Precise manipulations for micro/nano targets of synthetic particles and bio‐cells hold great promise for the next generation of nano robotic systems and micro‐machines. Although considerable efforts have been devoted to developing propulsion protocols for micro/nano‐manipulation, the limited intelligence without effective control for current microrobots prohibits them away from most sophisticated applications. Here, a novel approach integrating the vision feedback control (VFC) is presented into a microrobotic platform powered by acoustic fields to accomplish autonomous targets identification and optimization of the locomotion resolution. Driven by local enhanced acoustic streaming, microparticles in the vicinity of the linear manipulator could be transported along the given pathway. Via vision feedback control, the targets of microparticles are automatically recognized in the acousto‐microrobotic interface and driven toward the exact user‐defined destinations. The VFC integrated interface is also adoptable to multiple particle manipulations, where each particle is distinguished with unique index numbers for a convenient on‐demand selection. At last, this closed‐loop interface is validated to control the motion of bio‐cells, illustrating the good robustness and biological compatibility. The VFC based control strategy for acousto‐microrobotic interface is featured with favorable controllability and thus will have great potentials in myriad scenarios for smart micro/nano systems.

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Background: Combined with thrombolytic drugs and/or microbubbles, ultrasound (US) has been regarded as a useful tool for thrombolysis treatment by taking its advantages of noninvasive, non-ionization, low cost, and accurate targeting of tissues deep in body. Recently, low-intensity pulsed US, which can cause fewer complications by stable cavitation and acoustic streaming other than more violent effects, has attracted broad attention. Purpose: However, the thrombolysis effect in practice might not achieve expectation because there is not an ideal parallel multilayered structure between the skin and the targeted vessel. Therefore, the current work aims to better elucidate the influence of US incident angle on the generation of acoustic streaming and thrombolysis effect. Methods: Systemic numerical and experimental studies, namely, finite element modeling (FEM), particle image velocimetry (PIV), and in vitro thrombolysis measurements, were performed to estimate the acoustical/streaming field pattern, maximum flow velocity, and shear stress on the surface of thrombus, as well as the lysis rate generated at different conditions. These methods aim at verifying the hypothesis that streaming-induced vortices can further accelerate the dissolution of the thrombus and optimized thrombolysis effected can be achieved by adjusting US incident angles. Results: The pool data results showed that the variation trends of the flow velocity and shear stress obtained from FEM simulation and PIV experiments are qualitatively consistent with each other. There exists an optimal incident angle that can maximize the flow velocity and shear stress on the surface of thrombus, so that superior stirring and mixing effect can be generated. Furthermore, as the flow velocity and shear stress on thrombus surface are both highly correlated with the thrombolysis effect (the correlation coefficient R1 = 0.988, R2 = 0.958, respectively), the peak value of lysis rate (increase by at least 5.02%) also occurred at 10 • . Conclusions:The current results demonstrated that, with appropriately determined incident angle, higher thrombolysis rate could be achieved without increasing the driving pressure. It may shed the light on future US thrombolysis planning strategy that, if combined with other advanced technologies (e.g., machine-learning-based image analysis and image-guided adaptive US emission modulation), more efficient thrombolytic effect could be realized while minimizing undesired side-effects caused by excessively high pressure. K E Y W O R D Sacoustic streaming, finite element modeling, incident angle, particle image velocimetry, ultrasound thrombolysis 5728