In this article, we present results obtained from field trials with the Hobbit robotic platform, an assistive, social service robot aiming at enabling prolonged independent living of older adults in their own homes. Our main contribution lies within the detailed results on perceived safety, usability, and acceptance from field trials with autonomous robots in real homes of older users. In these field trials, we studied how 16 older adults (75 plus) lived with autonomously interacting service robots over multiple weeks. Robots have been employed for periods of months previously in home environments for older people, and some have been tested with manipulation abilities, but this is the first time a study has tested a robot in private homes that provided the combination of manipulation abilities, autonomous navigation, and non-scheduled interaction for an extended period of time. This article aims to explore how older adults interact with such a robot in their private homes. Our results show that all users interacted with Hobbit daily, rated most functions as well working, and reported that they believe that Hobbit will be part of future elderly care. We show that Hobbit’s adaptive behavior approach towards the user increasingly eased the interaction between the users and the robot. Our trials reveal the necessity to move into actual users’ homes, as only there, we encounter real-world challenges and demonstrate issues such as misinterpretation of actions during non-scripted human-robot interaction.

We propose a new hybrid method for 3D human body pose estimation based on RGBD data. We treat this as an optimization problem that is solved using a stochastic optimization technique. The solution to the optimization problem is the pose parameters of a human model that register it to the available observations. Our method can make use of any skinned, articulated human body model. However, we focus on personalized models that can be acquired easily and automatically based on existing human scanning and mesh rigging techniques. Observations consist of the 3D structure of the human (measured by the RGBD camera) and the body joints locations (computed based on a dis-criminative, CNN-based component). A series of quantitative and qualitative experiments demonstrate the accuracy and the benefits of the proposed approach. In particular, we show that the proposed approach achieves state of the art results compared to competitive methods and that the use of personalized body models improve significantly the accuracy in 3D human pose estimation.

Model-based approaches to 3D hand tracking have been shown to perform well in a wide range of scenarios. However, they require initialisation and cannot recover easily from tracking failures that occur due to fast hand motions. Data-driven approaches, on the other hand, can quickly deliver a solution, but the results often suffer from lower accuracy or missing anatomical validity compared to those obtained from model-based approaches. In this work we propose a hybrid approach for hand pose estimation from a single depth image. First, a learned regressor is employed to deliver multiple initial hypotheses for the 3D position of each hand joint. Subsequently, the kinematic parameters of a 3D hand model are found by deliberately exploiting the inherent uncertainty of the inferred joint proposals. This way, the method provides anatomically valid and accurate solutions without requiring manual initialisation or suffering from track losses. Quantitative results on several standard datasets demonstrate that the proposed method outperforms state-of-the-art representatives of the model-based, data-driven and hybrid paradigms.

In this paper, we present an efficient algorithm for synthesizing novel, arbitrarily long animations of periodic dances. The input to the proposed method is motion capture data acquired from markeless visual observations of a human performing a periodic dance. The provided human motion capture data are temporally segmented into the constituent periodic motion patterns. These are further organized in a motion graph that also represents possible transitions among them. Finally, an efficient algorithm exploits this representation to come up with a previously unseen sequence of motion patterns that are stitched seamlessly into a novel, realistic dance animation. Several experiments have been conducted with real recordings of Greek folk dances. The obtained results are very promising and indicate the efficacy of the proposed approach, as well as its tolerance to dynamic and noisy human motion capture input.

A frequent need of museums is to provide visitors with context-sensitive information about exhibits in the form of maps, or scale models. This paper suggests an augmented-reality approach for supplementing physical surfaces with digital information, through the use of pieces of plain paper that act as personal, location-aware, interactive screens. The technologies employed are presented, along with the interactive behavior of the system, which was instantiated and tested in the form of two prototype setups: a wooden table covered with a printed map and a glass case containing a scale model. The paper also discusses key issues stemming from experience and observations in the course of qualitative evaluation sessions.

This paper proposes a feature-based method for recovering the relative positions of the viewpoints of a set of panoramic images for which no a priori order information is available, along with certain structure information regarding the imaged environment. The proposed approach operates incrementally, employing the Levenshtein distance to deduce the spatial proximity of image viewpoints and thus determine the order in which images should be processed. The Levenshtein distance also provides matches between images, from which their underlying environment points can be recovered. Recovered points that are visible in multiple views permit the localization of more views which in turn allow the recovery of more points. The process repeats until all views have been localized. Periodic refinement of the reconstruction with the aid of bundle adjustment, distributes the reconstruction errors among images. The method is demonstrated on several unordered sets of panoramic images obtained in an indoor environment.