Systems engineering

Systems engineering techniques are used in complex development projects

Systems engineering (also system engineering , systems design or systems design engineering ) is an interdisciplinary approachto develop and implementcomplex technical systems in large projects . Systems engineering is necessary because, especially in large, complex projects, issues such as logistics and coordination are more difficult to handle and can lead to massive problems in the implementation of the project. Basic systems engineering processes are documented in the ISO / IEC / IEEE-15288 Systems and Software Engineering standard.

overview

The focus of systems engineering is on fulfilling the customer's desired requirements for the system to be delivered, which are contained in the specification , within the cost and time frame by

the system is broken down and specified into subsystems, devices and software and
the implementation is continuously monitored across all levels up to the handover to the customer.

In particular, the entire problem ( operation , costs , schedule , performance , training and support , test , production and recycling ) should be taken into account.

Systems engineering integrates all of these engineering disciplines and skills into a uniform, team-oriented structured process which, depending on the complexity of the system, can extend over several levels up to a device of a subcontractor. This process is applied from conception to production to operation and in some cases to dismantling or recycling.

Systems Engineering ideally takes into account the technical, economic and social needs of all customers with the aim of handing over a product to the customer that corresponds to their ideas. One task is therefore to determine the limits for the costs, schedule and producibility and to ensure compliance with them through continuous risk assessment and minimization.

Systems engineering is based on the fact that a system is more than the sum of its subsystems (or parts) and for this reason the overall interrelationships must be considered. In the case of a complex system, the responsible system engineer uses a team of other system engineers who take on responsibility for different areas.

Systems engineering has become a synonym in English-speaking countries for the development of the entire product ( hardware , software , service ) and the additional systems required (for example the test system or the machine used to manufacture the product). This role was recently supplemented by human-computer interaction (MCI) and recycling.

The systems engineer is required because, for example, a hardware engineer deals (more or less) with the hardware and a software engineer (more or less) with the software and they therefore have little time or lack the qualifications to deal intensively with the optimized runnability of the software on the hardware or that the whole system with its elements interacts as well as possible with its environment, especially the user, or whether it can be used as planned. With comprehensive systems - such as the development of Columbus (room laboratory) - a large number of disciplines must be coordinated (thermodynamics, ergonomics, etc.) in order to optimize the overall system.

Methods and tasks

Methods and tasks of systems engineering are

Definition and planning of systems engineering tasks and progress assessment for reporting to project management ;
Requirements analysis , requirements definition and requirements management , the basis of system development;
System design optimization ( modeling , simulation and evaluation ), the development of the system;
System documentation (functional descriptions, drawings, manuals, etc.);
Configuration control / change management , in development there are often changes that have to be entered in all documents in a comprehensible manner up to the production drawing;
System integration ( interfaces - Specification - or product development ; to ensure perfect integration into the next larger system)
System verification and validation to ensure that requirements have been met;
Risk management through periodic target / actual comparisons for critical parameters (mass, electrical power, software / program runtime / size, etc.);
Product and quality assurance (e.g. fault trees , fault analysis, FMEA );
Sustainable development , every system should be developed sustainably.

Depending on the complexity and project phase of the system to be developed, the main tasks and content are different.

history

The first significant use of "Systems Engineering" took place in 1940 at Bell Laboratories in telephony . The different parts of the telecommunications system had to and must interact very well, which was only possible through a comprehensive understanding of the system and precise specification of the requirements.

After the Second World War , “Systems Engineering” became stronger in American space travel a. a. used in the Apollo program and in the development of the space shuttle . The systems engineering approach has been continuously developed by NASA.

It was used intensively in European space travel after the failure of the Europa rockets . The failures occurred because the various levels were developed without joint coordination and they were therefore not coordinated with one another. Therefore, systems engineering was used extensively by the French in the development of the Ariane rocket , which ultimately led to a great success of the rocket. Since then, it has been standard in space travel to employ system engineers.

In general, systems engineering is used to various degrees in almost all companies , although in some cases it only has other names. The extreme effort for verification , which drives up the costs of space programs, is only implemented to a lesser extent in commercial companies.

scope

In industry, new developments are becoming more and more complex, as customer requirements keep increasing. In order to make these interdisciplinary developments possible at all in an acceptable time, it is important to keep track of things. Systems engineering was developed precisely for this purpose. It is important that the development of large and small systems can lead to new system information and that this information must not be lost for later developments.

Decisions at the beginning of a project, the effects of which are not fully understood, can lead to huge effects at the end of the project, and it is up to the modern systems engineer to find those effects and make critical decisions. There is and there will be no method which guarantees that a decision made today is still valid when a system is in maintenance after years or decades, but there are techniques to support the process of "systems engineering". Examples of the use of simple system methodologies are Jay Wright Forrester's " System Dynamics " methods and the Unified Modeling Language (UML), which are constantly being developed to support the development process. Modeling and simulation of the system, as is now common in all industries and sciences, is helpful in order to detect errors and risks before production.

Areas related to systems engineering

It is obvious that many special areas or niches within engineering come into contact with the sub-areas of systems engineering. The increasing number of complex and very different systems creates ever greater overlap between these areas. Many sub-areas understand their own services only as part of the larger areas, but they also contribute to the further development and research of systems engineering.

Software development

Software development has recently helped to further develop systems engineering. Techniques that were originally developed to deal with complex software-intensive systems have helped to implement major changes in the tools, methods and processes used in systems engineering, for example SysML , CMMI , object-oriented analysis and design, requirements management , formal Methods and Formal Languages .

Security technology

Today safety technology is used wherever people want to secure large complex events so that these systems cannot cause damage. Most of these security techniques are used to deal with errors in a planned manner.

The current development standards define risk categories and models for security levels or security requirement levels and derive requirements for development and quality assurance from them. Another area is the fault tree analysis (FTA), which is to be continued on the software, despite the complexity of the software, a possible goal in the development of systems engineering.

Reliability engineering

Reliability engineering is a discipline to ensure that a system meets user expectations or that it is free from defects during the product life. Reliability engineering is used for the entire system with its hardware and software. It is strongly linked to maintainability and logistics. Reliability engineering is often used with sub-areas of safety engineering, such as failure behavior and fault trees. Reliability engineering relies heavily on statistics, probability theory and operational safety theory with its tools and processes.

Interface design

Interface design is concerned with connecting the parts of a system together. So z. B. Communication protocols are determined to ensure the interactions of the systems or subsystems.

An example of this is that signals that leave a system should, for example, be within a tolerance or that the receiver should have a greater signal tolerance than the transmitter in order to keep the system sufficiently stable.

Human-computer interaction ( English human-computer interaction , HCI) is another aspect of the interface design and a very vital part of modern systems engineering when to the user of a system is considered.

It should also be noted that each system is also a subsystem of another. A pump manufacturer, for example, should therefore think about how its customer wants to use the pump and design the interfaces accordingly.

"Every system is somebody's subsystem."

"Every system is someone's subsystem"

Cognitive "Systems Engineering"

Cognitive “systems engineering” sees people as part of the system. Cognitive systems engineering is closely related to the experience gained over decades in the applications of the two sub-areas of cognitive psychology and systems engineering. Cognitive systems engineering has focused strongly on researching the interactions between humans and the environment, and systems are also to be developed that integrate human thinking. Cognitive systems engineering works on the points:

Problems caused by the environment
Need for intermediaries (human and software)
Interaction of the different systems and technologies in order to be able to influence the situation.

Risk management

Risk management is a necessary tool in systems engineering, so that possible dangers of developments can be assessed and thus the system development can be carried out successfully. It can thus be avoided, for example, that the effects of individual subsystems lead to a crash of the entire system.

Example of a systems engineering process

In order to be able to describe the whole system, it is important to find consistent methods for development and analysis at the system and software level. One possibility is to use SysML , which was developed on the basis of UML in order to be able to develop and control complex systems. In part, this modeling language has already been integrated in development software (e.g. ARTiSAN Studio from ARTiSAN , Enterprise Architect from SparxSystems, Rhapsody from Telelogic , Papyrus 4 SysML Freeware). If the customer's requirements with software tools (e.g. DOORS and RequisitePro from IBM Rational , IRQA from Visure Solutions, Caliber-RM from Borland , CARE from Sophist Group, in-Step from microTOOL) are also integrated into this development process, this ensures a high degree of traceability of the decisions made in development.

Study and training

In Germany there are more and more universities and now also a few universities that offer systems engineering as a face-to-face or distance learning course. At the university's internal institute for scientific further education (casc - campus advanced studies center) of the University of the Federal Armed Forces Munich, for example, a further education Master’s degree in Systems Engineering (M.Sc.) is offered. Employees with a first professional university degree are prepared for complex management and leadership tasks in the armed forces, public service, business and industry as part of the application-related further education offer in the future field of systems engineering. The course is interdisciplinary. The focus is on a holistic and systematic approach and procedure as well as the consistent use of methods and processes of systems engineering. The students receive the necessary tools to structure, analyze, specify, develop and adapt complex systems with their various requirements over the entire system life cycle. In addition to the master’s course, only individual university certificates can be acquired in the so-called module course. These can then be credited towards the master’s degree. The in-service training takes place in the blended learning format, i. H. Distance learning phases alternate with attendance phases on campus.

However, since systems engineering can be interpreted broadly as a term, training can be designed differently from training institution to training institution and, in particular, can also set different priorities. For example, the Ulm University of Applied Sciences offers a master's degree in "Systems Engineering and Management" with a focus on electrical engineering, mechanical engineering, industrial management and logistics, whereby the focus on electrical engineering can also be completed with an international exchange and thus in English.

In Switzerland, systems engineering is mainly taught as a compulsory subject at the ETH Zurich , for example in the courses of study in the Department of Civil, Environmental and Geomatic Engineering (civil, environmental and geomatic engineering).

Certification

Since 2012, the Gesellschaft für Systems Engineering eV (GfSE), in cooperation with TÜV Rheinland as an accredited certification body, has offered part-time personnel certification for systems engineers as "Certified Systems Engineer (GfSE)". The certification offers the three certification levels C (“Understand”), B (“Apply”) and A (“Master”), where A represents the expert level.

SE-Cert (GfSE)	INCOSE equivalent
Level C - understand	ASEP
Level B - apply	CSEP
Level A - master	ESEP

Level C lasts five months, includes around twelve days of attendance with a licensed training provider and ends with a two-hour examination by TÜV Rheinland and GfSE assessors . The awarded certificate represents independent evidence of knowledge in systems engineering.

Holders of the SE certificates level C and B can apply for the corresponding INCOSE certificate.

literature

WF Daenzer, F. Huber: Systems Engineering. Methodology and practice . 11th edition. Industrielle Organization Verlag, Zurich 1999, ISBN 978-3-85743-998-8 .
John C. Ballamy: Digital Telephony . Telecommunications and Signal Processing. Wiley Series, 2000, ISBN 0-471-34571-7 .
Rainer Züst: Entry into systems engineering, in a nutshell . 3. Edition. 2004, ISBN 978-3-85743-721-2 .
Reinhard Haberfellner , Olivier L. de Weck, Ernst Fricke, Siegfried Vössner: Systems Engineering . 12th edition. Orell Füssli, Zurich 2012, ISBN 978-3-280-04068-3 .
Tim Weilkiens: Systems Engineering with SysML / UML . Morgan Kaufmann Publishers Inc, 2008, ISBN 0-12-374274-9 .
Oliver Alt: Model-based system development with SysML . Hanser Verlag, Munich 2012, ISBN 978-3-446-43066-2 .