Klaus Schilling

Communication in Distributed Satellite Systems

The information flow between the different components of a distributed mobile sensor system is crucial in order to enable coordination for an efficient overall performance. This section provides further details for the special situation of network nodes consisting of several satellites and ground stations. Via the communication system partially autonomous functions at each satellite are to be coordinated to enable joint observations. Such self-organized activities of the space segment have to integrate with teleoperations based on supervisory control interaction from ground stations. Related suitable communication design approaches are the central topic of this chapter.

Constraints of Potential Field for Obstacle Avoidance on Car-like Mobile Robots

Abstract The well-known potential field method for obstacle avoidance in the scope of mobile robots is discussed in this paper. Particular attention is on the car-like mobile robots, which impose practical limitations on the application of potential field method due to its limited speed and curvature in motion. Along with the review of some recent studies on this topic, we point out the necessity of implementing a nonholonomic motion planner and propose some extensions to other potential-field-related methods to deal with the constraints of car-like robots. Two exemplary scenarios based on our extensions are simuated to prove their feasibility in application.

Ground Station Networks for Distributed Satellite Systems

A space mission is typically divided in space and ground segment, the focus of this chapter lies on ground station networks. Especially highly distributed ground station networks offer new opportunities for the operation of distributed satellite systems. Actual networking concepts are presented and research challenges in the field of ground station networking are discussed.

Support of power plant telemaintenance with robots by Augmented Reality methods

In power plants, in many cases direct human access to crucial sites for inspection or maintenance is impossible. Here, remotely operated robots offer good potential to handle these tasks. This relates to technology challenges for remote operations. In this contribution we propose the use of an Augmented Reality interface as a means to directly and intuitively visualize complex information to overcome some of the challenges and support the teleoperator in his duties. Support functions that could be employed for several tasks in the context of inspection or maintenance are introduced.

Advanced Techniques for Spacecraft Motion Estimation Using PMD Sensors

Abstract Several machine vision based techniques have been developed in the past to estimate relative motions and pose among spacecrafts and to assist them in Rendezvous and Docking maneuvers. These techniques have typically relied on stereo vision for range information and image processing techniques primarily for object and pattern recognition and their tracking among the others. Development of state-of-the-art 3D imaging sensors such as PMD sensor based cameras opened up possibilities for new and innovative techniques in the field of machine vision. This paper presents an innovative approach for estimating the relative position and pose of a spacecraft by combining the strengths of a proven edge detection algorithm with the advantages of using a 3D imager in real-time machine vision applications.

Control of a HexaPOD treatment couch for robot-assisted radiotherapy.

Abstract Moving tumors, for example in the vicinity of the lungs, pose a challenging problem in radiotherapy, as healthy tissue should not be irradiated. Apart from gating approaches, one standard method is to irradiate the complete volume within which a tumor moves plus a safety margin containing a considerable volume of healthy tissue. This work deals with a system for tumor motion compensation using the HexaPOD® robotic treatment couch (Medical Intelligence GmbH, Schwabmünchen, Germany). The HexaPOD, carrying the patient during treatment, is instructed to perform translational movements such that the tumor motion, from the beams-eye view of the linear accelerator, is eliminated. The dynamics of the HexaPOD are characterized by time delays, saturations, and other non-linearities that make the design of control a challenging task. The focus of this work lies on two control methods for the HexaPOD that can be used for reference tracking. The first method uses a model predictive controller based on a model gained through system identification methods, and the second method uses a position control scheme useful for reference tracking. We compared the tracking performance of both methods in various experiments with real hardware using ideal reference trajectories, prerecorded patient trajectories, and human volunteers whose breathing motion was compensated by the system.

Evaluation of a Drive Assistance Function for Older Adults

Abstract Assistive technologies for older adults are getting more and more attention because of changes in demographics. Mobility is one of the biggest issues for people with degenerating physical and mental abilities, such that they are able to live independently. Therefore, this paper deals with the development and the evaluation of a drive assistance function for a mobility scooter to help keep older people mobile. The implemented drive assistance function reduces the challenging control of the vehicle and provides supports for the operator. The assistance function analyses the driving commands of the operator and controls the mobility scooter according to these commands. Finally, an evaluation of the assistance function with odler people shows the less challenging control and the increased safety.

SpaceMaster: Master in Space Science and Technology As an International Interdisciplinary Educational Effort

Abstract Aerospace engineers are very demanded, as there are only small numbers of well-trained specialists in this field available. In response, 2005 the international curriculum “SpaceMaster” was established in the European elite-program “Erasmus Mundus” to train talented young people in the challenging subject of space science and technology. Here six European universities cooperate and contribute their special expertise to this interdisciplinary curriculum. In particular system design techniques are emphasized, which are of interest for a broad spectrum of industrial applications extending well beyond aerospace. Emphasis is placed on realization aspects in practicals, including especially contributions to the University Wurzburgs pico-satellite program in the framework of thesis work. So far the two satellites UWE-1 and -2 have been successfully placed in orbit, but a roadmap towards formation flying offers long-term perspectives for future UWE missions. In this contribution the international university cooperation, the curriculum and the specific aspects of pico-satellite realizations are addressed, in particular with respect to attitude determination/control aspects.

Setting up a surveillance system in the civil domain with cooperating UAVs and UGVs

Abstract This work gives an overview of the project SiNafaR, safe navigation for autonomous robot systems, which aims at identifying requirements, legal aspects in Germany, and finding technological solutions for heterogeneous multi robotic systems in the civil sector. Based on a security services scenario a surveillance system consisting of UAVs and UGVs is proposed. Main technological gaps, such as assessable localization, reliable communication and consistent HMI are identified and solutions are presented.