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Department Talks

Soft Aerial Robotics for Infrastructure Manufacturing

  • 26 September 2019 • 14:00 —15:00
  • Mirko Kovac
  • 2R04

Future cities and infrastructure systems will evolve into complex conglomerates where autonomous aerial, aquatic and ground-based robots will coexist with people and cooperate in symbiosis. To create this human-robot ecosystem, robots will need to respond more flexibly, robustly and efficiently than they do today. They will need to be designed with the ability to move across terrain boundaries and physically interact with infrastructure elements to perform sensing and intervention tasks. Taking inspiration from nature, aerial robotic systems can integrate multi-functional morphology, new materials, energy-efficient locomotion principles and advanced perception abilities that will allow them to successfully operate and cooperate in complex and dynamic environments. This talk will describe the scientific fundamentals, design principles and technologies for the development of biologically inspired flying robots with adaptive morphology that can perform monitoring and manufacturing tasks for future infrastructure and building systems. Examples will include flying robots with perching capabilities and origami-based landing systems, drones for aerial construction and repair, and combustion-based jet thrusters for aerial-aquatic vehicles.

Organizers: Metin Sitti

  • Peter Blümler
  • MPI-IS Stuttgart, Heisenbergstr. 3, room 2P04

A new concept of using permanent magnet systems for guiding superparamagnetic nano-particles (SPP) on arbitrary trajectories over a large volume is presented. The same instrument can also be used for magnetic resonance imaging (MRI) using the inherent contrast of the SPP [1]. The basic idea is to use one magnet system, which provides a strong, homogeneous, dipolar magnetic field to magnetize and orient the particles, and a second constantly graded, quadrupolar field, superimposed on the first, to generate a force on the oriented particles. As a result, particles are guided with constant force and in a single direction over the entire volume. Prototypes of various sizes were constructed to demonstrate the principle in two dimensions on several nanoparticles, which were moved along a rough square by manual adjustment of the force angle [1]. Surprisingly even SPP with sizes < 100 nm could be moved with speeds exceeding 10 mm/s due to reversible agglomeration, for which a first hydrodynamic model is presented. Furthermore, a more advanced system with two quadrupoles is presented which allows canceling the force, hence stopping the SPP and moving them around sharp edges. Additionally, this system also allows for MRI and some first experiments are presented. Recently this concept was combined with liquid crystalline elastomers with incorporated SPP to create “micro-robots” whose coarse maneuvers are performed by a MagGuider-system while there microscopic actuation is controlled either by light or temperature [2]. 1. O. Baun, PB, JMMM 439 (2017) 294-304. doi: 10.1016/j.jmmm.2017.05.001 2. D. Ditter, PB et al. Adv. Functional Mater. 1902454 (2019) doi: 10.1002/adfm.201902454

Organizers: Metin Sitti

An introduction to bladder cancer & challenges for translational research

  • 22 July 2019 • 10:30 AM—22 April 2019 • 11:30 AM
  • Richard T Bryan
  • 2P4

  • Joseph B. Tracy
  • MPI-IS Stuttgart, Room 2P04

Magnetic fields and light can be used to assemble, manipulate, and heat nanoparticles (NPs) and to remotely actuate polymer composites. Simple soft robots will be presented, where incorporation of magnetic and plasmonic NPs makes them responsive to magnetic fields and light. Application of magnetic fields to dispersions of magnetic NPs drives their assembly into chains. Dipolar coupling within the chains is a source of magnetic anisotropy, and chains of magnetic NPs embedded in a polymer matrix can be used to program the response of soft robots, while still using simple architectures. Wavelength-selective photothermal triggering of shape recovery in shape memory polymers with embedded Au nanospheres and nanorods can be used to remotely drive sequential processes. Combining magnetic actuation and photothermal heating enables remote configuration, locking, unlocking, and reconfiguration of soft robots, thus increasing their capabilities. Composite and multifunctional NPs are of interest for expanding the properties and applications of NPs. Silica shells are desirable for facilitating functionalization with silanes and enhancing the stability of NPs. Methods for depositing thin silica shells with controlled morphologies onto Au nanorods and CdSe/CdS core/shell quantum dot nanorods will be presented. Silica deposition can also be accompanied by etching and breakage of the core NPs. Assembly of Fe3O4 NPs onto silica-overcoated Au nanorods allows for magnetic manipulation, while retaining the surface plasmon resonance.

Organizers: Metin Sitti

  • Prof. Shu Yang
  • 2P04

Geometry is concerned with the properties of configurations of points, lines, and circles, while topology is concerned with space, dimension, and transformation. Geometry is also materials independent and scale invariant. By introducing holes and cuts in 2D sheets, we demonstrate dramatic shape change and super-conformability via expanding or collapsing of the hole arrays without deforming individual lattice units. When choosing the cuts and geometry correctly, we show folding into the third dimension, known as kirigami. The kirigami structures can be rendered pluripotent, that is changing into different 3D structures from the same 2D sheet. We explore their potential applications in energy efficient building facade, super-stretchable and shape conformable energy storage devices and medical devices, as well as bioinspired robotics. Programmable shape-shifting materials can take different physical forms to achieve multifunctionality in a dynamic and controllable manner. Through designs of geometric surface patterns, e.g. microchannels, we program the orientational elasticity in liquid crystal elastomers (LCEs), to direct folding of the 2D sheets into 3D shapes, which can be triggered by heat, light, and electric field. Taking this knowledge of guided inhomogeneous local deformations in LCEs, we then tackle the inverse problem – pre-programming geometry on a flat sheet to take an arbitrary desired 3D shape. Lastly, I will show the prospective of taking geometry to create smart fabrics and tendon-like filaments for soft robotic applications.

  • Jérôme Casas
  • 2P04

Insect chemical ecology is a mature, long standing field, with its own journal. By contrast, insect physical ecology is much less studied and the worked scattered. Using work done in my group, I will highlight locomotion, both in granular materials like sand and at the water surface as well as sensing, in particular olfaction and flow sensing. The bio-inspired implementations in MEMS technologies will be the closing chapter.

Organizers: Metin Sitti

Reprogramming Microbial Cells With An Engineering Language

  • 21 March 2019 • 13:30—14:30
  • Sangram Bagh
  • 2P04

The molecular connectivity between genes and proteins inside a cell shows a good degree of resemblance with complex electrical circuits. This inspires the possibility of engineering a cell similar to an engineering device by plugging in genetic logic circuits. This approach, which is loosely defined as synthetic biology is an emerging field of bioengineering, where scientist use electrical and computer engineering principle to re-program cellular functions with a potential to solve next generation challenges in medicine, materials, energy, and space travel. In this talk, we discuss our efforts to create artificial and complex chemical signal processing systems using genetic logic circuits and its applications in building a technology platform for microbial robotics. We further discuss our systems biology effort to understand the effect of microgravity on human and bacterial cells during space travel.

Organizers: Metin Sitti

  • Ingmar H. Riedel-Kruse
  • Max-Planck-Institute for Intelligent Systems, Heisenbergstraße 3, Stuttgart, Room 2P4

I will share my vision that microbiological systems should be as programmable, interactive, accessible, constructible, and useful as our personal electronic devices. Natural multi-cellular organisms and symbiotic systems achieve complex tasks through division of labor among cells. Such systems transcend current electronics and robotics in many ways, e.g., they synthesize chemicals, generate active physical forms, and self-replicate. Harnessing these features promises significant impact for manufacturing (bioelectronics / smart materials /swarm robotics), health (tissue engineering), chemistry (pathway modularization), ecology (bioremediation), biodesign (art), and more. My lab takes a synergistic bottom-up / top-down approach to achieve such transformative applications: (1) We utilize synthetic biology and biophysics approaches to engineer and understand multi-cell bacterial assemblies. We developed the first synthetic cell-cell adhesion toolbox [1] and optogenetic cell-surface adhesion toolbox (‘Biofilm Lithography’) [2]. Integration with standard synthetic biology components (e.g., for signaling, differentiation, logic) now enables a new intelligent materials paradigm that rests on versatile, modular, and composable smart particles (i.e., cells). (2) We pioneered ‘Interactive Biotechnology’ that enables humans to directly interact with living multi-cell assemblies in real-time. I will provide the rational for this interactivity, demonstrate multiple applications using phototactic Euglena cells (e.g., tangible museum exhibits [3], biology cloud experimentation labs [4], biotic video games [5]), and show how this technology aided the discovery of new microswimmer phototaxis control strategies [6]. Finally, I discuss architecture and swarm programming languages for future bio-electronic devices (i.e., ‘Biotic Processing Units’ – BPUs) [7,8]. REFs: [1] Glass, Cell ’18; [2] Jin, PNAS ’18; [3] Lee, CHI ACM ’15; [4] Hossain, Nature Biotech ‘16; [5] Cira, PLoS Biology ‘15; [6] Tsang, Nature Physics ’18; [7] Lam LOC ‘17; [8] Washington, PNAS ‘19.

Magnetically Guided Multiscale Robots and Soft-robotic Grippers

  • 11 December 2018 • 11:00—12:00
  • Dr. František Mach
  • Stuttgart 2P4

The state-of-the-art robotic systems adopting magnetically actuated ferromagnetic bodies or even whole miniature robots have recently become a fast advancing technological field, especially at the nano and microscale. The mesoscale and above all multiscale magnetically guided robotic systems appear to be the advanced field of study, where it is difficult to reflect different forces, precision and also energy demands. The major goal of our talk is to discuss the challenges in the field of magnetically guided mesoscale and multiscale actuation, followed by the results of our research in the field of magnetic positioning systems and the magnetic soft-robotic grippers.

Organizers: Metin Sitti

  • Prof. Holger Stark
  • Stuttgart 2P4

Active motion of biological and artificial microswimmers is relevant in the real world, in microfluidics, and biological applications but also poses fundamental questions in non-equi- librium statistical physics. Mechanisms of single microswimmers either designed by nature or in the lab need to be understood and a detailed modeling of microorganisms helps to explore their complex cell design and their behavior. It also motivates biomimetic approaches. The emergent collective motion of microswimmers generates appealing dynamic patterns as a consequence of the non-equilibrium.

Organizers: Metin Sitti Zoey Davidson