Header logo is


2023


Hydraulically Amplified Self-healing Electrostatic Actuators
Hydraulically Amplified Self-healing Electrostatic Actuators

Keplinger, C. M., Acome, E. L., Kellaris, N. A., Mitchell, S. K.

(US Patent 11795979B2), October 2023 (patent)

Abstract
An electro-hydraulic actuator includes a deformable shell defining an enclosed internal cavity and containing a liquid dielectric, first and second electrodes on first and second sides, respectively, of the enclosed internal cavity. An electrostatic force between the first and second electrodes upon application of a voltage to one of the electrodes draws the electrodes towards each other to displace the liquid dielectric within the enclosed internal cavity. The shell includes active and inactive areas such that the electrostatic forces between the first and second electrodes displaces the liquid dielectric within the enclosed internal cavity from the active area of the shell to the inactive area of the shell. The first and second electrodes, the deformable shell, and the liquid dielectric cooperate to form a self-healing capacitor, and the liquid dielectric is configured for automatically filling breaches in the liquid dielectric resulting from dielectric breakdown.

rm

link (url) [BibTex]

2023


link (url) [BibTex]


no image
Efficient Sampling from Differentiable Matrix Elements

Kofler, A.

Technical University of Munich, Germany, September 2023 (mastersthesis)

ei

[BibTex]

[BibTex]


High Strain Peano Hydraulically Amplified Self-Healing Electrostatic (HASEL) Transducers
High Strain Peano Hydraulically Amplified Self-Healing Electrostatic (HASEL) Transducers

Keplinger, C. M., Wang, X., Mitchell, S. K.

(US Patent App. 18/138,621), August 2023 (patent)

Abstract
High strain hydraulically amplified self-healing electrostatic transducers having increased maximum theoretical and practical strains are disclosed. In particular, the actuators include electrode configurations having a zipping front created by the attraction of the electrodes that is configured orthogonally to a strain axis along which the actuators. This configuration produces increased strains. In turn, various form factors for the actuator configuration are presented including an artificial circular muscle and a strain amplifying pulley system. Other actuator configurations are contemplated that include independent and opposed electrode pairs to create cyclic activation, hybrid electrode configurations, and use of strain limiting layers for controlled deflection of the actuator.

rm

link (url) [BibTex]


Capacitive Self-Sensing for Electrostatic Transducers with High Voltage Isolation
Capacitive Self-Sensing for Electrostatic Transducers with High Voltage Isolation

Correll, N., Ly, K. D., Kellaris, N. A., Keplinger, C. M.

(US Patent App. 17/928,453), June 2023 (patent)

Abstract
Transducer systems disclosed herein include self-sensing capabilities. In particular, electrostatic transducers include a low voltage electrode and a high voltage electrode. A low voltage sensing unit is coupled with the low voltage electrode of the electrostatic transducer. The low voltage sensing unit is configured to measure a capacitance of the electrostatic transducer, from which displacement of the electrostatic transducer may be calculated. High voltage drive signals received by the high voltage electrode during actuation may be isolated from the low voltage sensing unit. The isolation may be provided by dielectric material of the electrostatic transducer, a voltage suppression component, and/or a voltage suppression module comprising a low impedance ground path. In the event of an electrical failure of the transducer, the low voltage sensing unit may be isolated from high voltages.

rm

link (url) [BibTex]

link (url) [BibTex]


High Strain Peano Hydraulically Amplified Self-healing Electrostatic (HASEL) Transducers
High Strain Peano Hydraulically Amplified Self-healing Electrostatic (HASEL) Transducers

Keplinger, C. M., Wang, X., Mitchell, S. K.

(US Patent 11635094), April 2023 (patent)

Abstract
High strain hydraulically amplified self-healing electrostatic transducers having increased maximum theoretical and practical strains are disclosed. In particular, the actuators include electrode configurations having a zipping front created by the attraction of the electrodes that is configured orthogonally to a strain axis along which the actuators. This configuration produces increased strains. In turn, various form factors for the actuator configuration are presented including an artificial circular muscle and a strain amplifying pulley system. Other actuator configurations are contemplated that include independent and opposed electrode pairs to create cyclic activation, hybrid electrode configurations, and use of strain limiting layers for controlled deflection of the actuator.

rm

link (url) [BibTex]


no image
Intrinsic complexity and mechanisms of expressivity of cortical neurons

Spieler, A. M.

University of Tübingen, Germany, March 2023 (mastersthesis)

ei

[BibTex]

[BibTex]


no image
Towards Generative Machine Teaching

Qui, Z.

Technical University of Munich, Germany, February 2023 (mastersthesis)

ei

[BibTex]

[BibTex]


no image
Generation and Quantification of Spin in Robot Table Tennis

Dittrich, A.

University of Stuttgart, Germany, January 2023 (mastersthesis)

ei

[BibTex]

[BibTex]


An Open-Source Modular Treadmill for Dynamic Force Measurement with Load Dependant Range Adjustment
An Open-Source Modular Treadmill for Dynamic Force Measurement with Load Dependant Range Adjustment

Sarvestani, A., Ruppert, F., Badri-Spröwitz, A.

2023 (unpublished) Submitted

Abstract
Ground reaction force sensing is one of the key components of gait analysis in legged locomotion research. To measure continuous force data during locomotion, we present a novel compound instrumented treadmill design. The treadmill is 1.7 m long, with a natural frequency of 170 Hz and an adjustable range that can be used for humans and small robots alike. Here, we present the treadmill’s design methodology and characterize it in its natural frequency, noise behavior and real-life performance. Additionally, we apply an ISO 376 norm conform calibration procedure for all spatial force directions and center of pressure position. We achieve a force accuracy of ≤ 5.6 N for the ground reaction forces and ≤ 13 mm in center of pressure position.

dlg

arXiv link (url) DOI [BibTex]


no image
Natural Language Processing for Policymaking

Jin, Z., Mihalcea, R.

In Handbook of Computational Social Science for Policy, pages: 141-162, 7, (Editors: Bertoni, E. and Fontana, M. and Gabrielli, L. and Signorelli, S. and Vespe, M.), Springer International Publishing, 2023 (inbook)

ei

DOI [BibTex]

DOI [BibTex]


no image
Microfibers with mushroom-shaped tips for optimal adhesion

Sitti, M., Aksak, B.

2023, US Patent 11,613,674 (patent)

pi

[BibTex]

[BibTex]


Magnetic trap system and method of navigating a microscopic device
Magnetic trap system and method of navigating a microscopic device

Son, D., Ugurlu, M., Bluemer, P., Sitti, M.

2023, US Patent App. 17/871,598 (patent)

pi

[BibTex]

2022


no image
DRY ADHESIVES AND METHODS FOR MAKING DRY ADHESIVES

Metin Sitti, Michael Murphy, Burak Aksak

December 2022, US Patent App. 17/895,334, 2022 (patent)

pi

[BibTex]

2022


[BibTex]


Hydraulically Amplified Self-healing Electrostatic Transducers Harnessing Zipping Mechanism
Hydraulically Amplified Self-healing Electrostatic Transducers Harnessing Zipping Mechanism

Keplinger, C. M., Acome, E. L., Kellaris, N. A., Mitchell, S. K., Morrissey, T. G.

(US Patent 11486421B2), November 2022 (patent)

Abstract
Hydraulically-amplified, self-healing, electrostatic transducers that harness electrostatic and hydraulic forces to achieve various actuation modes. Electrostatic forces between electrode pairs of the transducers generated upon application of a voltage to the electrode pairs draws the electrodes in each pair towards each other to displace a liquid dielectric contained within an enclosed internal cavity of the transducers to drive actuation in various manners. The electrodes and the liquid dielectric form a self-healing capacitor whereby the liquid dielectric automatically fills breaches in the liquid dielectric resulting from dielectric breakdown. Due to the resting shape of the cavity, a zipping-mechanism allows for selectively actuating the electrodes to a desired extent by controlling the voltage supplied.

rm

link (url) [BibTex]

link (url) [BibTex]


no image
Life Improvement Science

Lieder, F., Prentice, M.

In Encyclopedia of Quality of Life and Well-Being Research, Springer, November 2022 (inbook)

re

[BibTex]

[BibTex]


Hydraulically Amplified Self-Healing Electrostatic (HASEL) Pumps
Hydraulically Amplified Self-Healing Electrostatic (HASEL) Pumps

Mitchell, S. K., Acome, E. L., Keplinger, C. M.

(US Patent App. 17/635,339), October 2022 (patent)

Abstract
A pumping system includes a conduit with an inlet region and an outlet region and a first pump coupled with the conduit between the inlet region and the outlet region. The first pump includes a first actuator chamber configured to house at least a first actuator, a first pump chamber aligned along a longitudinal axis of the conduit, wherein the first pump chamber is in fluid communication with the inlet region and the outlet region, and a first flexible diaphragm separating the first actuator chamber from the first pump chamber. Methods for operating the pumping system are also disclosed.

rm

link (url) [BibTex]

link (url) [BibTex]


no image
Investigating Independent Mechanisms in Neural Networks

Liang, W.

Université Paris-Saclay, France, October 2022 (mastersthesis)

ei

[BibTex]

[BibTex]


no image
Causality, causal digital twins, and their applications

Schölkopf, B.

Machine Learning for Science: Bridging Data-Driven and Mechanistic Modelling (Dagstuhl Seminar 22382), (Editors: Berens, Philipp and Cranmer, Kyle and Lawrence, Neil D. and von Luxburg, Ulrike and Montgomery, Jessica), September 2022 (talk)

ei

link (url) DOI [BibTex]

link (url) DOI [BibTex]


no image
Multi-Target Multi-Object Manipulation using Relational Deep Reinforcement Learning

Feil, M.

Technnical University Munich, Germany, September 2022 (mastersthesis)

ei

[BibTex]

[BibTex]


no image
Independent Mechanism Analysis for High Dimensions

Sliwa, J.

University of Tübingen, Germany, September 2022, (Graduate Training Centre of Neuroscience) (mastersthesis)

ei

[BibTex]

[BibTex]


Hydraulically Amplified Self-healing Electrostatic Actuators
Hydraulically Amplified Self-healing Electrostatic Actuators

Keplinger, C. M., Acome, E. L., Kellaris, N. A., Mitchell, S. K.

(US Patent 11408452), August 2022 (patent)

Abstract
An electro-hydraulic actuator includes a deformable shell defining an enclosed internal cavity and containing a liquid dielectric, first and second electrodes on first and second sides, respectively, of the enclosed internal cavity. An electrostatic force between the first and second electrodes upon application of a voltage to one of the electrodes draws the electrodes towards each other to displace the liquid dielectric within the enclosed internal cavity. The shell includes active and inactive areas such that the electrostatic forces between the first and second electrodes displaces the liquid dielectric within the enclosed internal cavity from the active area of the shell to the inactive area of the shell. The first and second electrodes, the deformable shell, and the liquid dielectric cooperate to form a self-healing capacitor, and the liquid dielectric is configured for automatically filling breaches in the liquid dielectric resulting from dielectric breakdown.

rm

link (url) [BibTex]

link (url) [BibTex]


no image
On the Adversarial Robustness of Causal Algorithmic Recourse

Dominguez-Olmedo, R.

University of Tübingen, Germany, August 2022 (mastersthesis)

ei

[BibTex]

[BibTex]


no image
Independent Mechanism Analysis in High-Dimensional Observation Spaces

Ghosh, S.

ETH Zurich, Switzerland, June 2022 (mastersthesis)

ei

[BibTex]

[BibTex]


Composite Layering of Hydraulically Amplified Self-Healing Electrostatic Transducers
Composite Layering of Hydraulically Amplified Self-Healing Electrostatic Transducers

Keplinger, C. M., Mitchell, S. K., Kellaris, N. A., Rothemund, P.

(US Patent App. 17436455), May 2022 (patent)

Abstract
A hydraulically amplified self-healing electrostatic (HASEL) transducer includes a composite, multi-layered structure. In an example, a HASEL transducer includes a dielectric layer including at least one fluid dielectric layer. The dielectric layer includes a first side and a second side opposing the first side. The HASEL transducer further includes a first electrode disposed at the first side of the dielectric layer, a second electrode disposed at the second side of the dielectric layer, a first outer layer disposed at the first electrode opposite the dielectric layer, and a second outer layer disposed at the second electrode opposite the dielectric layer. The first outer layer and second outer layer exhibit different mechanical and electrical properties from the dielectric layer.

rm

link (url) [BibTex]

link (url) [BibTex]


no image
Causal Models for Dynamical Systems

Peters, J., Bauer, S., Pfister, N.

In Probabilistic and Causal Inference: The Works of Judea Pearl, pages: 671-690, 1, Association for Computing Machinery, 2022 (inbook)

ei

arXiv DOI [BibTex]

arXiv DOI [BibTex]


no image
Towards Causal Algorithmic Recourse

Karimi, A. H., von Kügelgen, J., Schölkopf, B., Valera, I.

In xxAI - Beyond Explainable AI: International Workshop, Held in Conjunction with ICML 2020, July 18, 2020, Vienna, Austria, Revised and Extended Papers, pages: 139-166, (Editors: Holzinger, Andreas and Goebel, Randy and Fong, Ruth and Moon, Taesup and Müller, Klaus-Robert and Samek, Wojciech), Springer International Publishing, 2022 (inbook)

ei plg

DOI [BibTex]

DOI [BibTex]


no image
Causality for Machine Learning

Schölkopf, B.

In Probabilistic and Causal Inference: The Works of Judea Pearl, pages: 765-804, 1, Association for Computing Machinery, New York, NY, USA, 2022 (inbook)

ei

arXiv DOI [BibTex]

arXiv DOI [BibTex]


no image
CLEVR-X: A Visual Reasoning Dataset for Natural Language Explanations

Salewski, L., Koepke, A. S., Lensch, H. P. A., Akata, Z.

In xxAI - Beyond Explainable AI: International Workshop, Held in Conjunction with ICML 2020, July 18, 2020, Vienna, Austria, Revised and Extended Papers, pages: 69-88, (Editors: Holzinger, Andreas and Goebel, Randy and Fong, Ruth and Moon, Taesup and Müller, Klaus-Robert and Samek, Wojciech), Springer International Publishing, 2022 (inbook)

ei

DOI [BibTex]

DOI [BibTex]


no image
Voltage dependent investigations on the spin polarization of layered heterostructues

Miller, M.

Universität Stuttgart, Stuttgart, 2022 (mastersthesis)

mms

[BibTex]

[BibTex]

2021


Magnetic Micro-/Nanopropellers  for Biomedicine
Magnetic Micro-/Nanopropellers for Biomedicine

Qiu, T., Jeong, M., Goyal, R., Kadiri, V., Sachs, J., Fischer, P.

In Field-Driven Micro and Nanorobots for Biology and Medicine, pages: 389-410, 16, (Editors: Sun, Y. and Wang, X. and Yu, J.), Springer Nature, November 2021 (inbook)

Abstract
In nature, many bacteria swim by rotating their helical flagella. A particularly promising class of artificial micro- and nano-robots mimic this propeller-like propulsion mechanism to move through fluids and tissues for applications in minimally-invasive medicine. Several fundamental challenges have to be overcome in order to build micro-machines that move similar to bacteria for in vivo applications. Here, we review recent advances of magnetically-powered micro-/nano-propellers. Four important aspects of the propellers – the geometrical shape, the fabrication method, the generation of magnetic fields for actuation, and the choice of biocompatible magnetic materials – are highlighted. First, the fundamental requirements are elucidated that arise due to hydrodynamics at low Reynolds (Re) number. We discuss the role that the propellers’ shape and symmetry play in realizing effective propulsion at low Re. Second, the additive nano-fabrication method Glancing Angle Deposition is discussed as a versatile technique to quickly grow large numbers of designer nano-helices. Third, systems to generate rotating magnetic fields via permanent magnets or electromagnetic coils are presented. And finally, the biocompatibility of the magnetic materials is discussed. Iron-platinum is highlighted due to its biocompatibility and its superior magnetic properties, which is promising for targeted delivery, minimally-invasive magnetic nano-devices and biomedical applications.

pf

link (url) DOI [BibTex]

2021


link (url) DOI [BibTex]


no image
Learning Neural Causal Models with Active Interventions

Scherrer, N.

ETH Zurich, Switzerland, November 2021 (mastersthesis)

ei

[BibTex]

[BibTex]


no image
Study of the Interventional Consistency of Autoencoders

Lanzillotta, G.

ETH Zurich, Switzerland, October 2021 (mastersthesis)

ei

[BibTex]

[BibTex]


no image
Physically Plausible Tracking & Reconstruction of Dynamic Objects

Strecke, M., Stückler, J.

KIT Science Week Scientific Conference & DGR-Days 2021, October 2021 (talk)

ev

[BibTex]

[BibTex]


Skinned multi-infant linear body model
Skinned multi-infant linear body model

Hesse, N., Pujades, S., Romero, J., Black, M.

(US Patent 11,127,163, 2021), September 2021 (patent)

Abstract
A computer-implemented method for automatically obtaining pose and shape parameters of a human body. The method includes obtaining a sequence of digital 3D images of the body, recorded by at least one depth camera; automatically obtaining pose and shape parameters of the body, based on images of the sequence and a statistical body model; and outputting the pose and shape parameters. The body may be an infant body.

ps

[BibTex]

[BibTex]


no image
Electriflow: Augmenting Books With Tangible Animation Using Soft Electrohydraulic Actuators

Purnendu, , Novack, S., Acome, E., Alistar, M., Keplinger, C., Gross, M. D., Bruns, C., Leithinger, D.

In ACM SIGGRAPH 2021 Labs, pages: 1-2, Association for Computing Machinery, SIGGRAPH 2021, August 2021 (inbook)

Abstract
We present Electriflow: a method of augmenting books with tangible animation employing soft electrohydraulic actuators. These actuators are compact, silent and fast in operation, and can be fabricated with commodity materials. They generate an immediate hydraulic force upon electrostatic activation without an external fluid supply source, enabling a simple and self-contained design. Electriflow actuators produce an immediate shape transition from flat to folded state which enabled their seamless integration into books. For the Emerging Technologies exhibit, we will demonstrate the prototype of a book augmented with the capability of tangible animation.

rm

Supplemental Material link (url) DOI [BibTex]

Supplemental Material link (url) DOI [BibTex]


Improving Human Decision-Making by Discovering Efficient Strategies for Hierarchical Planning
Improving Human Decision-Making by Discovering Efficient Strategies for Hierarchical Planning

Heindrich, L., Consul, S., Stojcheski, J., Lieder, F.

Tübingen, Germany, The first edition of Life Improvement Science Conference, June 2021 (talk) Accepted

Abstract
The discovery of decision strategies is an essential part of creating effective cognitive tutors that teach planning and decision-making skills to humans. In the context of bounded rationality, this requires weighing the benefits of different planning operations compared to their computational costs. For small decision problems, it has already been shown that near-optimal decision strategies can be discovered automatically and that the discovered strategies can be taught to humans to increase their performance. Unfortunately, these near-optimal strategy discovery algorithms have not been able to scale well to larger problems due to their computational complexity. In this talk, we will present recent work at the Rationality Enhancement Group to overcome the computational bottleneck of existing strategy discovery algorithms. Our approach makes use of the hierarchical structure of human behavior by decomposing sequential decision problems into two sub-problems: setting a goal and planning how to achieve it. An additional metacontroller component is introduced to switch the current goal when it becomes beneficial. The hierarchical decomposition enables us to discover near-optimal strategies for human planning in larger and more complex tasks than previously possible. We then show in online experiments that teaching the discovered strategies to humans improves their performance in complex sequential decision-making tasks.

re

Project Page [BibTex]

Project Page [BibTex]


no image
Robotic Surgery Training in AR: Multimodal Record and Replay

Krauthausen, F.

pages: 1-147, University of Stuttgart, Stuttgart, May 2021, Study Program in Software Engineering (mastersthesis)

hi

[BibTex]

[BibTex]


no image
An electric machine with two-phase planar Lorentz coils and a ring-shaped Halbach array for high torque density and high-precision applications

Nguyen, V., Javot, B., Kuchenbecker, K. J.

(EP21170679.1), April 2021 (patent)

Abstract
An electric machine, in particular a motor or a generator, comprising a rotor and a stator, wherein the rotor comprises a planar, ring-shaped rotor base element and the stator comprises a planar ring-shaped stator base element, wherein the rotor base element and the stator base element are aligned along an axial axis (Z) of the electric machine, wherein a plurality of magnet elements are arranged around the circumference of the ring-shaped rotor base element forming a Halbach magnet-ring assembly, wherein the Halbach magnet-ring assembly generates a magnetic field (BR) with axial and azimuthal components, wherein a plurality of coils are arranged around the circumference (C) of the ring-shaped stator base element.

hi

Project Page [BibTex]


no image
Hydraulically Amplified Self-Healing Electrostatic Transducers Harnessing Zipping Mechanism

Keplinger, C. M., Acome, E. L., Kellaris, N. A., Mitchell, S. K., Morrissey, T. G.

(US Patent 20210003149A1), January 2021 (patent)

Abstract
Hydraulically-amplified, self-healing, electrostatic transducers that harness electrostatic and hydraulic forces to achieve various actuation modes. Electrostatic forces between electrode pairs of the transducers generated upon application of a voltage to the electrode pairs draws the electrodes in each pair towards each other to displace a liquid dielectric contained within an enclosed internal cavity of the transducers to drive actuation in various manners. The electrodes and the liquid dielectric form a self-healing capacitor whereby the liquid dielectric automatically fills breaches in the liquid dielectric resulting from dielectric breakdown. Due to the resting shape of the cavity, a zipping-mechanism allows for selectively actuating the electrodes to a desired extent by controlling the voltage supplied.

rm

link (url) [BibTex]

link (url) [BibTex]


no image
Direct detection of spin Hall effect induced torques in platinum/ferromagnetic bilayer systems

Alten, F.

Universität Stuttgart, Stuttgart, January 2021 (mastersthesis)

mms

[BibTex]


Sensor arrangement for sensing forces and methods for fabricating a sensor arrangement and parts thereof
Sensor arrangement for sensing forces and methods for fabricating a sensor arrangement and parts thereof

Sun, H., Martius, G., Kuchenbecker, K. J.

(PCT/EP2021/050230), Max Planck Institute for Intelligent Systems, Max Planck Ring 4, January 2021 (patent)

Abstract
The invention relates to a vision-based haptic sensor arrangement for sensing forces, to a method for fabricating a top portion of a sensor arrangement, and to a method for fabricating a sensor arrangement.

al hi

Project Page [BibTex]

Project Page [BibTex]


Method for force inference, method for training a feed-forward neural network, force inference module, and sensor arrangement
Method for force inference, method for training a feed-forward neural network, force inference module, and sensor arrangement

Sun, H., Martius, G., Kuchenbecker, K. J.

(PCT/EP2021/050231), Max Planck Institute for Intelligent Systems, Max Planck Ring 4, January 2021 (patent)

Abstract
The invention relates to a method for force inference of a sensor arrangement for sensing forces, to a method for training a feed-forward neural network, to a force inference module, and to a sensor arrangement.

al hi

Project Page [BibTex]

Project Page [BibTex]


Slippery micropropellers penetrate the vitreous humor
Slippery micropropellers penetrate the vitreous humor

Wu, Z., Qiu, T., Fischer, P.

(US20210170056A1), 2021 (patent)

Abstract
Microparticles actively propel through the vitreous humour and reach the retina in porcine eyes. The slippery micro helical propellers are constructed by the combination of glancing angle deposition technique and the fusion of the slippery liquid layer. The magnetically propulsion in the vitreous humour relies on the matched size of the propeller to the collagen network of the vitreous, and the anti-adhesion coating of the collagen fiber bundles. Clinical optical coherence tomography observed the displacement of the slippery micropropellers through the vitreous to the macular area on the retina. The slippery micropropellers realize the controllable massive movements to the retina in 30 mins, while exerting the travelling distance of above one centimeter. The injection of the slippery micropropellers, the magnetically-powered controllable propulsion in the vitreous, and the optical coherence tomography imaging technique, constitute an intact method for rapid targeted ocular delivery, providing a promising approach towards ophthalmologic applications.

pf

[BibTex]