional pattern composed of multiple strong vortices.”
Second, the researchers had the ability to pump fluids through a mini- channel system by creating a particular pattern of vortices and putting the oscillating glass needle near to the channel wall.
Third, they succeeded in utilizing their robot- assisted acoustic device to trap fine particles present in the fluid. Fairly large particles move toward the oscillating glass needle, where they accumulate. The scientists showed how this method can capture not only inanimate particles but likewise fish embryos.
” Until now, developments in large, microfluidic applications and standard robotics have actually been made separately,” Ahmed states. “Mixing and pumping liquids and trapping particles– we can do it all with one gadget,” Ahmed says. The researchers would next like to combine a number of glass needles to produce even more complex vortex patterns in liquids.
In addition to laboratory analysis, Ahmed can envisage other applications for microrobotic arms, such as sorting tiny things. The arms could conceivably likewise be used in biotechnology as a method of presenting DNA into specific cells. It needs to eventually be possible to employ them in additive manufacturing and 3D printing.
Referral: “A robot-assisted acoustofluidic end effector” by Jan Durrer, Prajwal Agrawal, Ali Ozgul, Stephan C. F. Neuhauss, Nitesh Nama and Daniel Ahmed, 26 October 2022, Nature Communications.DOI: 10.1038/ s41467-022-34167-y.