Gerhard Kraetzschmar | Bonn-Rhein-Sieg University of Applied Sciences (original) (raw)

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Papers by Gerhard Kraetzschmar

Research paper thumbnail of Distributed Reason Maintenance for Multiagent Systems

Research paper thumbnail of Design and development of a benchmarking testbed for the Factory of the Future

2015 IEEE 20th Conference on Emerging Technologies & Factory Automation (ETFA), 2015

Research paper thumbnail of Challenges in finding ways to get the job done

Research paper thumbnail of PROBABILISTIC QUADTREES FOR VARIABLE-RESOLUTION MAPPING OF LARGE ENVIRONMENTS

Probabilistic occupancy grids are a common and well-proven spatial representation used in robot m... more Probabilistic occupancy grids are a common and well-proven spatial representation used in robot mapping. However, representing very large environments with high resolution can still impose prohibitive memory requirements. A quadtree is a well-known data structure able to achieve compact representations of large two-dimensional binary arrays. We extend this idea and present probabilistic quadtrees for efficient representation and storage of probabilistic occupancy maps. We also discuss the implementation of probabilistic quadtrees and their integration into our robotic middleware system Miro.

Research paper thumbnail of Managing Multiple Contexts Efficiently

Research paper thumbnail of The Ulm Robotics Week

Research paper thumbnail of Interview mit Sebastian Thrun

Research paper thumbnail of Interview mit Hiroaki Kitano

Research paper thumbnail of Supporting Assumption-Based Reasoning in a Distributed Environment

Within the pede project we investigate the generation and execution of plans in distributed envir... more Within the pede project we investigate the generation and execution of plans in distributed environments. As our approach is based on multi-agent systems with some or all agents performing assumption-based reasoning, we ran into the distributed belief revision problem. In order to build planning and executing agents that are able to safely perform their tasks in a highly dynamic environment, a mechanism to support the revision of decisions is required.

Research paper thumbnail of Affordance-Based Reasoning in Robot Task Planning

Humans are able to come up with plans to achieve their goals, and to adapt these plans to changes... more Humans are able to come up with plans to achieve their goals, and to adapt these plans to changes in their environment, finding fixes, alternatives and taking advantages of opportunities without much deliberation. For example, they may use a tea kettle instead of a watering can to water the plants, or a mug instead of a glass to serve water. Despite decades of research, artificial agents are not as robust or as flexible. In this work, we introduce three reasoning phases that use affordances to enable such robustness and flexibility in robot task planning. The first phase generates a focused planning problem. The second phase expands the domain where necessary while the third and final reasoning phase uses affordances during plan execution and monitoring. This is accomplished by combining Hierarchical Task Network planning, description logics, and a robust execution/monitoring system.

Research paper thumbnail of Autonome Mobile Systeme - Serviceteil

Research paper thumbnail of Motivation for Free - Zum Motivationsfaktor von internationalen RoboCupJunior-Wettbewerben

Motivation ist eine notwendige Vo raussetzung für Lernen. Sind die Lernenden gut motiviert, könne... more Motivation ist eine notwendige Vo raussetzung für Lernen. Sind die Lernenden gut motiviert, können wir auf Lernerfolg hoffen. Andernfalls können wir eigentlich gleich aufhören. Die Ve rwendung vonR obotern in der Ausbildung hat sich als hervorragendes Werkzeug zur Motivation vonS tudierenden aller Altersstufen von8 bis 80 erwiesen. Dieser Aufsatz beschreibt die Nutzung vonW ettbewerben, um die Motivation der Studierenden über einen längeren Zeitraum zu erhalten, waswiederum die Chance erhöht, dass die Studierenden Wissen über eine Thematik vertiefen und ein dauerhaftes Interesse am Fach entwickeln. Im speziellen beschreiben wir die zugrundeliegenden Ideen der verschiedenen Wettbewerbe im RoboCupJunior,die genau zu diesem Zweck entwickelt wurden und weltweit genutzt werden. Weltweit schätzungsweise mehr als 2000 Teams vonSchülerinnen und Schüler haben im Jahr 2004 an solchen Wettbewerben teilgenommen, und die Teilnehmerzahlen steigen weiter.

Research paper thumbnail of Unified Closed Form Inverse Kinematics for the KUKA youBot

Mobile manipulators are of high interest to industry because of the increased flexibility and eff... more Mobile manipulators are of high interest to industry because of the increased flexibility and effectiveness they offer. The combination and coordination of the mobility provided by a mobile platform and of the manipulation capabilities provided by a robot arm leads to complex analytical problems for research. These problems can be studied very well on the KUKA youBot, a mobile manipulator designed for education and research applications. Issues still open in research include solving the inverse kinematics problem for the unified kinematics of the mobile manipulator, including handling the kinematic redundancy introduced by the holonomic platform of the KUKA youBot. As the KUKA youBot arm has only 5 degrees of freedom, a unified platform and manipulator system is needed to compensate for the missing degree of freedom. We present the KUKA youBot as an 8 degree of freedom serial kinematic chain, suggest appropriate redundancy parameters, and solve the inverse kinematics for the 8 degre...

Research paper thumbnail of The Role of Functional Affordances in Socializing Robots

International Journal of Social Robotics, 2015

ABSTRACT Just as humans behave according to the social norms of their groups, autonomous systems ... more ABSTRACT Just as humans behave according to the social norms of their groups, autonomous systems that become part of these groups also need to behave in socially-expected and accepted ways. For humans these social norms are learned through interaction with members of the group. In this work, we propose that the functional affordances of objects, what objects are meant to be used for, provide us with a starting point for the socialization of such agents. We model these functional affordances in description logics and show how this enables the socially-expected human behavior of substituting objects as needed to achieve a goal. In addition, we propose to combine these affordances with conceptual similarity and proximity in order to make more complex substitutions, which are socially acceptable in their given context. Finally, we describe how their use would allow the agent to take advantage of opportunities and how they are modified and extended through interaction with humans.

Research paper thumbnail of Socializing Robots: The Role of Functional Affordances

Just as humans behave according to the social norms of their groups, autonomous systems that beco... more Just as humans behave according to the social norms of their groups, autonomous systems that become part of these groups also need to behave in socially-expected and accepted ways. For humans these social norms are learned through interaction with members of the group. In this work, we propose that the functional affordances of objects, what objects are meant to be used for, provide us with a starting point for the socialization of such agents. We model these functional affordances in Description Logics (DL) and show how this enables the socially-expected human behavior of substituting objects as needed to achieve a goal. In addition, we propose to combine these affordances with conceptual similarity and proximity in order to make more complex substitutions, which are socially acceptable in their given context. Finally, we describe how their use would allow the agent to take advantage of opportunities and how they are modified and extended through interaction with humans.

Research paper thumbnail of Robust and Computationally Efficient Navigation in Domestic Environments

Presented in this paper is a complete system for robust autonomous navigation in cluttered and dy... more Presented in this paper is a complete system for robust autonomous navigation in cluttered and dynamic environments. It consists of computationally efficient approaches to the problems of simultaneous localization and mapping, path planning, and motion control, all based on a memory-efficient environment representation. These components have been implemented and integrated with additional components for human-robot interaction and object manipulation on a mobile manipulation platform for service robot applications. The resulting system performed very successfully in the 2008 RoboCup@Home competition.

Research paper thumbnail of Managing multiple contexts efficiently

Research paper thumbnail of Educational Robotics: On the Role of Robotics in Learning and Education

Motivation is a key ingredient for learning: Only if the learner is motivated, successful learnin... more Motivation is a key ingredient for learning: Only if the learner is motivated, successful learning is possible. Educational robotics has proven to be an excellent tool for motivating students at all ages from 8 to 80. Robot competitions for kids, like RoboCupJunior, are instrumental to sustain motivation over a significant period of time. This increases the chances that the learner acquires more in-depth knowledge about the subject area and develops a genuine interest in the field.

Research paper thumbnail of Distributed Reason Maintenance for Multiagent Systems

Research paper thumbnail of PROBABILISTIC QUADTREES FOR VARIABLE-RESOLUTION MAPPING OF LARGE ENVIRONMENTS

Probabilistic occupancy grids are a common and well-proven spatial representation used in robot m... more Probabilistic occupancy grids are a common and well-proven spatial representation used in robot mapping. However, representing very large environ- ments with high resolution can still impose prohibitive memory requirements. A quadtree is a well-known data structure able to achieve compact representations of large two-dimensional binary arrays. We extend this idea and present probabilistic quadtrees for ecient representation and storage of probabilistic occupancy maps. We also discuss the implementation of probabilistic quadtrees and their integration into our robotic middleware system Miro.

Research paper thumbnail of Distributed Reason Maintenance for Multiagent Systems

Research paper thumbnail of Design and development of a benchmarking testbed for the Factory of the Future

2015 IEEE 20th Conference on Emerging Technologies & Factory Automation (ETFA), 2015

Research paper thumbnail of Challenges in finding ways to get the job done

Research paper thumbnail of PROBABILISTIC QUADTREES FOR VARIABLE-RESOLUTION MAPPING OF LARGE ENVIRONMENTS

Probabilistic occupancy grids are a common and well-proven spatial representation used in robot m... more Probabilistic occupancy grids are a common and well-proven spatial representation used in robot mapping. However, representing very large environments with high resolution can still impose prohibitive memory requirements. A quadtree is a well-known data structure able to achieve compact representations of large two-dimensional binary arrays. We extend this idea and present probabilistic quadtrees for efficient representation and storage of probabilistic occupancy maps. We also discuss the implementation of probabilistic quadtrees and their integration into our robotic middleware system Miro.

Research paper thumbnail of Managing Multiple Contexts Efficiently

Research paper thumbnail of The Ulm Robotics Week

Research paper thumbnail of Interview mit Sebastian Thrun

Research paper thumbnail of Interview mit Hiroaki Kitano

Research paper thumbnail of Supporting Assumption-Based Reasoning in a Distributed Environment

Within the pede project we investigate the generation and execution of plans in distributed envir... more Within the pede project we investigate the generation and execution of plans in distributed environments. As our approach is based on multi-agent systems with some or all agents performing assumption-based reasoning, we ran into the distributed belief revision problem. In order to build planning and executing agents that are able to safely perform their tasks in a highly dynamic environment, a mechanism to support the revision of decisions is required.

Research paper thumbnail of Affordance-Based Reasoning in Robot Task Planning

Humans are able to come up with plans to achieve their goals, and to adapt these plans to changes... more Humans are able to come up with plans to achieve their goals, and to adapt these plans to changes in their environment, finding fixes, alternatives and taking advantages of opportunities without much deliberation. For example, they may use a tea kettle instead of a watering can to water the plants, or a mug instead of a glass to serve water. Despite decades of research, artificial agents are not as robust or as flexible. In this work, we introduce three reasoning phases that use affordances to enable such robustness and flexibility in robot task planning. The first phase generates a focused planning problem. The second phase expands the domain where necessary while the third and final reasoning phase uses affordances during plan execution and monitoring. This is accomplished by combining Hierarchical Task Network planning, description logics, and a robust execution/monitoring system.

Research paper thumbnail of Autonome Mobile Systeme - Serviceteil

Research paper thumbnail of Motivation for Free - Zum Motivationsfaktor von internationalen RoboCupJunior-Wettbewerben

Motivation ist eine notwendige Vo raussetzung für Lernen. Sind die Lernenden gut motiviert, könne... more Motivation ist eine notwendige Vo raussetzung für Lernen. Sind die Lernenden gut motiviert, können wir auf Lernerfolg hoffen. Andernfalls können wir eigentlich gleich aufhören. Die Ve rwendung vonR obotern in der Ausbildung hat sich als hervorragendes Werkzeug zur Motivation vonS tudierenden aller Altersstufen von8 bis 80 erwiesen. Dieser Aufsatz beschreibt die Nutzung vonW ettbewerben, um die Motivation der Studierenden über einen längeren Zeitraum zu erhalten, waswiederum die Chance erhöht, dass die Studierenden Wissen über eine Thematik vertiefen und ein dauerhaftes Interesse am Fach entwickeln. Im speziellen beschreiben wir die zugrundeliegenden Ideen der verschiedenen Wettbewerbe im RoboCupJunior,die genau zu diesem Zweck entwickelt wurden und weltweit genutzt werden. Weltweit schätzungsweise mehr als 2000 Teams vonSchülerinnen und Schüler haben im Jahr 2004 an solchen Wettbewerben teilgenommen, und die Teilnehmerzahlen steigen weiter.

Research paper thumbnail of Unified Closed Form Inverse Kinematics for the KUKA youBot

Mobile manipulators are of high interest to industry because of the increased flexibility and eff... more Mobile manipulators are of high interest to industry because of the increased flexibility and effectiveness they offer. The combination and coordination of the mobility provided by a mobile platform and of the manipulation capabilities provided by a robot arm leads to complex analytical problems for research. These problems can be studied very well on the KUKA youBot, a mobile manipulator designed for education and research applications. Issues still open in research include solving the inverse kinematics problem for the unified kinematics of the mobile manipulator, including handling the kinematic redundancy introduced by the holonomic platform of the KUKA youBot. As the KUKA youBot arm has only 5 degrees of freedom, a unified platform and manipulator system is needed to compensate for the missing degree of freedom. We present the KUKA youBot as an 8 degree of freedom serial kinematic chain, suggest appropriate redundancy parameters, and solve the inverse kinematics for the 8 degre...

Research paper thumbnail of The Role of Functional Affordances in Socializing Robots

International Journal of Social Robotics, 2015

ABSTRACT Just as humans behave according to the social norms of their groups, autonomous systems ... more ABSTRACT Just as humans behave according to the social norms of their groups, autonomous systems that become part of these groups also need to behave in socially-expected and accepted ways. For humans these social norms are learned through interaction with members of the group. In this work, we propose that the functional affordances of objects, what objects are meant to be used for, provide us with a starting point for the socialization of such agents. We model these functional affordances in description logics and show how this enables the socially-expected human behavior of substituting objects as needed to achieve a goal. In addition, we propose to combine these affordances with conceptual similarity and proximity in order to make more complex substitutions, which are socially acceptable in their given context. Finally, we describe how their use would allow the agent to take advantage of opportunities and how they are modified and extended through interaction with humans.

Research paper thumbnail of Socializing Robots: The Role of Functional Affordances

Just as humans behave according to the social norms of their groups, autonomous systems that beco... more Just as humans behave according to the social norms of their groups, autonomous systems that become part of these groups also need to behave in socially-expected and accepted ways. For humans these social norms are learned through interaction with members of the group. In this work, we propose that the functional affordances of objects, what objects are meant to be used for, provide us with a starting point for the socialization of such agents. We model these functional affordances in Description Logics (DL) and show how this enables the socially-expected human behavior of substituting objects as needed to achieve a goal. In addition, we propose to combine these affordances with conceptual similarity and proximity in order to make more complex substitutions, which are socially acceptable in their given context. Finally, we describe how their use would allow the agent to take advantage of opportunities and how they are modified and extended through interaction with humans.

Research paper thumbnail of Robust and Computationally Efficient Navigation in Domestic Environments

Presented in this paper is a complete system for robust autonomous navigation in cluttered and dy... more Presented in this paper is a complete system for robust autonomous navigation in cluttered and dynamic environments. It consists of computationally efficient approaches to the problems of simultaneous localization and mapping, path planning, and motion control, all based on a memory-efficient environment representation. These components have been implemented and integrated with additional components for human-robot interaction and object manipulation on a mobile manipulation platform for service robot applications. The resulting system performed very successfully in the 2008 RoboCup@Home competition.

Research paper thumbnail of Managing multiple contexts efficiently

Research paper thumbnail of Educational Robotics: On the Role of Robotics in Learning and Education

Motivation is a key ingredient for learning: Only if the learner is motivated, successful learnin... more Motivation is a key ingredient for learning: Only if the learner is motivated, successful learning is possible. Educational robotics has proven to be an excellent tool for motivating students at all ages from 8 to 80. Robot competitions for kids, like RoboCupJunior, are instrumental to sustain motivation over a significant period of time. This increases the chances that the learner acquires more in-depth knowledge about the subject area and develops a genuine interest in the field.

Research paper thumbnail of Distributed Reason Maintenance for Multiagent Systems

Research paper thumbnail of PROBABILISTIC QUADTREES FOR VARIABLE-RESOLUTION MAPPING OF LARGE ENVIRONMENTS

Probabilistic occupancy grids are a common and well-proven spatial representation used in robot m... more Probabilistic occupancy grids are a common and well-proven spatial representation used in robot mapping. However, representing very large environ- ments with high resolution can still impose prohibitive memory requirements. A quadtree is a well-known data structure able to achieve compact representations of large two-dimensional binary arrays. We extend this idea and present probabilistic quadtrees for ecient representation and storage of probabilistic occupancy maps. We also discuss the implementation of probabilistic quadtrees and their integration into our robotic middleware system Miro.