This PhD work was partially supported by the European LIREC project (Living with robots and interactive companions) a collaboration of 10 EU partners that aims to develop a new generation of interactive and emotionally intelligent companions able of establishing and maintaining long-term relationships with humans. The project takes a multi-disciplinary approach towards investigating methods to allow robotic companions to perceive, remember and react to people in order to enhance the companion’s awareness of sociability in domestic environments. (e.g. remind a user and provide useful information, carry heavy objects etc.). One of the project's scenarios concerns remote human-human communication enhancement utilising autonomous robots as social mediators which is the focus of this PhD thesis. This scenario involves a remote communication situation between two distant users who wish to utilise their robot companions in order to enhance their communication and interaction experience with each other over the internet. The scenario derived from the need of communication between people who are separated from their relatives and friends due to work commitments or other personal obligations. Even for people that live close by, communication mediated by modern technologies has become widespread. However, even with the use of video communication, they are still missing an important medium of interaction that has received much less attention over the past years, which is touch. The purpose of this thesis was to develop autonomous robots as social mediators in a remote human-human communication scenario in order to allow the users to use touch and other modalities on the robots. This thesis addressed the following research questions: Can an autonomous robot be a social mediator in human-human remote communication? How does an autonomous robotic mediator compare to a conventional computer interface in facilitating users’ remote communication? Which methodology should be used for qualitative and quantitative measurements for local user-robot and user-user social remote interactions? In order to answer these questions, three different communications platforms were developed during this research and each one addressed a number of research questions. The first platform (AIBOcom) allowed two distant users to collaborate in a virtual environment by utilising their autonomous robotic companions during their communication. Two pet-like robots, which interact individually with two remotely communicating users, allowed the users to play an interactive game cooperatively. The study tested two experimental conditions, characterised by two different modes of synchronisation between the robots that were located locally with each user. In one mode the robots incrementally affected each other’s behaviour, while in the other mode, the robots mirrored each other’s behaviour. This study aimed to identify users’ preferences for robot mediated human-human interactions in these two modes, as well as investigating users’ overall acceptance of such communication media. Findings indicated that users preferred the mirroring mode and that in this pilot study robot assisted remote communication was considered desirable and acceptable to the users. The second platform (AiBone) explored the effects of an autonomous robot on human-human remote communication and studied participants' preferences in comparison with a communication system not involving robots. We developed a platform for remote human-human communication in the context of a collaborative computer game. The exploratory study involved twenty pairs of participants who communicated using video conference software. Participants expressed more social cues and sharing of their game experiences with each other when using the robot. However, analysis of the interactions of the participants with each other and with the robot show that it is difficult for participants to familiarise themselves quickly with the robot while they can perform the same task more efficiently with conventional devices. Finally, our third platform (AIBOStory) was based on a remote interactive story telling software that allowed users to create and share common stories through an integrated, autonomous robot companion acting as a social mediator between two people. The behaviour of the robot was inspired by dog behaviour and used a simple computational memory model. An initial pilot study evaluated the proposed system's use and acceptance by the users. Five pairs of participants were exposed to the system, with the robot acting as a social mediator, and the results suggested an overall positive acceptance response. The main study involved long-term interactions of 20 participants in order to compare their preferences between two modes: using the game enhanced with an autonomous robot and a non-robot mode. The data was analysed using quantitative and qualitative techniques to measure user preference and Human-Robot Interaction. The statistical analysis suggests user preferences towards the robot mode. Furthermore, results indicate that users utilised the memory feature, which was an integral part of the robot’s control architecture, increasingly more as the sessions progressed. Results derived from the three main studies supported our argument that domestic robots could be used as social mediators in remote human-human communications and offered an enhanced experience during their interactions with both robots and each other. Additionally, it was found that the presence of intelligent robots in the communication can increase the number of exhibited social cues between the users and are more preferable compared to conventional interactive devices such as computer keyboard and mouse.

Using physical analogies when solving computational problems is not uncommon. The Electric Field Approach is such an analogy using potential fields for describing the situation in a robotic soccer match and for proposing the next step in optimizing the situation. The approach was developed and implemented during the summer of 2000 and was later used and tested during the fourth Robot Soccer World Cup in Melbourne, Australia. The results of the games prove that the approach is applicable in this narrow but interesting domain, combining artificial intelligence and robotics. The theory of the approach is general and can also be applied on various other domains. This is not the first potential field approach, but the ability of both handling navigation and manipulation of the environment is unique.

With the advent of the modern technological age, a plethora of electronic tools and devices are available in numbers as never before. While beneficial and ex-ceedingly useful, these electronic devices require users to operate them. When designing systems capable of observing and acting upon an environment, the number of devices can become unmanageable. Previously, middleware sys-tems were designed for large-scale computational systems. However, by apply-ing similar concepts and distributing logic to autonomous agents residing on the devices, a new paradigm in distributed systems research on lightweight de-vices is conceivable. Therefore, this research focuses upon the development of a lightweight middleware that can reside on small devices enabling the capabil-ity for these devices to act autonomously. In this research, analyses determined the most advantageous methods for solving this problem. Defining a set of requirements for the necessary middle-ware as well as assumptions for the environment and system in which it would operate achieved a proper research focus. By utilizing concepts already in ex-istence such as peer-to-peer networking and distributed hash tables, devices in this system could communicate effectively and efficiently. Furthermore, creat-ing custom algorithms for communicating with other devices, and collaborating on task assignments achieved an approach to solving the consensus problem in real time. The resulting middleware solution allowed a demonstration to prove the effi-cacy. Using three devices capable of observing the environment and acting up-on it, two tests highlighted the capabilities of the consensus-finding mechanism as well as the ability of the devices to respond to changes in the environment autonomously.

Thesis (doctoral)--Universität, Frankfurt am Main, 2006. / Includes bibliographical references and register.