Steffen Prüter

Web services on deeply embedded devices with real-time processing

Service-oriented architectures become more and more important in connecting devices with each other. The main advantages of service-oriented architectures are higher abstraction level and interoperability of devices. In this field Web services become the most important standard for communication between devices. But this upcoming technology is only available on powerful devices. Embedded hardware is often excluded from the deployment of Web services because of the lack of resources like computing power and memory. In this area also real-time capabilities for process control are required. This paper presents a new approach to handle Web services communication on deeply embedded hardware with the devices profile for Web services specification.

Devices Profile for Web Services in Wireless Sensor Networks: Adaptations and enhancements

For Service-oriented Architectures, Web Services are claimed as state of the art to connect business execution layers as well as networking devices. Additionally, the deployment of Wireless Sensor Networks became applicable over the last years. The usage of application layer gateways and proxy concepts allow the integration of these sensor networks into real world scenarios and existing networks that make use of Web Services. This paper presents a new approach to adapt and enhance the Devices Profile for Web Services to be applied in Wireless Sensor Networks directly. Thus, seamless connectivity between business layers, device level networks, and Wireless Sensor Networks are possible.

Devices Profile for Web Services and the REST

For future application scenarios of resource constrained and low cost smart cooperating objects, miscellaneous technologies for wireless connectivity are existing or upcoming in the near future. But further cross domain middleware and dedicated communication protocols to provide syntactic and semantic interoperability and not only technical interoperability are still missing. Thus, this paper investigates on two major candidates for IP based low power communication, based on known and matured technologies and protocols. Therefore, analyses and pitfalls of RESTful architectures based on HTTP and the Devices Profile for Web Services are presented. Furthermore, the paper discusses differences of DPWS and RESTful design and furthermore proposes an approach for a generic mapping of emerging Bluetooth Low Energy technology with RESTful device architectures for seamless and transparent connectivity.

Applicability of Web Service Technologies to Reach Real Time Capabilities

Currently the developing process for enterprise applications is improved by the service oriented architecture (SOA) paradigms. With SOAs the creation of modular and clearly defined software architectures at a high grade of interoperability and reusability is possible. For resource- constraint networked devices the devices profile for Web services (DPWS) specification adapt the SOA paradigms to create a framework for interoperable and standardized communication between embedded devices. This paper explains how special parts of DPWS can be adapted to provide real-time capabilities. So this paper shows how developers of real-time software can use the advantages of Web services and which adaptations are necessary to create Web services with real-time capabilities.

Real-time service-oriented communication protocols on resource constrained devices

Service-oriented architecture (SOA) become more and more important in connecting devices with each other. The main advantages of service-oriented architectures are a higher abstraction level and interoperability of devices. In this area, Web services have become an important standard for communication between devices. However, this upcoming technology is only available on devices with sufficient resources. Therefore, embedded devices are often excluded from the deployment of Web services due to a lack of computing power and memory. Furthermore, embedded devices often require real-time capabilities for communication, and process control. This paper presents a new table driven approach to handle real-time capable Web services communication, on embedded hardware through the devices profile for Web services.

Towards a Platform for User-Generated Mobile Services

In the near future, the trend of user-generated content and services currently observable in the Internet domain will also affect the mobile environment: mobile users will become able to easily create content and small services while on the move and offer them to social communities. Mobile users will no longer be pure consumers, they will also become producers and providers of mobile content and services. However, to let this vision come true, a new mobile service platform has to be built and established. In this article we are surveying relevant aspects, like service technologies, semantic search and recommendation mechanisms, revenue sharing, and security technologies. Based on that survey, requirements and challenges are identified. By means of an application scenario from the health and fitness domain, we present a first concept for a platform that allows for building virtual communities with easy and inherent support for real physical meetings.

Adaptation of resource-oriented service technologies for industrial informatics

In the domain of industrial automation the interoperability of devices gains importance. One major trend is the usage of Ethernet based solutions to connect devices at all levels of a company. Through a common interface technology in all levels of execution, a central control mechanism or business flows can control an entire workflow. This paper describes a new RESTful oriented device architecture, called RODA. RODA will be compared against Web services based service-oriented devices architecture. It describes how Web services technologies can be adapted to fulfill the requirements of automation, embedded, and real-time domains. The development process in these domains can gain an advantage, with the usage of middleware components based on well-known Internet technologies. Furthermore, the created interfaces can be easily reused in other applications and merged with other interfaces to combine a bundle with an additional benefit. The applicability of RODA has been verified on a mobile robotics testbed, where robots are communicating via different wireless interfaces.

Local Movement Control with Neural Networks on Autonomous Robots

In the RoboCup small-size league, the positions of the robots are commonly calculated via a camera mounted above the field and different kinds of artificial intelligence methods hosted on a PC outside the field. In this case, the robots position must be predicted because of the various time delays until the position data arrived at the robot. This paper focuses on the use of local sensors attached to the robot, and a neural network to estimate the actual robot position. This paper shows how local sensors can compensate for the effect of latency times and how the actual robot position can be estimated. Slip and friction effects that cannot be measured with local sensors can be adjusted by a neutral network, for which the implementation is adapted to the low resources available on the robot.