11,361 research outputs found
Evaluation of Cognitive Architectures for Cyber-Physical Production Systems
Cyber-physical production systems (CPPS) integrate physical and computational
resources due to increasingly available sensors and processing power. This
enables the usage of data, to create additional benefit, such as condition
monitoring or optimization. These capabilities can lead to cognition, such that
the system is able to adapt independently to changing circumstances by learning
from additional sensors information. Developing a reference architecture for
the design of CPPS and standardization of machines and software interfaces is
crucial to enable compatibility of data usage between different machine models
and vendors. This paper analysis existing reference architecture regarding
their cognitive abilities, based on requirements that are derived from three
different use cases. The results from the evaluation of the reference
architectures, which include two instances that stem from the field of
cognitive science, reveal a gap in the applicability of the architectures
regarding the generalizability and the level of abstraction. While reference
architectures from the field of automation are suitable to address use case
specific requirements, and do not address the general requirements, especially
w.r.t. adaptability, the examples from the field of cognitive science are well
usable to reach a high level of adaption and cognition. It is desirable to
merge advantages of both classes of architectures to address challenges in the
field of CPPS in Industrie 4.0
CUSTARD (Cranfield University Space Technology Advanced Research Demonstrator) - A Micro-System Technology Demonstrator Nanosatellite. Summary of the Group Design Project MSc in Astronautics and Space Engineering. 1999-2000, Cranfield University
CUSTARD (Cranfield University Space Technology And Research Demonstrator) was
the group design project for students of the MSc in Astronautics and Space
Engineering for the Academic Year 1999/2000 at Cranfield University. The project
involved the initial design of a nanosatellite to be used as a technology
demonstrator for microsystem technology (MST) in space. The students worked
together as one group (organised into several subgroups, e.g. system,
mechanical), with each student responsible for a set of work packages. The
nanosatellite designed had a mass of 4 kg, lifetime of 3 months in low Earth
orbit, coarse 3-axis attitude control (no orbit control), and was capable of
carrying up to 1 kg of payload. The electrical power available was 18 W (peak).
Assuming a single X-band ground station at RAL (UK), a data rate of up to 1 M
bit s-1 for about 3000 s per day is possible. The payloads proposed are a
microgravity laboratory and a formation flying experiment.
The report summarises the results of the project and includes executive
summaries from all team members. Further information and summaries of the full
reports are available from the College of Aeronautics, Cranfield University
Automatic instantiation of abstract tests on specific configurations for large critical control systems
Computer-based control systems have grown in size, complexity, distribution
and criticality. In this paper a methodology is presented to perform an
abstract testing of such large control systems in an efficient way: an abstract
test is specified directly from system functional requirements and has to be
instantiated in more test runs to cover a specific configuration, comprising
any number of control entities (sensors, actuators and logic processes). Such a
process is usually performed by hand for each installation of the control
system, requiring a considerable time effort and being an error prone
verification activity. To automate a safe passage from abstract tests, related
to the so called generic software application, to any specific installation, an
algorithm is provided, starting from a reference architecture and a state-based
behavioural model of the control software. The presented approach has been
applied to a railway interlocking system, demonstrating its feasibility and
effectiveness in several years of testing experience
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