Niko Kleer

dblp:256/9168 · DBLP profile ↗
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6ranked-venue papers
3as first author
5since 2021 · last 2024
0000-0003-4288-4724ORCID · corroborated

Domains — the database's venue-derived domains; a paper can count in several

Artificial intelligence and machine learning · 5 · 3 first-author · 4 since 2021Systems, architecture and hardware · 3 · 2 first-author · 3 since 2021Human-computer interaction and ubiquitous computing · 2 · 1 first-author · 2 since 2021Databases, data management, data science and information retrieval · 1Applied, interdisciplinary, general and emerging computing · 1 · 1 first-author · 1 since 2021
YearPublicationVenuePosition
2024 Towards a Surgeon-in-the-Loop Ophthalmic Robotic Apprentice using Reinforcement and Imitation Learning
abstract
Robot-assisted surgical systems have demonstrated significant potential in enhancing surgical precision and minimizing human errors. However, existing systems cannot accommodate individual surgeons’ unique preferences and requirements. Additionally, they primarily focus on general surgeries (e.g., laparoscopy) and are unsuitable for highly precise microsurgeries, such as ophthalmic procedures. Thus, we propose an image-guided approach for surgeon-centered autonomous agents that can adapt to the individual surgeon’s skill level and preferred surgical techniques during ophthalmic cataract surgery. Our approach trains reinforcement and imitation learning agents simultaneously using curriculum learning approaches guided by image data to perform all tasks of the incision phase of cataract surgery. By integrating the surgeon’s actions and preferences into the training process, our approach enables the robot to implicitly learn and adapt to the individual surgeon’s unique techniques through surgeon-in-the-loop demonstrations. This results in a more intuitive and personalized surgical experience for the surgeon while ensuring consistent performance for the autonomous robotic apprentice. We define and evaluate the effectiveness of our approach in a simulated environment using our proposed metrics and highlight the trade-off between a generic agent and a surgeon-centered adapted agent. Finally, our approach has the potential to extend to other ophthalmic and microsurgical procedures, opening the door to a new generation of surgeon-in-the-loop autonomous surgical robots. We provide an open-source simulation framework for future development and reproducibility at https://github.com/amrgomaaelhady/CataractAdaptSurgRobot.
Amr Gomaa, Bilal Mahdy, Niko Kleer, Antonio Krüger
IROS3
2024 Bridging the Gap to Natural Language-based Grasp Predictions through Semantic Information Extraction
abstract
Enabling multi-fingered robots to choose an appropriate grasp on an object from natural language instructions poses great difficulties for such systems. The diversity, imprecision, and limited information contained in the language make this task particularly challenging. However, speech serves humans as a natural communication interface that can aid robots in adapting to the environment more easily. Therefore, providing robots with relevant data about the objects they interact with is essential for them to understand how to carry out object manipulation tasks. By leveraging Named Entity Recognition (NER) to automatically extract semantic data, our work introduces a novel approach to text-based grasp predictions. Our methodology involves a multistage learning approach using a semantic information extractor that provides significant features to a grasp prediction model. To assess the effectiveness of our approach, we conducted experiments on an existing corpus and two corpora generated by ChatGPT. Our results demonstrate superior performance compared to similar grasp prediction models while overcoming limitations in the literature. Additionally, we open-source our training data for reproducibility and future research advancement.
Niko Kleer, Martin Feick, Amr Gomaa, Michael Feld, Antonio Krüger
IROS1
2024 Incorporation of the Intended Task into a Vision-based Grasp Type Predictor for Multi-fingered Robotic Grasping
abstract
Robots that make use of multi-fingered or fully anthropomorphic end-effectors can engage in highly complex manipulation tasks. However, the choice of a suitable grasp for manipulating an object is strongly influenced by factors such as the physical properties of an object and the intended task. This makes predicting an appropriate grasping pose for carrying out a concrete task notably challenging. At the same time, current grasp type predictors rarely consider the task as a part of the prediction process. This work proposes a learning model that considers the task in addition to an object’s visual features for predicting a suitable grasp type. Furthermore, we generate a synthetic dataset by simulating robotic grasps on 3D object models based on the BarrettHand end-effector. With an angular similarity of 0.9 and above, our model achieves competitive prediction results compared to grasp type predictors that do not consider the intended task for learning grasps. Finally, to foster research in the field, we make our synthesized dataset available to the research community.
Niko Kleer, Ole Keil, Martin Feick, Amr Gomaa, Tim Schwartz, Michael Feld
RO-MAN1
2022 Leveraging Publicly Available Textual Object Descriptions for Anthropomorphic Robotic Grasp Predictions
abstract
Robotic systems using anthropomorphic end-effectors face tremendous challenges choosing a suitable pose for grasping an object. The fact that the choice of a grasp is influenced by the physical properties of an object, the intended task, and the environment results in a considerable amount of variables. The majority of models targeted towards enabling such robots to determine a suitable grasping pose rely on computer vision techniques, sometimes complemented by textual data. This paper investigates the potential of publicly available textual descriptions to predict a suitable grasping pose for anthropomorphic end-effectors. To this end, we have retrieved textual descriptions from Wikipedia, Wiktionary, and WordNet as well as a number of well-known dictionaries for 100 everyday objects. We analyze and compare the prediction quality of multiple learning methods while showing that a support vector machine-based approach can utilize this data for achieving a prediction accuracy above 0.75. Finally, we make our collected data available to the research community.
Niko Kleer, Martin Feick, Michael Feld
IROS1
2021 Visuo-haptic Illusions for Linear Translation and Stretching using Physical Proxies in Virtual Reality
abstract
Providing haptic feedback when manipulating virtual objects is an essential part of immersive virtual reality experiences; however, it is challenging to replicate all of an object's properties and characteristics. We propose the use of visuo-haptic illusions alongside physical proxies to enhance the scope of proxy-based interactions with virtual objects. In this work, we focus on two manipulation techniques, linear translation and stretching across different distances, and investigate how much discrepancy between the physical proxy and the virtual object may be introduced without participants noticing. In a study with 24 participants, we found that manipulation technique and travel distance significantly affect the detection thresholds, and that visuo-haptic illusions impact performance and accuracy. We show that this technique can be used to enable functional proxy objects that act as stand-ins for multiple virtual objects, illustrating the technique through a showcase VR-DJ application.
Martin Feick, Niko Kleer, André Zenner, Anthony Tang 0001, Antonio Krüger
CHI2
2020 Entities with Quantities: Extraction, Search, and Ranking
abstract
Quantities are more than numeric values. They represent measures for entities, expressed in numbers with associated units. Search queries often include quantities, such as athletes who ran 200m under 20 seconds or companies with quarterly revenue above $2 Billion. Processing such queries requires understanding the quantities, where capturing the surrounding context is an essential part of it. Although modern search engines or QA systems handle entity-centric queries well, they consider numbers and units as simple keywords, and therefore fail to understand the condition (less than, above, etc.), the unit of interest (seconds, dollar, etc.), and the context of the quantity (200m race, quarterly revenue, etc.) As a result, they cannot generate the correct candidate answers. In this work, we demonstrate a prototype QA system, called Qsearch, that can handle advanced queries with quantity constraints using the common cues present in both query and the text sources.
Vinh Thinh Ho, Koninika Pal, Niko Kleer, Klaus Berberich, Gerhard Weikum
WSDM3