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409 results (View BibTeX file of all listed publications)

2018

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Learning 3D Shape Completion under Weak Supervision

Stutz, D., Geiger, A.

Arxiv, May 2018 (article)

Abstract
We address the problem of 3D shape completion from sparse and noisy point clouds, a fundamental problem in computer vision and robotics. Recent approaches are either data-driven or learning-based: Data-driven approaches rely on a shape model whose parameters are optimized to fit the observations; Learning-based approaches, in contrast, avoid the expensive optimization step by learning to directly predict complete shapes from incomplete observations in a fully-supervised setting. However, full supervision is often not available in practice. In this work, we propose a weakly-supervised learning-based approach to 3D shape completion which neither requires slow optimization nor direct supervision. While we also learn a shape prior on synthetic data, we amortize, i.e., learn, maximum likelihood fitting using deep neural networks resulting in efficient shape completion without sacrificing accuracy. On synthetic benchmarks based on ShapeNet and ModelNet as well as on real robotics data from KITTI and Kinect, we demonstrate that the proposed amortized maximum likelihood approach is able to compete with fully supervised baselines and outperforms data-driven approaches, while requiring less supervision and being significantly faster.

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PDF Project Page Project Page [BibTex]

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Nonlinear decoding of a complex movie from the mammalian retina

Botella-Soler, V., Deny, S., Martius, G., Marre, O., Tkačik, G.

PLOS Computational Biology, 14(5):1-27, Public Library of Science, May 2018 (article)

Abstract
Author summary Neurons in the retina transform patterns of incoming light into sequences of neural spikes. We recorded from ∼100 neurons in the rat retina while it was stimulated with a complex movie. Using machine learning regression methods, we fit decoders to reconstruct the movie shown from the retinal output. We demonstrated that retinal code can only be read out with a low error if decoders make use of correlations between successive spikes emitted by individual neurons. These correlations can be used to ignore spontaneous spiking that would, otherwise, cause even the best linear decoders to “hallucinate” nonexistent stimuli. This work represents the first high resolution single-trial full movie reconstruction and suggests a new paradigm for separating spontaneous from stimulus-driven neural activity.

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DOI [BibTex]

al Botella-Soler, V., Deny, S., Martius, G., Marre, O., Tkačik, G. Nonlinear decoding of a complex movie from the mammalian retina PLOS Computational Biology, 14(5):1-27, Public Library of Science, May 2018 (article)

DOI [BibTex]

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Graphene-silver hybrid devices for sensitive photodetection in the ultraviolet

Paria, D., Jeong, H. H., Vadakkumbatt, V., Deshpande, P., Fischer, P., Ghosh, A., Ghosh, A.

Nanoscale, 10, pages: 7685-7693, April 2018 (article)

Abstract
The weak light-matter interaction in graphene can be enhanced with a number of strategies, among which sensitization with plasmonic nanostructures is particularly attractive. This has resulted in the development of graphene-plasmonic hybrid systems with strongly enhanced photodetection efficiencies in the visible and the IR, but none in the UV. Here, we describe a silver nanoparticle-graphene stacked optoelectronic device that shows strong enhancement of its photoresponse across the entire UV spectrum. The device fabrication strategy is scalable and modular. Self-assembly techniques are combined with physical shadow growth techniques to fabricate a regular large-area array of 50 nm silver nanoparticles onto which CVD graphene is transferred. The presence of the silver nanoparticles resulted in a plasmonically enhanced photoresponse as high as 3.2 A W-1 in the wavelength range from 330 nm to 450 nm. At lower wavelengths, close to the Van Hove singularity of the density of states in graphene, we measured an even higher responsivity of 14.5 A W-1 at 280 nm, which corresponds to a more than 10 000-fold enhancement over the photoresponse of native graphene.

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link (url) DOI [BibTex]

pf Paria, D., Jeong, H. H., Vadakkumbatt, V., Deshpande, P., Fischer, P., Ghosh, A., Ghosh, A. Graphene-silver hybrid devices for sensitive photodetection in the ultraviolet Nanoscale, 10, pages: 7685-7693, April 2018 (article)

link (url) DOI [BibTex]

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Nanoparticles on the move for medicine

Fischer, P.

Physics World Focus on Nanotechnology, pages: 26028, (Editors: Margaret Harris), IOP Publishing Ltd and individual contributors, April 2018 (article)

Abstract
Peer Fischer outlines the prospects for creating “nanoswimmers” that can be steered through the body to deliver drugs directly to their targets Molecules don’t move very fast on their own. If they had to rely solely on diffusion – a slow and inefficient process linked to the Brownian motion of small particles and molecules in solution – then a protein mole­cule, for instance, would take around three weeks to travel a single centimetre down a nerve fibre. This is why active transport mechanisms exist in cells and in the human body: without them, all the processes of life would happen at a pace that would make snails look speedy.

pf

link (url) [BibTex]

pf Fischer, P. Nanoparticles on the move for medicine Physics World Focus on Nanotechnology, pages: 26028, (Editors: Margaret Harris), IOP Publishing Ltd and individual contributors, April 2018 (article)

link (url) [BibTex]

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Mixture of Attractors: A Novel Movement Primitive Representation for Learning Motor Skills From Demonstrations

Manschitz, S., Gienger, M., Kober, J., Peters, J.

IEEE Robotics and Automation Letters, 3(2):926-933, April 2018 (article)

ei

DOI Project Page [BibTex]

ei Manschitz, S., Gienger, M., Kober, J., Peters, J. Mixture of Attractors: A Novel Movement Primitive Representation for Learning Motor Skills From Demonstrations IEEE Robotics and Automation Letters, 3(2):926-933, April 2018 (article)

DOI Project Page [BibTex]

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Soft erythrocyte-based bacterial microswimmers for cargo delivery

Alapan, Y., Yasa, O., Schauer, O., Giltinan, J., Tabak, A. F., Sourjik, V., Sitti, M.

Science Robotics, 3(17):eaar4423, Science Robotics, April 2018 (article)

Abstract
Bacteria-propelled biohybrid microswimmers have recently shown to be able to actively transport and deliver cargos encapsulated into their synthetic constructs to specific regions locally. However, usage of synthetic materials as cargo carriers can result in inferior performance in load-carrying efficiency, biocompatibility, and biodegradability, impeding clinical translation of biohybrid microswimmers. Here, we report construction and external guidance of bacteria-driven microswimmers using red blood cells (RBCs; erythrocytes) as autologous cargo carriers for active and guided drug delivery. Multifunctional biohybrid microswimmers were fabricated by attachment of RBCs [loaded with anticancer doxorubicin drug molecules and superparamagnetic iron oxide nanoparticles (SPIONs)] to bioengineered motile bacteria, Escherichia coli MG1655, via biotin-avidin-biotin binding complex. Autonomous and on-board propulsion of biohybrid microswimmers was provided by bacteria, and their external magnetic guidance was enabled by SPIONs loaded into the RBCs. Furthermore, bacteria-driven RBC microswimmers displayed preserved deformability and attachment stability even after squeezing in microchannels smaller than their sizes, as in the case of bare RBCs. In addition, an on-demand light-activated hyperthermia termination switch was engineered for RBC microswimmers to control bacteria population after operations. RBCs, as biological and autologous cargo carriers in the biohybrid microswimmers, offer notable advantages in stability, deformability, biocompatibility, and biodegradability over synthetic cargo-carrier materials. The biohybrid microswimmer design presented here transforms RBCs from passive cargo carriers into active and guidable cargo carriers toward targeted drug and other cargo delivery applications in medicine.

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link (url) DOI Project Page Project Page [BibTex]

pi Alapan, Y., Yasa, O., Schauer, O., Giltinan, J., Tabak, A. F., Sourjik, V., Sitti, M. Soft erythrocyte-based bacterial microswimmers for cargo delivery Science Robotics, 3(17):eaar4423, Science Robotics, April 2018 (article)

link (url) DOI Project Page Project Page [BibTex]

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Automatically Rating Trainee Skill at a Pediatric Laparoscopic Suturing Task

Oquendo, Y. A., Riddle, E. W., Hiller, D., Blinman, T. A., Kuchenbecker, K. J.

Surgical Endoscopy, 32(4):1840-1857, April 2018 (article)

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DOI [BibTex]

hi Oquendo, Y. A., Riddle, E. W., Hiller, D., Blinman, T. A., Kuchenbecker, K. J. Automatically Rating Trainee Skill at a Pediatric Laparoscopic Suturing Task Surgical Endoscopy, 32(4):1840-1857, April 2018 (article)

DOI [BibTex]

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Miniature soft robots – road to the clinic

Sitti, M.

Nature Reviews Materials, April 2018 (article)

Abstract
Soft small robots offer the opportunity to non-invasively access human tissue to perform medical operations and deliver drugs; however, challenges in materials design, biocompatibility and function control remain to be overcome for soft robots to reach the clinic.

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link (url) DOI [BibTex]

pi Sitti, M. Miniature soft robots – road to the clinic Nature Reviews Materials, April 2018 (article)

link (url) DOI [BibTex]

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Probabilistic movement primitives under unknown system dynamics

Paraschos, A., Rueckert, E., Peters, J., Neumann, G.

Advanced Robotics, 32(6):297-310, April 2018 (article)

ei

DOI Project Page [BibTex]

ei Paraschos, A., Rueckert, E., Peters, J., Neumann, G. Probabilistic movement primitives under unknown system dynamics Advanced Robotics, 32(6):297-310, April 2018 (article)

DOI Project Page [BibTex]

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Wrinkling Instability and Adhesion of a Highly Bendable Gallium Oxide Nanofilm Encapsulating a Liquid-Gallium Droplet

Yunusa, M., Amador, G. J., Drotlef, D., Sitti, M.

Nano Letters, 18(4):2498-2504, March 2018 (article)

Abstract
The wrinkling and interfacial adhesion mechanics of a gallium-oxide nanofilm encapsulating a liquid-gallium droplet are presented. The native oxide nanofilm provides mechanical stability by preventing the flow of the liquid metal. We show how a crumpled oxide skin a few nanometers thick behaves akin to a highly bendable elastic nanofilm under ambient conditions. Upon compression, a wrinkling instability emerges at the contact interface to relieve the applied stress. As the load is further increased, radial wrinkles evolve, and, eventually, the oxide nanofilm ruptures. The observed wrinkling closely resembles the instability experienced by nanofilms under axisymmetric loading, thus providing further insights into the behaviors of elastic nanofilms. Moreover, the mechanical attributes of the oxide skin enable high surface conformation by exhibiting liquid-like behavior. We measured an adhesion energy of 0.238 ± 0.008 J m–2 between a liquid-gallium droplet and smooth flat glass, which is close to the measurements of thin-sheet nanomaterials such as graphene on silicon dioxide.

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link (url) DOI [BibTex]

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Magnetic-Visual Sensor Fusion-based Dense 3D Reconstruction and Localization for Endoscopic Capsule Robots

Turan, M., Almalioglu, Y., Ornek, E. P., Araujo, H., Yanik, M. F., Sitti, M.

ArXiv e-prints, March 2018 (article)

Abstract
Reliable and real-time 3D reconstruction and localization functionality is a crucial prerequisite for the navigation of actively controlled capsule endoscopic robots as an emerging, minimally invasive diagnostic and therapeutic technology for use in the gastrointestinal (GI) tract. In this study, we propose a fully dense, non-rigidly deformable, strictly real-time, intraoperative map fusion approach for actively controlled endoscopic capsule robot applications which combines magnetic and vision-based localization, with non-rigid deformations based frame-to-model map fusion. The performance of the proposed method is demonstrated using four different ex-vivo porcine stomach models. Across different trajectories of varying speed and complexity, and four different endoscopic cameras, the root mean square surface reconstruction errors 1.58 to 2.17 cm.

pi

link (url) [BibTex]

pi Turan, M., Almalioglu, Y., Ornek, E. P., Araujo, H., Yanik, M. F., Sitti, M. Magnetic-Visual Sensor Fusion-based Dense 3D Reconstruction and Localization for Endoscopic Capsule Robots ArXiv e-prints, March 2018 (article)

link (url) [BibTex]

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Unsupervised Odometry and Depth Learning for Endoscopic Capsule Robots

Turan, M., Ornek, E. P., Ibrahimli, N., Giracoglu, C., Almalioglu, Y., Yanik, M. F., Sitti, M.

ArXiv e-prints, March 2018 (article)

Abstract
In the last decade, many medical companies and research groups have tried to convert passive capsule endoscopes as an emerging and minimally invasive diagnostic technology into actively steerable endoscopic capsule robots which will provide more intuitive disease detection, targeted drug delivery and biopsy-like operations in the gastrointestinal(GI) tract. In this study, we introduce a fully unsupervised, real-time odometry and depth learner for monocular endoscopic capsule robots. We establish the supervision by warping view sequences and assigning the re-projection minimization to the loss function, which we adopt in multi-view pose estimation and single-view depth estimation network. Detailed quantitative and qualitative analyses of the proposed framework performed on non-rigidly deformable ex-vivo porcine stomach datasets proves the effectiveness of the method in terms of motion estimation and depth recovery.

pi

link (url) [BibTex]

pi Turan, M., Ornek, E. P., Ibrahimli, N., Giracoglu, C., Almalioglu, Y., Yanik, M. F., Sitti, M. Unsupervised Odometry and Depth Learning for Endoscopic Capsule Robots ArXiv e-prints, March 2018 (article)

link (url) [BibTex]

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Self‐Folded Hydrogel Tubes for Implantable Muscular Tissue Scaffolds

Vannozzi, L., Yasa, I. C., Ceylan, H., Menciassi, A., Ricotti, L., Sitti, M.

Macromolecular Bioscience, (0), March 2018 (article)

Abstract
Abstract Programming materials with tunable physical and chemical interactions among its components pave the way of generating 3D functional active microsystems with various potential applications in tissue engineering, drug delivery, and soft robotics. Here, the development of a recapitulated fascicle‐like implantable muscle construct by programmed self‐folding of poly(ethylene glycol) diacrylate hydrogels is reported. The system comprises two stacked layers, each with differential swelling degrees, stiffnesses, and thicknesses in 2D, which folds into a 3D tube together. Inside the tubes, muscle cell adhesion and their spatial alignment are controlled. Both skeletal and cardiac muscle cells also exhibit high viability, and cardiac myocytes preserve their contractile function over the course of 7 d. Integration of biological cells with smart, shape‐changing materials could give rise to the development of new cellular constructs for hierarchical tissue assembly, drug testing platforms, and biohybrid actuators that can perform sophisticated tasks.

pi

link (url) DOI [BibTex]

pi Vannozzi, L., Yasa, I. C., Ceylan, H., Menciassi, A., Ricotti, L., Sitti, M. Self‐Folded Hydrogel Tubes for Implantable Muscular Tissue Scaffolds Macromolecular Bioscience, (0), March 2018 (article)

link (url) DOI [BibTex]

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Redox metals homeostasis in multiple sclerosis and amyotrophic lateral sclerosis: a review

Sheykhansari, S., Kozielski, K., Bill, J., Sitti, M., Gemmati, D., Zamboni, P., Singh, A. V.

Cell Death \& Disease, 9(3):348, March 2018 (article)

Abstract
The effect of redox metals such as iron and copper on multiple sclerosis and amyotrophic lateral sclerosis has been intensively studied. However, the origin of these disorders remains uncertain. This review article critically describes the physiology of redox metals that produce oxidative stress, which in turn leads to cascades of immunomodulatory alteration of neurons in multiple sclerosis and amyotrophic lateral sclerosis. Iron and copper overload has been well established in motor neurons of these diseases' lesions. On the other hand, the role of other metals like cadmium participating indirectly in the redox cascade of neurobiological mechanism is less studied. In the second part of this review, we focus on this less conspicuous correlation between cadmium as an inactive-redox metal and multiple sclerosis and amyotrophic lateral sclerosis, providing novel treatment modalities and approaches as future prospects.

pi

link (url) DOI [BibTex]

pi Sheykhansari, S., Kozielski, K., Bill, J., Sitti, M., Gemmati, D., Zamboni, P., Singh, A. V. Redox metals homeostasis in multiple sclerosis and amyotrophic lateral sclerosis: a review Cell Death \& Disease, 9(3):348, March 2018 (article)

link (url) DOI [BibTex]

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Cancer cells biomineralize ionic gold into nanoparticles-microplates via secreting defense proteins with specific gold-binding peptides

Singh, A. V., Jahnke, T., Kishore, V., Park, B., Batuwangala, M., Bill, J., Sitti, M.

Acta Biomaterialia, March 2018 (article)

Abstract
Cancer cells have the capacity to synthesize nanoparticles (NPs). The detailed mechanism of this process is not very well documented. We report the mechanism of biomineralization of aqueous gold chloride into NPs and microplates in the breast-cancer cell line MCF7. Spherical gold NPs are synthesized in these cells in the presence of serum in the culture media by the reduction of HAuCl4. In the absence of serum, the cells exhibit gold microplate formation through seed-mediate growth albeit slower reduction. The structural characteristics of the two types of NPs under different media conditions were confirmed using scanning electron microscopy (SEM); crystallinity and metallic properties were assessed with transmission electron microscopy (TEM) and x-ray photoelectron spectroscopy (XPS). Gold-reducing proteins, related to cell stress initiate the biomineralization of HAuCl4 in cells (under serum free conditions) as confirmed by infrared (IR) spectroscopy. MCF7 cells undergo irreversible replicative senescence when exposed to a high concentration of ionic gold and conversely remain in a dormant reversible quiescent state when exposed to a low gold concentration. The latter cellular state was achievable in the presence of the rho/ROCK inhibitor Y-27632. Proteomic analysis revealed consistent expression of specific proteins under serum and serum-free conditions. A high-throughput proteomic approach to screen gold-reducing proteins and peptide sequences was utilized and validated by quartz crystal microbalance with dissipation (QCM-D). Statement of significance Cancer cells are known to synthesize gold nanoparticles and microstructures, which are promising for bioimaging and other therapeutic applications. However, the detailed mechanism of such biomineralization process is not well understood yet. Herein, we demonstrate that cancer cells exposed to gold ions (grown in serum/serum-free conditions) secrete shock and stress-related proteins with specific gold-binding/reducing polypeptides. Cells undergo reversible senescence and can recover normal physiology when treated with the senescence inhibitor depending on culture condition. The use of mammalian cells as microincubators for synthesis of such particles could have potential influence on their uptake and biocompatibility. This study has important implications for in-situ reduction of ionic gold to anisotropic micro-nanostructures that could be used in-vivo clinical applications and tumor photothermal therapy.

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link (url) DOI [BibTex]

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Arm-Worn Tactile Displays

Kuchenbecker, K. J.

Cross-Cutting Challenge Interactive Discussion presented at the IEEE Haptics Symposium, San Francisco, USA, March 2018 (misc)

Abstract
Fingertips and hands captivate the attention of most haptic interface designers, but humans can feel touch stimuli across the entire body surface. Trying to create devices that both can be worn and can deliver good haptic sensations raises challenges that rarely arise in other contexts. Most notably, tactile cues such as vibration, tapping, and squeezing are far simpler to implement in wearable systems than kinesthetic haptic feedback. This interactive discussion will present a variety of relevant projects to which I have contributed, attempting to pull out common themes and ideas for the future.

hi

[BibTex]

hi Kuchenbecker, K. J. Arm-Worn Tactile Displays Cross-Cutting Challenge Interactive Discussion presented at the IEEE Haptics Symposium, San Francisco, USA, March 2018 (misc)

[BibTex]

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Haptipedia: An Expert-Sourced Interactive Device Visualization for Haptic Designers

Seifi, H., MacLean, K. E., Kuchenbecker, K. J., Park, G.

Work-in-progress paper (3 pages) presented at the IEEE Haptics Symposium, San Francisco, USA, March 2018 (misc)

Abstract
Much of three decades of haptic device invention is effectively lost to today’s designers: dispersion across time, region, and discipline imposes an incalculable drag on innovation in this field. Our goal is to make historical haptic invention accessible through interactive navigation of a comprehensive library – a Haptipedia – of devices that have been annotated with designer-relevant metadata. To build this open resource, we will systematically mine the literature and engage the haptics community for expert annotation. In a multi-year broad-based initiative, we will empirically derive salient attributes of haptic devices, design an interactive visualization tool where device creators and repurposers can efficiently explore and search Haptipedia, and establish methods and tools to manually and algorithmically collect data from the haptics literature and our community of experts. This paper outlines progress in compiling an initial corpus of grounded force-feedback devices and their attributes, and it presents a concept sketch of the interface we envision.

hi

Project Page [BibTex]

hi Seifi, H., MacLean, K. E., Kuchenbecker, K. J., Park, G. Haptipedia: An Expert-Sourced Interactive Device Visualization for Haptic Designers Work-in-progress paper (3 pages) presented at the IEEE Haptics Symposium, San Francisco, USA, March 2018 (misc)

Project Page [BibTex]

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An Algorithmic Perspective on Imitation Learning

Osa, T., Pajarinen, J., Neumann, G., Bagnell, J., Abbeel, P., Peters, J.

Foundations and Trends in Robotics, 7(1-2):1-179, March 2018 (article)

ei

DOI Project Page [BibTex]

ei Osa, T., Pajarinen, J., Neumann, G., Bagnell, J., Abbeel, P., Peters, J. An Algorithmic Perspective on Imitation Learning Foundations and Trends in Robotics, 7(1-2):1-179, March 2018 (article)

DOI Project Page [BibTex]

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Assessing body image in anorexia nervosa using biometric self-avatars in virtual reality: Attitudinal components rather than visual body size estimation are distorted

Mölbert, S. C., Thaler, A., Mohler, B. J., Streuber, S., Romero, J., Black, M. J., Zipfel, S., Karnath, H., Giel, K. E.

Psychological Medicine, 48(4):642-653, March 2018 (article)

Abstract
Background: Body image disturbance (BID) is a core symptom of anorexia nervosa (AN), but as yet distinctive features of BID are unknown. The present study aimed at disentangling perceptual and attitudinal components of BID in AN. Methods: We investigated n=24 women with AN and n=24 controls. Based on a 3D body scan, we created realistic virtual 3D bodies (avatars) for each participant that were varied through a range of ±20% of the participants' weights. Avatars were presented in a virtual reality mirror scenario. Using different psychophysical tasks, participants identified and adjusted their actual and their desired body weight. To test for general perceptual biases in estimating body weight, a second experiment investigated perception of weight and shape matched avatars with another identity. Results: Women with AN and controls underestimated their weight, with a trend that women with AN underestimated more. The average desired body of controls had normal weight while the average desired weight of women with AN corresponded to extreme AN (DSM-5). Correlation analyses revealed that desired body weight, but not accuracy of weight estimation, was associated with eating disorder symptoms. In the second experiment, both groups estimated accurately while the most attractive body was similar to Experiment 1. Conclusions: Our results contradict the widespread assumption that patients with AN overestimate their body weight due to visual distortions. Rather, they illustrate that BID might be driven by distorted attitudes with regard to the desired body. Clinical interventions should aim at helping patients with AN to change their desired weight.

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doi pdf DOI Project Page [BibTex]

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Exercising with Baxter: Design and Evaluation of Assistive Social-Physical Human-Robot Interaction

Fitter, N. T., Mohan, M., Kuchenbecker, K. J., Johnson, M. J.

Workshop paper (6 pages) presented at the HRI Workshop on Personal Robots for Exercising and Coaching, Chicago, USA, March 2018 (misc)

Abstract
The worldwide population of older adults is steadily increasing and will soon exceed the capacity of assisted living facilities. Accordingly, we aim to understand whether appropriately designed robots could help older adults stay active and engaged while living at home. We developed eight human-robot exercise games for the Baxter Research Robot with the guidance of experts in game design, therapy, and rehabilitation. After extensive iteration, these games were employed in a user study that tested their viability with 20 younger and 20 older adult users. All participants were willing to enter Baxter’s workspace and physically interact with the robot. User trust and confidence in Baxter increased significantly between pre- and post-experiment assessments, and one individual from the target user population supplied us with abundant positive feedback about her experience. The preliminary results presented in this paper indicate potential for the use of two-armed human-scale robots for social-physical exercise interaction.

hi

link (url) Project Page [BibTex]

hi Fitter, N. T., Mohan, M., Kuchenbecker, K. J., Johnson, M. J. Exercising with Baxter: Design and Evaluation of Assistive Social-Physical Human-Robot Interaction Workshop paper (6 pages) presented at the HRI Workshop on Personal Robots for Exercising and Coaching, Chicago, USA, March 2018 (misc)

link (url) Project Page [BibTex]

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Using Probabilistic Movement Primitives in Robotics

Paraschos, A., Daniel, C., Peters, J., Neumann, G.

Autonomous Robots, 42(3):529-551, March 2018 (article)

ei

DOI Project Page [BibTex]

ei Paraschos, A., Daniel, C., Peters, J., Neumann, G. Using Probabilistic Movement Primitives in Robotics Autonomous Robots, 42(3):529-551, March 2018 (article)

DOI Project Page [BibTex]

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Emotionally Supporting Humans Through Robot Hugs

Block, A. E., Kuchenbecker, K. J.

Workshop paper (2 pages) presented at the HRI Pioneers Workshop, Chicago, USA, March 2018 (misc)

Abstract
Hugs are one of the first forms of contact and affection humans experience. Due to their prevalence and health benefits, we want to enable robots to safely hug humans. This research strives to create and study a high fidelity robotic system that provides emotional support to people through hugs. This paper outlines our previous work evaluating human responses to a prototype’s physical and behavioral characteristics, and then it lays out our ongoing and future work.

hi

link (url) DOI Project Page [BibTex]

hi Block, A. E., Kuchenbecker, K. J. Emotionally Supporting Humans Through Robot Hugs Workshop paper (2 pages) presented at the HRI Pioneers Workshop, Chicago, USA, March 2018 (misc)

link (url) DOI Project Page [BibTex]

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Towards a Statistical Model of Fingertip Contact Deformations from 4D Data

Gueorguiev, D., Tzionas, D., Pacchierotti, C., Black, M. J., Kuchenbecker, K. J.

Work-in-progress paper (3 pages) presented at the IEEE Haptics Symposium, San Francisco, USA, March 2018 (misc)

Abstract
Little is known about the shape and properties of the human finger during haptic interaction even though this knowledge is essential to control wearable finger devices and deliver realistic tactile feedback. This study explores a framework for four-dimensional scanning and modeling of finger-surface interactions, aiming to capture the motion and deformations of the entire finger with high resolution. The results show that when the fingertip is actively pressing a rigid surface, it undergoes lateral expansion of about 0.2 cm and proximal/distal bending of about 30◦, deformations that cannot be captured by imaging of the contact area alone. This project constitutes a first step towards an accurate statistical model of the finger’s behavior during haptic interaction.

hi

link (url) Project Page [BibTex]

hi Gueorguiev, D., Tzionas, D., Pacchierotti, C., Black, M. J., Kuchenbecker, K. J. Towards a Statistical Model of Fingertip Contact Deformations from 4D Data Work-in-progress paper (3 pages) presented at the IEEE Haptics Symposium, San Francisco, USA, March 2018 (misc)

link (url) Project Page [BibTex]

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A kernel-based approach to learning contact distributions for robot manipulation tasks

Kroemer, O., Leischnig, S., Luettgen, S., Peters, J.

Autonomous Robots, 42(3):581-600, March 2018 (article)

ei

DOI Project Page [BibTex]

ei Kroemer, O., Leischnig, S., Luettgen, S., Peters, J. A kernel-based approach to learning contact distributions for robot manipulation tasks Autonomous Robots, 42(3):581-600, March 2018 (article)

DOI Project Page [BibTex]

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Can Humans Infer Haptic Surface Properties from Images?

Burka, A., Kuchenbecker, K. J.

Work-in-progress paper (3 pages) presented at the IEEE Haptics Symposium, San Francisco, USA, March 2018 (misc)

Abstract
Human children typically experience their surroundings both visually and haptically, providing ample opportunities to learn rich cross-sensory associations. To thrive in human environments and interact with the real world, robots also need to build models of these cross-sensory associations; current advances in machine learning should make it possible to infer models from large amounts of data. We previously built a visuo-haptic sensing device, the Proton Pack, and are using it to collect a large database of matched multimodal data from tool-surface interactions. As a benchmark to compare with machine learning performance, we conducted a human subject study (n = 84) on estimating haptic surface properties (here: hardness, roughness, friction, and warmness) from images. Using a 100-surface subset of our database, we showed images to study participants and collected 5635 ratings of the four haptic properties, which we compared with ratings made by the Proton Pack operator and with physical data recorded using motion, force, and vibration sensors. Preliminary results indicate weak correlation between participant and operator ratings, but potential for matching up certain human ratings (particularly hardness and roughness) with features from the literature.

hi

Project Page [BibTex]

hi Burka, A., Kuchenbecker, K. J. Can Humans Infer Haptic Surface Properties from Images? Work-in-progress paper (3 pages) presented at the IEEE Haptics Symposium, San Francisco, USA, March 2018 (misc)

Project Page [BibTex]

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Photogravitactic Microswimmers

Singh, D. P., Uspal, W. E., Popescu, M. N., Wilson, L. G., Fischer, P.

Adv. Func. Mat., 28, pages: 1706660, Febuary 2018 (article)

Abstract
Abstract Phototactic microorganisms are commonly observed to respond to natural sunlight by swimming upward against gravity. This study demonstrates that synthetic photochemically active microswimmers can also swim against gravity. The particles initially sediment and, when illuminated at low light intensities exhibit wall‐bound states of motion near the bottom surface. Upon increasing the intensity of light, the artificial swimmers lift off from the wall and swim against gravity and away from the light source. This motion in the bulk has been further confirmed using holographic microscopy. A theoretical model is presented within the framework of self‐diffusiophoresis, which allows to unequivocally identify the photochemical activity and the phototactic response as key mechanisms in the observed phenomenology. Since the lift‐off threshold intensity depends on the particle size, it can be exploited to selectively address particles with the same density from a polydisperse mixture of active particles and move them in or out of the boundary region. This study provides a simple design strategy to fabricate artificial microswimmers whose two‐ or three‐dimensional swimming behavior can be controlled with light.

pf

link (url) DOI [BibTex]

pf Singh, D. P., Uspal, W. E., Popescu, M. N., Wilson, L. G., Fischer, P. Photogravitactic Microswimmers Adv. Func. Mat., 28, pages: 1706660, Febuary 2018 (article)

link (url) DOI [BibTex]

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Chiral Plasmonic Hydrogen Sensors

Matuschek, M., Singh, D. P., Hyeon-Ho, J., Nesterov, M., Weiss, T., Fischer, P., Neubrech, F., Na Liu, L.

Small, 14(7):1702990, Febuary 2018 (article)

Abstract
In this article, a chiral plasmonic hydrogen‐sensing platform using palladium‐based nanohelices is demonstrated. Such 3D chiral nanostructures fabricated by nanoglancing angle deposition exhibit strong circular dichroism both experimentally and theoretically. The chiroptical properties of the palladium nanohelices are altered upon hydrogen uptake and sensitively depend on the hydrogen concentration. Such properties are well suited for remote and spark‐free hydrogen sensing in the flammable range. Hysteresis is reduced, when an increasing amount of gold is utilized in the palladium‐gold hybrid helices. As a result, the linearity of the circular dichroism in response to hydrogen is significantly improved. The chiral plasmonic sensor scheme is of potential interest for hydrogen‐sensing applications, where good linearity and high sensitivity are required.

pf

link (url) DOI [BibTex]

pf Matuschek, M., Singh, D. P., Hyeon-Ho, J., Nesterov, M., Weiss, T., Fischer, P., Neubrech, F., Na Liu, L. Chiral Plasmonic Hydrogen Sensors Small, 14(7):1702990, Febuary 2018 (article)

link (url) DOI [BibTex]

Thumb xl screenshot 2018 5 9 1802 00475 pdf
Thermocapillary-driven fluid flow within microchannels

Amador, G. J., Tabak, A. F., Ren, Z., Alapan, Y., Yasa, O., Sitti, M.

ArXiv e-prints, Febuary 2018 (article)

Abstract
Surface tension gradients induce Marangoni flow, which may be exploited for fluid transport. At the micrometer scale, these surface-driven flows can be more significant than those driven by pressure. By introducing fluid-fluid interfaces on the walls of microfluidic channels, we use surface tension gradients to drive bulk fluid flows. The gradients are specifically induced through thermal energy, exploiting the temperature dependence of a fluid-fluid interface to generate thermocapillary flow. In this report, we provide the design concept for a biocompatible, thermocapillary microchannel capable of being powered by solar irradiation. Using temperature gradients on the order of degrees Celsius per centimeter, we achieve fluid velocities on the order of millimeters per second. Following experimental observations, fluid dynamic models, and numerical simulation, we find that the fluid velocity is linearly proportional to the provided temperature gradient, enabling full control of the fluid flow within the microchannels.

pi

link (url) Project Page [BibTex]

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Sparse-then-dense alignment-based 3D map reconstruction method for endoscopic capsule robots

Turan, M., Pilavci, Y. Y., Ganiyusufoglu, I., Araujo, H., Konukoglu, E., Sitti, M.

Machine Vision and Applications, 29(2):345-359, Febuary 2018 (article)

Abstract
Despite significant progress achieved in the last decade to convert passive capsule endoscopes to actively controllable robots, robotic capsule endoscopy still has some challenges. In particular, a fully dense three-dimensional (3D) map reconstruction of the explored organ remains an unsolved problem. Such a dense map would help doctors detect the locations and sizes of the diseased areas more reliably, resulting in more accurate diagnoses. In this study, we propose a comprehensive medical 3D reconstruction method for endoscopic capsule robots, which is built in a modular fashion including preprocessing, keyframe selection, sparse-then-dense alignment-based pose estimation, bundle fusion, and shading-based 3D reconstruction. A detailed quantitative analysis is performed using a non-rigid esophagus gastroduodenoscopy simulator, four different endoscopic cameras, a magnetically activated soft capsule robot, a sub-millimeter precise optical motion tracker, and a fine-scale 3D optical scanner, whereas qualitative ex-vivo experiments are performed on a porcine pig stomach. To the best of our knowledge, this study is the first complete endoscopic 3D map reconstruction approach containing all of the necessary functionalities for a therapeutically relevant 3D map reconstruction.

pi

link (url) DOI [BibTex]

pi Turan, M., Pilavci, Y. Y., Ganiyusufoglu, I., Araujo, H., Konukoglu, E., Sitti, M. Sparse-then-dense alignment-based 3D map reconstruction method for endoscopic capsule robots Machine Vision and Applications, 29(2):345-359, Febuary 2018 (article)

link (url) DOI [BibTex]

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Body size estimation of self and others in females varying in BMI

Thaler, A., Geuss, M. N., Mölbert, S. C., Giel, K. E., Streuber, S., Romero, J., Black, M. J., Mohler, B. J.

PLoS ONE, 13(2), Febuary 2018 (article)

Abstract
Previous literature suggests that a disturbed ability to accurately identify own body size may contribute to overweight. Here, we investigated the influence of personal body size, indexed by body mass index (BMI), on body size estimation in a non-clinical population of females varying in BMI. We attempted to disentangle general biases in body size estimates and attitudinal influences by manipulating whether participants believed the body stimuli (personalized avatars with realistic weight variations) represented their own body or that of another person. Our results show that the accuracy of own body size estimation is predicted by personal BMI, such that participants with lower BMI underestimated their body size and participants with higher BMI overestimated their body size. Further, participants with higher BMI were less likely to notice the same percentage of weight gain than participants with lower BMI. Importantly, these results were only apparent when participants were judging a virtual body that was their own identity (Experiment 1), but not when they estimated the size of a body with another identity and the same underlying body shape (Experiment 2a). The different influences of BMI on accuracy of body size estimation and sensitivity to weight change for self and other identity suggests that effects of BMI on visual body size estimation are self-specific and not generalizable to other bodies.

ps

pdf DOI Project Page [BibTex]

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Independent Actuation of Two-Tailed Microrobots

Khalil, I. S. M., Tabak, A. F., Hamed, Y., Tawakol, M., Klingner, A., Gohary, N. E., Mizaikoff, B., Sitti, M.

IEEE Robotics and Automation Letters, 3(3):1703-1710, Febuary 2018 (article)

Abstract
A soft two-tailed microrobot in low Reynolds number fluids does not achieve forward locomotion by identical tails regardless to its wiggling frequency. If the tails are nonidentical, zero forward locomotion is also observed at specific oscillation frequencies (which we refer to as the reversal frequencies), as the propulsive forces imparted to the fluid by each tail are almost equal in magnitude and opposite in direction. We find distinct reversal frequencies for the two-tailed microrobots based on their tail length ratio. At these frequencies, the microrobot achieves negligible net displacement under the influence of a periodic magnetic field. This observation allows us to fabricate groups of microrobots with tail length ratio of 1.24 ± 0.11, 1.48 ± 0.08, and 1.71 ± 0.09. We demonstrate selective actuation of microrobots based on prior characterization of their reversal frequencies. We also implement simultaneous flagellar propulsion of two microrobots and show that they can be controlled to swim along the same direction and opposite to each other using common periodic magnetic fields. In addition, independent motion control of two microrobots is achieved toward two different reference positions with average steady-state error of 110.1 ± 91.8 μm and 146.9 ± 105.9 μm.

pi

link (url) DOI [BibTex]

pi Khalil, I. S. M., Tabak, A. F., Hamed, Y., Tawakol, M., Klingner, A., Gohary, N. E., Mizaikoff, B., Sitti, M. Independent Actuation of Two-Tailed Microrobots IEEE Robotics and Automation Letters, 3(3):1703-1710, Febuary 2018 (article)

link (url) DOI [BibTex]

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Co-Registration – Simultaneous Alignment and Modeling of Articulated 3D Shapes

Black, M., Hirshberg, D., Loper, M., Rachlin, E., Weiss, A.

Febuary 2018, U.S.~Patent 9,898,848 (misc)

Abstract
Present application refers to a method, a model generation unit and a computer program (product) for generating trained models (M) of moving persons, based on physically measured person scan data (S). The approach is based on a common template (T) for the respective person and on the measured person scan data (S) in different shapes and different poses. Scan data are measured with a 3D laser scanner. A generic personal model is used for co-registering a set of person scan data (S) aligning the template (T) to the set of person scans (S) while simultaneously training the generic personal model to become a trained person model (M) by constraining the generic person model to be scan-specific, person-specific and pose-specific and providing the trained model (M), based on the co registering of the measured object scan data (S).

ps

text [BibTex]

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Recent Advances in Wearable Transdermal Delivery Systems

Amjadi, M., Sheykhansari, S., Nelson, B. J., Sitti, M.

Advanced Materials, 30(7):1704530, January 2018 (article)

Abstract
Abstract Wearable transdermal delivery systems have recently received tremendous attention due to their noninvasive, convenient, and prolonged administration of pharmacological agents. Here, the material prospects, fabrication processes, and drug‐release mechanisms of these types of therapeutic delivery systems are critically reviewed. The latest progress in the development of multifunctional wearable devices capable of closed‐loop sensation and drug delivery is also discussed. This survey reveals that wearable transdermal delivery has already made an impact in diverse healthcare applications, while several grand challenges remain.

pi

link (url) DOI [BibTex]

pi Amjadi, M., Sheykhansari, S., Nelson, B. J., Sitti, M. Recent Advances in Wearable Transdermal Delivery Systems Advanced Materials, 30(7):1704530, January 2018 (article)

link (url) DOI [BibTex]

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Acoustic Fabrication via the Assembly and Fusion of Particles

Melde, K., Choi, E., Wu, Z., Palagi, S., Qiu, T., Fischer, P.

Advanced Materials, 30(3):1704507, January 2018 (article)

Abstract
Acoustic assembly promises a route toward rapid parallel fabrication of whole objects directly from solution. This study reports the contact-free and maskless assembly, and fixing of silicone particles into arbitrary 2D shapes using ultrasound fields. Ultrasound passes through an acoustic hologram to form a target image. The particles assemble from a suspension along lines of high pressure in the image due to acoustic radiation forces and are then fixed (crosslinked) in a UV-triggered reaction. For this, the particles are loaded with a photoinitiator by solvent-induced swelling. This localizes the reaction and allows the bulk suspension to be reused. The final fabricated parts are mechanically stable and self-supporting.

pf

link (url) DOI Project Page [BibTex]

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Deep EndoVO: A recurrent convolutional neural network (RCNN) based visual odometry approach for endoscopic capsule robots

Turan, M., Almalioglu, Y., Araujo, H., Konukoglu, E., Sitti, M.

Neurocomputing, 275, pages: 1861 - 1870, January 2018 (article)

Abstract
Ingestible wireless capsule endoscopy is an emerging minimally invasive diagnostic technology for inspection of the GI tract and diagnosis of a wide range of diseases and pathologies. Medical device companies and many research groups have recently made substantial progresses in converting passive capsule endoscopes to active capsule robots, enabling more accurate, precise, and intuitive detection of the location and size of the diseased areas. Since a reliable real time pose estimation functionality is crucial for actively controlled endoscopic capsule robots, in this study, we propose a monocular visual odometry (VO) method for endoscopic capsule robot operations. Our method lies on the application of the deep recurrent convolutional neural networks (RCNNs) for the visual odometry task, where convolutional neural networks (CNNs) and recurrent neural networks (RNNs) are used for the feature extraction and inference of dynamics across the frames, respectively. Detailed analyses and evaluations made on a real pig stomach dataset proves that our system achieves high translational and rotational accuracies for different types of endoscopic capsule robot trajectories.

pi

link (url) DOI [BibTex]

pi Turan, M., Almalioglu, Y., Araujo, H., Konukoglu, E., Sitti, M. Deep EndoVO: A recurrent convolutional neural network (RCNN) based visual odometry approach for endoscopic capsule robots Neurocomputing, 275, pages: 1861 - 1870, January 2018 (article)

link (url) DOI [BibTex]

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Small-scale soft-bodied robot with multimodal locomotion

Hu, W., Lum, G. Z., Mastrangeli, M., Sitti, M.

Nature, 554, pages: 81-85, Nature, January 2018 (article)

Abstract
Untethered small-scale (from several millimetres down to a few micrometres in all dimensions) robots that can non-invasively access confined, enclosed spaces may enable applications in microfactories such as the construction of tissue scaffolds by robotic assembly1, in bioengineering such as single-cell manipulation and biosensing2, and in healthcare3,4,5,6 such as targeted drug delivery4 and minimally invasive surgery3,5. Existing small-scale robots, however, have very limited mobility because they are unable to negotiate obstacles and changes in texture or material in unstructured environments7,8,9,10,11,12,13. Of these small-scale robots, soft robots have greater potential to realize high mobility via multimodal locomotion, because such machines have higher degrees of freedom than their rigid counterparts14,15,16. Here we demonstrate magneto-elastic soft millimetre-scale robots that can swim inside and on the surface of liquids, climb liquid menisci, roll and walk on solid surfaces, jump over obstacles, and crawl within narrow tunnels. These robots can transit reversibly between different liquid and solid terrains, as well as switch between locomotive modes. They can additionally execute pick-and-place and cargo-release tasks. We also present theoretical models to explain how the robots move. Like the large-scale robots that can be used to study locomotion17, these soft small-scale robots could be used to study soft-bodied locomotion produced by small organisms.

pi

link (url) DOI Project Page [BibTex]

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Light‐Driven Janus Hollow Mesoporous TiO2–Au Microswimmers

Sridhar, V., Park, B., Sitti, M.

Advanced Functional Materials, 28(5):1704902, January 2018 (article)

Abstract
Abstract Light‐driven microswimmers have garnered attention for their potential use in various applications, such as environmental remediation, hydrogen evolution, and targeted drug delivery. Janus hollow mesoporous TiO2/Au (JHP–TiO2–Au) microswimmers with enhanced swimming speeds under low‐intensity ultraviolet (UV) light are presented. The swimmers show enhanced swimming speeds both in presence and absence of H2O2. The microswimmers move due to self‐electrophoresis when UV light is incident on them. There is a threefold increase in speed of JHP–TiO2–Au microswimmers in comparison with Janus solid TiO2/Au (JS–TiO2–Au) microswimmers. This increase in their speed is due to the increase in surface area of the porous swimmers and their hollow structure. These microswimmers are also made steerable by using a thin Co magnetic layer. They can be used in potential environmental applications for active photocatalytic degradation of methylene blue and targeted active drug delivery of an anticancer drug (doxurobicin) in vitro in H2O2 solution. Their increased speed from the presence of a hollow mesoporous structure is beneficial for future potential applications, such as hydrogen evolution, selective heterogeneous photocatalysis, and targeted cargo delivery.

pi

link (url) DOI Project Page [BibTex]

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Mechanical Rubbing of Blood Clots Using Helical Robots Under Ultrasound Guidance

Khalil, I. S. M., Mahdy, D., Sharkawy, A. E., Moustafa, R. R., Tabak, A. F., Mitwally, M. E., Hesham, S., Hamdi, N., Klingner, A., Mohamed, A., Sitti, M.

IEEE Robotics and Automation Letters, 3(2):1112-1119, January 2018 (article)

Abstract
A simple way to mitigate the potential negative sideeffects associated with chemical lysis of a blood clot is to tear its fibrin network via mechanical rubbing using a helical robot. Here, we achieve mechanical rubbing of blood clots under ultrasound guidance and using external magnetic actuation. Position of the helical robot is determined using ultrasound feedback and used to control its motion toward the clot, whereas the volume of the clots is estimated simultaneously using visual feedback. We characterize the shear modulus and ultimate shear strength of the blood clots to predict their removal rate during rubbing. Our in vitro experiments show the ability to move the helical robot controllably toward clots using ultrasound feedback with average and maximum errors of 0.84 ± 0.41 and 2.15 mm, respectively, and achieve removal rate of -0.614 ± 0.303 mm3/min at room temperature (25 °C) and -0.482 ± 0.23 mm3/min at body temperature (37 °C), under the influence of two rotating dipole fields at frequency of 35 Hz. We also validate the effectiveness of mechanical rubbing by measuring the number of red blood cells and platelets past the clot. Our measurements show that rubbing achieves cell count of (46 ± 10.9) × 104 cell/ml, whereas the count in the absence of rubbing is (2 ± 1.41) × 104 cell/ml, after 40 min.

pi

link (url) DOI [BibTex]

pi Khalil, I. S. M., Mahdy, D., Sharkawy, A. E., Moustafa, R. R., Tabak, A. F., Mitwally, M. E., Hesham, S., Hamdi, N., Klingner, A., Mohamed, A., Sitti, M. Mechanical Rubbing of Blood Clots Using Helical Robots Under Ultrasound Guidance IEEE Robotics and Automation Letters, 3(2):1112-1119, January 2018 (article)

link (url) DOI [BibTex]

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Distributed Event-Based State Estimation for Networked Systems: An LMI Approach

Muehlebach, M., Trimpe, S.

IEEE Transactions on Automatic Control, 63(1):269-276, January 2018 (article)

am ics

arXiv (extended version) DOI Project Page [BibTex]

am ics Muehlebach, M., Trimpe, S. Distributed Event-Based State Estimation for Networked Systems: An LMI Approach IEEE Transactions on Automatic Control, 63(1):269-276, January 2018 (article)

arXiv (extended version) DOI Project Page [BibTex]

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Method and device for reversibly attaching a phase changing metal to an object

Zhou Ye, G. Z. L. M. S.

US Patent Application US 2018/0021892 A1, January 2018 (patent)

Abstract
A method for reversibly attaching a phase changing metal to an object, the method comprising the steps of: providing a substrate having at least one surface at which the phase changing metal is attached, heating the phase changing metal above a phase changing temperature at which the phase changing metal changes its phase from solid to liquid, bringing the phase changing metal, when the phase changing metal is in the liquid phase or before the phase changing metal is brought into the liquid phase, into contact with the object, permitting the phase changing metal to cool below the phase changing temperature, whereby the phase changing metal becomes solid and the object and the phase changing metal become attached to each other, reheating the phase changing metal above the phase changing temperature to liquefy the phase changing metal, and removing the substrate from the object, with the phase changing metal separating from the object and remaining with the substrate.

pi

US Patent Application Database US Patent Application (PDF) [BibTex]

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Approximate Value Iteration Based on Numerical Quadrature

Vinogradska, J., Bischoff, B., Peters, J.

IEEE Robotics and Automation Letters, 3(2):1330-1337, January 2018 (article)

ei

DOI Project Page [BibTex]

ei Vinogradska, J., Bischoff, B., Peters, J. Approximate Value Iteration Based on Numerical Quadrature IEEE Robotics and Automation Letters, 3(2):1330-1337, January 2018 (article)

DOI Project Page [BibTex]

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Biomimetic Tactile Sensors and Signal Processing with Spike Trains: A Review

Yi, Z., Zhang, Y., Peters, J.

Sensors and Actuators A: Physical, 269, pages: 41-52, January 2018 (article)

ei

DOI Project Page [BibTex]

ei Yi, Z., Zhang, Y., Peters, J. Biomimetic Tactile Sensors and Signal Processing with Spike Trains: A Review Sensors and Actuators A: Physical, 269, pages: 41-52, January 2018 (article)

DOI Project Page [BibTex]

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Measurement of Spectral Functions of Ultracold Atoms in Disordered Potentials

Volchkov, V., Pasek, M., Denechaud, V., Mukhtar, M., Aspect, A., Delande, D., Josse, V.

Physical Review Letters, 120, pages: 060404, American Physical Society (APS), January 2018 (article)

Abstract
We report on the measurement of the spectral functions of noninteracting ultracold atoms in a three-dimensional disordered potential resulting from an optical speckle field. Varying the disorder strength by 2 orders of magnitude, we observe the crossover from the “quantum” perturbative regime of low disorder to the “classical” regime at higher disorder strength, and find an excellent agreement with numerical simulations. The method relies on the use of state-dependent disorder and the controlled transfer of atoms to create well-defined energy states. This opens new avenues for experimental investigations of three-dimensional Anderson localization.

sf

DOI [BibTex]

sf Volchkov, V., Pasek, M., Denechaud, V., Mukhtar, M., Aspect, A., Delande, D., Josse, V. Measurement of Spectral Functions of Ultracold Atoms in Disordered Potentials Physical Review Letters, 120, pages: 060404, American Physical Society (APS), January 2018 (article)

DOI [BibTex]

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Method of fabricating a shape-changeable magentic member, method of producing a shape changeable magnetic member and shape changeable magnetic member

Guo Zhan Lum, Z. Y. M. S.

US Patent Application US 2018/0012693 A1, January 2018 (patent)

Abstract
The present invention relates to a method of fabricating a shape-changeable magnetic member comprising a plurality of segments with each segment being able to be magnetized with a desired magnitude and orientation of magnetization, to a method of producing a shape changeable magnetic member composed of a plurality of segments and to a shape changeable magnetic member.

pi

US Patent Application Database US Patent Application (PDF) [BibTex]

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Die kybernetische Revolution

Schölkopf, B.

15-Mar-2018, Süddeutsche Zeitung, 2018 (misc)

ei

link (url) [BibTex]

ei Schölkopf, B. Die kybernetische Revolution 15-Mar-2018, Süddeutsche Zeitung, 2018 (misc)

link (url) [BibTex]

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Gaussian Processes and Kernel Methods: A Review on Connections and Equivalences

Kanagawa, M., Hennig, P., Sejdinovic, D., Sriperumbudur, B. K.

Arxiv e-prints, arXiv:1805.08845v1 [stat.ML], 2018 (article)

Abstract
This paper is an attempt to bridge the conceptual gaps between researchers working on the two widely used approaches based on positive definite kernels: Bayesian learning or inference using Gaussian processes on the one side, and frequentist kernel methods based on reproducing kernel Hilbert spaces on the other. It is widely known in machine learning that these two formalisms are closely related; for instance, the estimator of kernel ridge regression is identical to the posterior mean of Gaussian process regression. However, they have been studied and developed almost independently by two essentially separate communities, and this makes it difficult to seamlessly transfer results between them. Our aim is to overcome this potential difficulty. To this end, we review several old and new results and concepts from either side, and juxtapose algorithmic quantities from each framework to highlight close similarities. We also provide discussions on subtle philosophical and theoretical differences between the two approaches.

pn

arXiv [BibTex]

pn Kanagawa, M., Hennig, P., Sejdinovic, D., Sriperumbudur, B. K. Gaussian Processes and Kernel Methods: A Review on Connections and Equivalences Arxiv e-prints, arXiv:1805.08845v1 [stat.ML], 2018 (article)

arXiv [BibTex]

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Design and Analysis of the NIPS 2016 Review Process

Shah*, N., Tabibian*, B., Muandet, K., Guyon, I., von Luxburg, U.

Journal of Machine Learning Research, 19(49):1-34, 2018, *equal contribution (article)

ei slt

arXiv link (url) Project Page Project Page [BibTex]

ei slt Shah*, N., Tabibian*, B., Muandet, K., Guyon, I., von Luxburg, U. Design and Analysis of the NIPS 2016 Review Process Journal of Machine Learning Research, 19(49):1-34, 2018, *equal contribution (article)

arXiv link (url) Project Page Project Page [BibTex]

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A Flexible Approach for Fair Classification

Zafar, M. B., Valera, I., Gomez Rodriguez, M., Gummadi, K.

Journal of Machine Learning, 2018 (article) Accepted

ei

Project Page [BibTex]

ei Zafar, M. B., Valera, I., Gomez Rodriguez, M., Gummadi, K. A Flexible Approach for Fair Classification Journal of Machine Learning, 2018 (article) Accepted

Project Page [BibTex]