| Structured light enables biomimetic swimming and versatile locomotion of photo-responsive soft microrobots: Microorganisms move in challenging environments by periodic changes in body shape. In contrast, current artificial microrobots cannot actively deform, exhibiting at best passive bending under external fields. Here, by taking advantage of the wireless, scalable and spatiotemporally selective capabilities that light allows, we show that soft microrobots consisting of photoactive liquid-crystal elastomers can be driven by structured monochromatic light to perform sophisticated biomimetic motions. We realize continuum yet selectively addressable artificial microswimmers that generate travelling-wave motions to self-propel without external forces or torques, as well as microrobots capable of versatile locomotion behaviours on demand. Both theoretical predictions and experimental results confirm that multiple gaits, mimicking either symplectic or antiplectic metachrony of ciliate protozoa, can be achieved with single microswimmers. The principle of using structured light can be extended to other applications that require microscale actuation with sophisticated spatiotemporal coordination for advanced microrobotic technologies. | |
Reciprocal Micro-swimmers in Biological Fluids
| Winner of the Micro-robotic Design Challenge in Hamlyn Symposium on Medical Robotics, 23 June 2015, London, UK Authors: T. Qiu, A. Mark, D. Walker, A. Posada, and P. Fischer, Max Planck Institute for Intelligent Systems, Germany. | |
Helical Micro and Nanopropellers for Biological Environments
| Micro-robotic Design Challenge in Hamlyn Symposium on Medical Robotics, 23 June 2015, London, UK Authors: D. Walker, T. Qiu, A. Mark, , A. Posada, and P. Fischer, Max Planck Institute for Intelligent Systems, Germany. | |
| Process illustrated in this video: Tian Qiu, Tung-Chun Lee, Andrew G. Mark, Konstantin I. Morozov, Raphael Münster, Otto Mierka, Stefan Turek, Alexander M. Leshansky, and Peer Fischer. Experimental work was conducted: Prof. Peer Fischer Tian Qiu, Dr. Tung-Chun Lee, Dr. Andrew Mark Max Planck Institute for Intelligent Systems Stuttgart, Germany. In collaboration with: Prof. A. M. Leshansky & Dr. K. I. Morozov Faculty of Chemical Engineering, Technion-Israel Institute of Technology, Haifa, Israel. Prof. S. Turek, R. Münster & Dr. O. Mierka Institute of Applied Mathematics (LS III), TU Dortmund, Dortmund, Germany. | |
Fabrication of Designer Nanostructures
| Here we show how to fabricate precise nanostructures using Glancing Deposition technique (GLAD) by preparing patterned substrates, adjusting deposition angles, and rotating substrates during deposition. We employ materials like metals and oxides. By controlling deposition rates and thicknesses we achieve desired dimensions. Examples of designed particles are helices, janus particles and multimaterial films. GLAD offers advantages such as atomic-level control, low-temperature deposition, scalability, and minimal waste, enabling different applications. | |
| Here we show how we study our nanopropellers in magnetic fields. We aim to can precisely deliver genetic material to cells and navigate complex biological environments, paving the way for targeted gene and drug delivery in minimally invasive medical procedures | |
Akustische Hologramme für "Fast Forward Science 2017"
| Holographic techniques are fundamental to applications such as volumetric displays1, high density data storage and tweezing that require spatial control of intricate optical2 or acoustic fields3,4 within a 3D volume. The basis of holography is spatial storage of the phase and/or amplitude profile of the desired wavefront5,6 in a manner that allows that wavefront to be reconstructed by interference when the hologram is illuminated with a suitable coherent source. Modern computer generated holography7 skips the process of recording a hologram from a physical scene, and instead calculates the required phase profile before rendering it for reconstruction. In ultrasound applications, the phase profile is typically generated by discrete and independently driven ultrasound sources3,4,8-12, whose small number limits the complexity or degrees of freedom that can be attained in the wavefront. Here we introduce monolithic acoustic holograms, which can reconstruct diffraction-limited acoustic pressure fields and thus truly arbitrary ultrasound beams. We use rapid fabrication to craft the holograms and achieve two orders of magnitude higher degrees of freedom than commercial phased array sources. The technique is inexpensive, appropriate for both transmission and reflection elements, and scales well to higher information content, larger aperture size, and higher power. The complex 3D pressure and phase distributions produced by these acoustic holograms allow us to demonstrate new approaches to controlled ultrasonic manipulation of both solids in water, and liquids and solids in air. We expect that acoustic holograms will enable new capabilities in beam-steering and the contactless transfer of power, improve medical imaging, and drive new applications of ultrasound. Teilnahme am Wettbewerb Fast Forward Science http://www.fastforwardscience.de | |
| Holographic techniques are fundamental to applications such as volumetric displays1, high density data storage and tweezing that require spatial control of intricate optical2 or acoustic fields3,4 within a 3D volume. The basis of holography is spatial storage of the phase and/or amplitude profile of the desired wavefront5,6 in a manner that allows that wavefront to be reconstructed by interference when the hologram is illuminated with a suitable coherent source. Modern computer generated holography7 skips the process of recording a hologram from a physical scene, and instead calculates the required phase profile before rendering it for reconstruction. In ultrasound applications, the phase profile is typically generated by discrete and independently driven ultrasound sources3,4,8-12, whose small number limits the complexity or degrees of freedom that can be attained in the wavefront. Here we introduce monolithic acoustic holograms, which can reconstruct diffraction-limited acoustic pressure fields and thus truly arbitrary ultrasound beams. We use rapid fabrication to craft the holograms and achieve two orders of magnitude higher degrees of freedom than commercial phased array sources. The technique is inexpensive, appropriate for both transmission and reflection elements, and scales well to higher information content, larger aperture size, and higher power. The complex 3D pressure and phase distributions produced by these acoustic holograms allow us to demonstrate new approaches to controlled ultrasonic manipulation of both solids in water, and liquids and solids in air. We expect that acoustic holograms will enable new capabilities in beam-steering and the contactless transfer of power, improve medical imaging, and drive new applications of ultrasound. | |
