Robotic companions for older people: a case study in the wild. - In: Annual review of cybertherapy and telemedicine 2015, (2015), S. 147-152
http://dx.doi.org/10.3233/978-1-61499-595-1-147
"Go ahead, please": recognition and resolution of conflict situations in narrow passages for polite mobile robot navigation. - In: Social Robotics, (2015), S. 643-653
For a mobile assistive robot operating in a human-populated environment, a polite navigation is an important requirement for the social acceptance. When operating in a confined environment, narrow passages can lead to deadlock situations with persons. In our approach we distinguish two types of deadlock situations at narrow passages, in which the robot lets the conflicting person pass, and either waits in a non-disturbing waiting position, or forms a queue with that person. Forthcoming deadlock situations are captured by a set of qualitative features. As part of these features, we detect narrow passages with a raycasting approach and predict the movement of persons. In contrast to numerical features, the qualitative description forms a more compact human-understandable space allowing to employ a rule-based decision tree to classify the considered situation types. To determine a non-disturbing waiting position, a multi-criteria optimization approach is used together with the Particle Swarm Optimization as solver. In field tests, we evaluated our approach for deadlock recognition in a hospital environment with narrow corridors.
http://dx.doi.org/10.1007/978-3-319-25554-5_64
Robot companion for domestic health assistance: implementation, test and case study under everyday conditions in private apartments. - In: 2015 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), (2015), S. 5992-5999
This paper presents the implementation and evaluation results of the German research project SERROGA (2012 till mid 2015), which aimed at developing a robot companion for domestic health assistance for older people that helps keeping them physically and mentally fit to remain living independently in their own homes for as long as possible. The paper gives an overview of the developed companion robot, its system architecture, and essential skills, behaviors, and services required for a robotic health assistant. Moreover, it presents a new approach allowing a quantitative description and assessment of the navigation complexity of apartments to make them objectively comparable for function tests under real-life conditions. Based on this approach, the results of function tests executed in 12 apartments of project staff and seniors are described. Furthermore, the paper presents findings of a case study conducted with nine seniors (aged 68-92) in their own homes, investigating both instrumental and social-emotional functions of a robotic health assistant. The robot accompanied the seniors in their homes for up to three days assisting with tasks of their daily schedule and health care, without any supervising person being present on-site. Results revealed that the seniors appreciated the robot's health-related instrumental functions and even built emotional bonds with it.
http://dx.doi.org/10.1109/IROS.2015.7354230
User recognition for guiding and following people with a mobile robot in a clinical environment. - In: 2015 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), (2015), S. 3600-3607
Rehabilitative follow-up care is important for stroke patients to regain their motor and cognitive skills. We aim to develop a robotic rehabilitation assistant for walking exercises in late stages of rehabilitation. The robotic rehab assistant is to accompany inpatients during their self-training, practicing both mobility and spatial orientation skills. To hold contact to the patient, even after temporally full occlusions, robust user re-identification is essential. Therefore, we implemented a person re-identification module that continuously re-identifies the patient, using only few amount of the robot's processing resources. It is robust to varying illumination and occlusions. State-of-the-art performance is confirmed on a standard benchmark dataset, as well as on a recorded scenario-specific dataset. Additionally, the benefit of using a visual re-identification component is verified by live-tests with the robot in a stroke rehab clinic.
http://dx.doi.org/10.1109/IROS.2015.7353880
IRON: a fast interest point descriptor for robust NDT-map matching and its application to robot localization. - In: 2015 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), (2015), S. 3144-3151
This work introduces the IRON keypoint detector and the IRON descriptor which enable high-speed and high-accuracy alignment of 3D depth maps. Instead of using raw point values for storing 3D-scenes, all algorithms were designed to operate on Normal Distribution Transforms (NDT), since NDT-maps provide a highly memory-efficient representation of depth data. By taking into account surface curvature and object shape within NDT-maps, patches with strong surface variability can be recognized and described precisely. In this paper, the whole feature extraction process, as well as descriptor matching, outlier detection, and the final transform calculation between NDT-maps is elaborated. The presented technique is particularly insensitive to an initial offset between both maps, has a high robustness, and it achieves more than 75 NDT-map alignments per second (including complete memory allocation each time as well) in two large publicly available depth datasets while using only a single core of a modern Intel i7 CPU. Even though the main focus of this work was placed on the proposed IRON registration algorithm, two specific applications of this NDT-matching approach are outlined in the second part, namely robot pose tracking and NDT-one-shot localization within densely furnished domestic environments.
http://dx.doi.org/10.1109/IROS.2015.7353812
R2D2 reloaded: dynamic video projection on a mobile service robot. - In: 2015 European Conference on Mobile Robots, ISBN 978-1-4673-9163-4, (2015), insges. 6 S.
In this paper, we present a holistic approach to enable mobile robots using video projection in a situation aware and dynamic way. Therefore, we show how to autonomously detect wall segments that are suitable to be used as projection target in a dynamic environment. We derive several quality measures to score the wall segments found in the local environment and show how these scores can be used by a particle swarm optimization to find the best local projection position for the mobile robot. Furthermore, it is demonstrated how the presented approach can be used to display directions in an orientation training task for stroke patients while the robot is following them.
http://dx.doi.org/10.1109/ECMR.2015.7324177
Evaluation of multi feature fusion at score-level for appearance-based person re-identification. - In: International Joint Conference on Neural Networks (IJCNN), 2015, ISBN 978-1-4799-1961-1, (2015), insges. 8 S.
Robust appearance-based person re-identification can only be achieved by combining multiple diverse features describing the subject. Since individual features perform different, it is not trivial to combine them. Often this problem is bypassed by concatenating all feature vectors and learning a distance metric for the combined feature vector. However, to perform well, metric learning approaches need many training samples which are not available in most real-world applications. In contrast, in our approach we perform score-level fusion to combine the matching scores of different features. To evaluate which score-level fusion techniques perform best for appearance-based person re-identification, we examine several score normalization and feature weighting approaches employing the the widely used and very challenging VIPeR dataset. Experiments show that in fusing a large ensemble of features, the proposed score-level fusion approach outperforms linear metric learning approaches which fuse at feature-level. Furthermore, a combination of linear metric learning and score-level fusion even outperforms the currently best non-linear kernel-based metric learning approaches, regarding both accuracy and computation time.
http://dx.doi.org/10.1109/IJCNN.2015.7280360
Smart fur tactile sensor for a socially assistive mobile robot. - In: Intelligent Robotics and Applications, (2015), S. 49-60
Close natural interaction is assumed to be a key feature for a socially assistive service robot, if the user is expected to develop an emotional bond to the robot system and accept it as a companion over a prolonged period. One particularly intuitive way of affective interaction, seen e.g. between people and pets, is physical touch in the form of stroking or smacking. In order to support the companion robot's role of an intelligent pet-like buddy, we aim to equip the robot with the capabilities to recognize such physical interaction behavior and react accordingly. In this paper, we present a low cost smart fur sensor which encourages tactile interaction by the user and recognizes different touch patterns relating to various kinds of emotional expressions. Special emphasis is put on the simple and robust classification of touch patterns emerging from such tactile interaction to distinguish the respective inputs for the robot.
http://dx.doi.org/10.1007/978-3-319-22876-1_5
Universal usage of a video projector on a mobile guide robot. - In: Intelligent Robotics and Applications, (2015), S. 25-36
In this paper, we present a holistic approach to enable mobile robots using video projection in a situation aware and dynamic way. Therefore, we show how to autonomously detect wall segments that are suitable to be used as projection target in a dynamic environment. We derive several quality measures to score the wall segments found in the local environment and show how these scores can be used by a particle swarm optimization to find the best local projection position for the mobile robot.
http://dx.doi.org/10.1007/978-3-319-22873-0_3
Robotischer Reha-Assistent zum Lauftraining von Patienten nach Schlaganfall: erste Ergebnisse zum Laufcoach. - In: 8. AAL-Kongress, (2015), S. 436-445
In diesem Beitrag werden erste Ergebnisse zum Einsatz eines robotischen Reha-Assistenten als Laufcoach in einer Klinik vorgestellt. Zunächst wird das mit Laufcoach bezeichnete Einsatzszenario beschrieben und die zur Umsetzung dieses Szenarios grundlegenden Roboterverhalten sowie die eingesetzten realwelttauglichen Erkennungs-, Navigations- und Interaktionsleistungen zusammen mit der Roboterplattform vorgestellt. Die Herangehensweise an zunächst 4-tägige Funktionstests in der Klinik mit 15.000 m gefahrener Wegstrecke wird dargelegt und erste erreichte Ergebnisse zu den Roboterverhalten der autonomen und höflichen Zielanfahrt, des Lotsens und Folgens einer Person diskutiert.