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Department Talks

Human Tactile Afferent Responses during the Onset of Slip

Talk
  • 28 January 2020 • 11:00 12:00
  • Benoit Delhaye
  • MPI-IS Stuttgart, Heisenbergstr. 3, Room 2P4

During manipulation, humans adjust the amount of force applied to an object depending on friction: they exert a stronger grip for slippery surfaces and a looser grip for sticky surfaces. However, the neural mechanisms signaling friction remain unclear. To fill this gap, we recorded the response of human tactile afferent during the onset of slip against flat surfaces of different frictions. We observed that some afferents responded to partial slip events occurring during transition from a stuck to a slipping contact, and potentially signaling the impending slip.

Organizers: Katherine J. Kuchenbecker Ilona Jacobi


  • Nataliya Rokhmanova
  • MPI-IS Stuttgart, Heisenbergstr. 3, Room 2P4

Wearable sensing and feedback devices are becoming increasingly ubiquitous for measuring human movement in research laboratories, medical clinics, and in consumer goods. Advances in computation and miniaturization have enabled sensing for gait assessment; these technologies are then used in interventions to provide feedback that facilitates changes in gait or enhances sensory capabilities. This talk will focus on vibration as the primary method of providing feedback. I will discuss the use of vibrotactile arrays to communicate plantar foot pressure in users of lower-limb prosthetics, as a synthetic form of sensory feedback. Wearable vibrating units can also be used as a cue to retrain gait, and I will describe my preliminary work in gait retraining as a conservative treatment for knee osteoarthritis. This talk will cover the development and evaluation of these haptic devices and establish their impact within the greater context of clinical biomechanics.

Organizers: Katherine J. Kuchenbecker Ilona Jacobi


Search-Based Planning for High-Dimensional Robotic Systems

Talk
  • 24 January 2020 • 11:00 12:00
  • Maxim Likhachev
  • MPI-IS Stuttgart, Heisenbergstr. 3, Room 2P4

Search-based Planning refers to planning by constructing a graph from systematic discretization of the state- and action-space of a robot and then employing a heuristic search to find an optimal path from the start to the goal vertex in this graph. This paradigm works well for low-dimensional robotic systems such as mobile robots and provides rigorous guarantees on solution quality. However, when it comes to planning for higher-dimensional robotic systems such as mobile manipulators, humanoids and ground and aerial vehicles navigating at high-speed, Search-based Planning has been typically thought of as infeasible. In this talk, I will describe some of the research that my group has done into changing this thinking. In particular, I will focus on two different principles. First, constructing multiple lower-dimensional abstractions of robotic systems, solutions to which can effectively guide the overall planning process using Multi-Heuristic A*, an algorithm recently developed by my group. Second, using offline pre-processing to provide a *provably* constant-time online planning for repetitive planning tasks. I will present algorithmic frameworks that utilize these principles, describe their theoretical properties, and demonstrate their applications to a wide range of physical high-dimensional robotic systems.

Organizers: Katherine J. Kuchenbecker Ilona Jacobi


  • Dr. Katherine J. Kuchenbecker
  • MPI Campus in Tübingen - Lecture hall in the Max Planck House

Our scientific understanding of haptic interaction is still evolving, both because what you feel greatly depends on how you move, and because engineered sensors, actuators, and algorithms typically struggle to match human capabilities. Consequently, few computer and machine interfaces provide the human operator with high-fidelity touch feedback or carefully analyze the physical signals generated during haptic interactions, limiting their usability. The crucial role of the sense of touch is also deeply appreciated by researchers working to create autonomous robots that can competently manipulate everyday objects and safely interact with humans in unstructured environments.


Automatic Authoring of Haptic Content

IS Colloquium
  • 06 December 2019 • 11:00 12:00
  • Seungmoon Choi, Ph.D.
  • MPI-IS Stuttgart, Heisenbergstr. 3, Room 2R4 (Werner-Köster lecture hall)

Providing rich and immersive physical experiences to users has become an essential component in many computer-interactive applications, where haptics plays a central role. However, as with other sensory modalities, modeling and rendering good haptic experiences with plausible physicality is a very demanding task in terms of the cost associated with modeling and authoring, not to mention the cost for development. No general and widely-used solutions exist yet for that; most designers and developers rely on their in-house programs, or even worse, manual coding. This talk will introduce the research conducted by the speaker in order to facilitate the authoring of haptic content. In particular, it will focus on automatic synthesis algorithms of vibrotactile effects and motion effects from audiovisual content, as well as some relevant issues in haptic perception.

Organizers: Katherine J. Kuchenbecker


From Fingertip Skin Mechanics to Dexterous Object Manipulation

IS Colloquium
  • 25 September 2019 • 13:00 14:00
  • Jean-Louis Thonnard
  • MPI-IS Stuttgart, Heisenbergstr. 3, Room 2P4

Fingertip skin friction plays a critical role during object manipulation. We will describe a simple and reliable method to estimate the fingertip static coefficient of friction (CF) continuously and quickly during object manipulation, and we will describe a global expression of the CF as a function of the normal force and fingertip moisture. Then we will show how skin hydration modifies the skin deformation dynamics during grip-like contacts. Certain motor behaviours observed during object manipulation could be explained by the effects of skin hydration. Then the biomechanics of the partial slip phenomenon will be described, and we will examine how this partial slip phenomenon is related to the subjective perception of fingertip slip.

Organizers: Katherine J. Kuchenbecker David Gueorguiev


  • Ernest (Ted) Gomez, MD, MTR
  • MPI-IS Stuttgart, Heisenbergstr. 3, Room 2P4

Surgery is a demanding activity that places a human life in the hands of others. However, innovations in minimally invasive surgery have physically separated surgeons' hands from their patients, creating the need for surgeons and their tools to develop both natural and artificial haptic intelligence. This lecture examines the essential role of haptic intelligence in skill development for laparoscopic and robotic surgery.

Organizers: Katherine J. Kuchenbecker


A New Framework to Understanding Biological Vision

IS Colloquium
  • 03 September 2019 • 11:00 12:00
  • Zhaoping Li
  • MPI-IS Stuttgart, Heisenbergstr. 3, Room 2P4

Visual attention selects a tiny amount of information that can be deeply processed by the brain, and gaze shifts bring the selected visual object to fovea, the center of the visual field, for better visual decoding or recognition of the selected objects. Therefore, central and peripheral vision should differ qualitatively in visual decoding, rather than just quantitatively in visual acuity.

Organizers: Katherine J. Kuchenbecker


  • Gunhyuk Park
  • MPI-IS Stuttgart, Heisenbergstr. 3, Room 2P4

Many hapticians have designed and implemented haptic effects to various user interactions. For several decades, hapticians have proved that the haptic feedback can improve multiple facets of user experience including task performance, analyzing and utilizing user perception, and substituting other sensory modalities. Among them, this talk introduces two representative rendering methods to provide vibrotactile effects to users: 2D phantom sensation that makes a user perceive illusive tactile perception by using multiple real vibrotactile actuators and vibrotactile dimensional reduction that reduces 3D acceleration data from real interactions to 1D vibrations for maximizing its realism and similarity.

Organizers: Katherine J. Kuchenbecker


  • Yasemin Vardar
  • 2P4 in Heisenbergstr. 3

Sign-Up! is a career-building program for female post-docs in the Max Planck Society. This program aims to prepare post-doctoral researchers for their future scientific careers by several interactive training sessions and networking activities. As a selected member of this program, I will summarize the workshops that I participated in this year. My talk will cover topics about success factors in scientific careers, career planning, professional communication and leadership, self-presentation, and research funding.

Organizers: Katherine J. Kuchenbecker