12 Systems Engineering and Knowledge Modelling Flashcards
Classical vs. Systems Engineering
Classical engineering
Sequential development
Document based development
Systems engineering
Parallel development
Model-based development
Model
Representations of natural or artificial originals
Characteristics of the shortening:
Models do not capture all attributes, but only those that seem relevant to the respective modelers and/or model users.
Pragmatic characteristic
Models fulfil their replacement function
* For certain subjects
* Within certain time intervals
* With restriction to certain operations.
View and Viewpoint
View:
Exact from the perspective of specific system concerns, which bundles relevant elements and relationships
Viewpoint:
Conventions for the design, interpretation and use of views
Model-Based Systems Engineering
o Cross-disciplinary modelling of the overall system
o Stepwise derivation of the models
o Modelling language: SysML
Benefits of Systems Engineering
- Shared understanding of system requirements and design
- Assists in managing complex system development
- Improved Design Quality
- Supports early and ongoing verification and validation to reduce risk
- Enhance knowledge capture
Industrial IoT
o Connects Production Systems
o Idea of the IoT: Networking cyber-physical systems to exchange data
Potential benefits of production data
Recognize cause-effect relationships and feedback findings
Make predictions about process behavior and take appropriate measures at an early stage
Efficient use of resources through precise system knowledge and transparency
Potential benefits of production data
Recognize cause-effect relationships and feedback findings
Make predictions about process behavior and take appropriate measures at an early stage
Efficient use of resources through precise system knowledge and transparency
Linked Data
o Resources are uniquely identified with a URI (Uniform Resource Identifier)
o Data and information on Resources are available through this URI
o Resources are linked with each other via relations
Resource Description Framework (RDF)
RDF-Triplets consist of subject, predicate, object
Subject -> Resource
Predicate -> Property
Object -> Resource/literal
Semantic Technologies for Production Use Cases
Data/Service Catalog
Storing of data sources
Integrating Domains
Linking data such that it is machine- and human-interpretable
Database Access
User-friendly data query
Consistency and Reasoning
Drawing logical conclusions
Data Aggregation
Accumulation of data in order to represent complex situations
Virtual Commissioning
- Creation of virtual prototypes for a direct validation during development
o Interdisciplinary communication
o Inter-department mock-up - Shifting of software development and implementation to virtual prototypes
Potentials and Disadvantages of Virtual Commissioning
Potentials:
o Training with virtual prototypes can lead to earlier start-of-production
o Less design changes in the later phases
Disadvantages:
o Introduction of interdisciplinary engineering is complex
o Additional effort for modeling a virtual prototype
Controlling Architecture ofr Production Plants
o Heterogeneous controllers
Programmable logic controllers
Motion controller
Simple control units (e.g. limit control)
o Distributed, decentralized control of actuators and monitoring of conditions (sensors)
o Multiple operator stations (Human Machine Interfaces – HMI)
o In comparison to machine tools: Control software on individual stations generally less extensive
Controlling Architectures of Machine Tools
o Controller elements:
Numerical Controller (NC)
Programmable Logic Controller (PLC)
Additional controller (e.g. safety-PLC)
o Operational control elements:
Human Machine Interface (HMI)
Machine Control Panel (MCP)
Additional elements (e.g. for NC-Start or confirmation)
o Transfer of I/O Signals between PLC and machine bus
o Drive is connected to NC (position regulator) and PLC (status signals)
