My research interests are centered on small-scale medical robots, acoustics, ultrasound and photoacoustic imaging, and lab-on-a-chip systems. In particular, my research thrusts focus on developing medical microrobots and microfluidic devices for biomedical applications by exploiting multiphysics computational modeling, advanced robot design and fabrication techniques, wireless actuation methods using acoustic and magnetic fields, microrobot tracking via ultrasound and photoacoustic imaging, and minimally-invasive medical interventions.
news
Oct 25, 2022
Our recent paper “Reduced rotational flows enable the translation of surface-rolling microrobots in confined spaces “ published in Nature Communications shows the effect of the physical confinements on the locomotion of surface-rolling microrobots.
Aug 11, 2022
Our paper “Piezo Capsule: Ultrasonic Way of Wireless Pressure Measurement” is published in Advanced Intellligent Systems. Here, we present the piezo capsule, a simple, cost-effective, and miniaturized passive ultrasound pressure sensing system. We demonstrated the real-time pressure profiles of an artificial vessel for varying fluid flow pulse frequency and volumetric rates.
Jun 29, 2022
I give an invited talk in the Micro/Nanorobots for Medicine workshop of Hamlyn Symposium on Medical Robotics 2022 at Imperial College, London. The talk title is “Trends in medical microrobotics: future outlook and challenges”.
May 12, 2022
Our science advances paper is highlighted in ETH news: “New imaging method makes tiny robots visible in the body”.
@article{bozuyuk2022reduced,title={Reduced rotational flows enable the translation of surface-rolling microrobots in confined spaces},author={Bozuyuk, Ugur and Aghakhani, Amirreza and Alapan, Yunus and Yunusa, Muhammad and Wrede, Paul and Sitti, Metin},journal={Nature Communications},volume={13},number={1},pages={6289},year={2022},doi={https://doi.org/10.1038/s41467-022-34023-z},publisher={Nature Publishing Group UK London},}
Sci. Adv.
High shear rate propulsion of acoustic microrobots in complex biological fluids
Untethered microrobots offer a great promise for localized targeted therapy in hard-to-access spaces in our body. Despite recent advancements, most microrobot propulsion capabilities have been limited to homogenous Newtonian fluids. However, the biological fluids present in our body are heterogeneous and have shear rate–dependent rheological properties, which limit the propulsion of microrobots using conventional designs and actuation methods. We propose an acoustically powered microrobotic system, consisting of a three-dimensionally printed 30-micrometer-diameter hollow body with an oscillatory microbubble, to generate high shear rate fluidic flow for propulsion in complex biofluids. The acoustically induced microstreaming flow leads to distinct surface-slipping and puller-type propulsion modes in Newtonian and non-Newtonian fluids, respectively. We demonstrate efficient propulsion of the microrobots in diverse biological fluids, including in vitro navigation through mucus layers on biologically relevant three-dimensional surfaces. The microrobot design and high shear rate propulsion mechanism discussed herein could open new possibilities to deploy microrobots in complex biofluids toward minimally invasive targeted therapy.
@article{aghakhani2022high,title={High shear rate propulsion of acoustic microrobots in complex biological fluids},author={Aghakhani, Amirreza and Pena-Francesch, Abdon and Bozuyuk, Ugur and Cetin, Hakan and Wrede, Paul and Sitti, Metin},journal={Science advances},volume={8},number={10},pages={eabm5126},year={2022},publisher={American Association for the Advancement of Science},}
PNAS
Acoustically Powered Surface-Slipping Mobile Microrobots
Amirreza Aghakhani, Oncay Yasa, Paul Wrede, and 1 more author
Proceedings of the National Academy of Sciences 2020
Untethered synthetic microrobots have significant potential to revolutionize minimally invasive medical interventions in the future. However, their relatively slow speed and low controllability near surfaces typically are some of the barriers standing in the way of their medical applications. Here, we introduce acoustically powered microrobots with a fast, unidirectional surface-slipping locomotion on both flat and curved surfaces. The proposed three-dimensionally printed, bullet-shaped microrobot contains a spherical air bubble trapped inside its internal body cavity, where the bubble is resonated using acoustic waves. The net fluidic flow due to the bubble oscillation orients the microrobot’s axisymmetric axis perpendicular to the wall and then propels it laterally at very high speeds (up to 90 body lengths per second with a body length of 25 µm) while inducing an attractive force toward the wall. To achieve unidirectional locomotion, a small fin is added to the microrobot’s cylindrical body surface, which biases the propulsion direction. For motion direction control, the microrobots are coated anisotropically with a soft magnetic nanofilm layer, allowing steering under a uniform magnetic field. Finally, surface locomotion capability of the microrobots is demonstrated inside a three-dimensional circular cross-sectional microchannel under acoustic actuation. Overall, the combination of acoustic powering and magnetic steering can be effectively utilized to actuate and navigate these microrobots in confined and hard-to-reach body location areas in a minimally invasive fashion.
@article{aghakhaniAcousticallyPoweredSurfaceslipping2020a,title={Acoustically Powered Surface-Slipping Mobile Microrobots},author={Aghakhani, Amirreza and Yasa, Oncay and Wrede, Paul and Sitti, Metin},year={2020},date={2020-02-18},journal={Proceedings of the National Academy of Sciences},shortjournal={Proc Natl Acad Sci USA},volume={117},number={7},pages={3469--3477},issn={0027-8424, 1091-6490},doi={10.1073/pnas.1920099117},url={},urldate={2021-04-14},langid={english}}
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