System Engineering Approach to Development of an End-to-End Space Cargo Handling System

This paper, prepared for the Eighth Space Congress, was developed to illustrate how system engineering techniques were applied in the early conceptual development of an end-to-end (total system, source to user) Space Shuttle Cargo Handling System. The techniques described were applied to a study under contract to NASA, Kennedy Space Center. The paper further shows that continuation of the system engineering practices on subsequent phases of the cargo handling system development will greatly enhance the orderly and timely progression of the system through the conceptual phase into the definition, production, and operational phases. The techniques involved an orderly top-down iterative methodology following the basic guidelines of a uniquely simple system engineering diagram successfully used in the past on complete weapon systems. Methods are shown where streamlined techniques were developed to keep within the confines of calendar time limitations of the initial study and to reduce the magnitude of documentation. While system engineering is more often used for development of a system containing a major prime vehicle end item such as a weapon or an aerospace vehicle, the techniques are readily applied to a system (cargo handling system) where no single end item is dominant, but the system interfaces heavily with several major aerospace vehicles in the forthcoming space program. The conceptual definition of such interfacing aerospace vehicles as the Earth Orbiting Shuttle and the Space Station in fact become part of the baseline inputs to the system engineering progress involving the cargo handling system conceptual development. The cargo handling system is visualized as a total distribution system when treated in an end-to-end fashion

Supporting End-User Development through a New Composition Model: An Empirical Study

End-user development (EUD) is much hyped, and its impact has outstripped even the most optimistic forecasts. Even so, the vision of end users programming their own solutions has not yet materialized. This will continue to be so unless we in both industry and the research community set ourselves the ambitious challenge of devising end to end an end-user application development model for developing a new age of EUD tools. We have embarked on this venture, and this paper presents the main insights and outcomes of our research and development efforts as part of a number of successful EU research projects. Our proposal not only aims to reshape software engineering to meet the needs of EUD but also to refashion its components as solution building blocks instead of programs and software developments. This way, end users will really be empowered to build solutions based on artefacts akin to their expertise and understanding of ideal solution

The Importance Of End-User Analysis In New Information System Adapters: Lessons Learned From Practice

The implementation of Information System (IS) in new-IS adapters can remain unused even when they developed properly. The previous research shows that the unsuccessful IS utilization problem primarily related to behavioral issues rather than technical issues. The behavioral issues should be addressed in the stakeholder analysis, an activity in the inception phase of requirement engineering. End-users of an IS are one of the focuses in stakeholder analysis. We studied the correlation of the end-user analysis in new-IS adapters with the successfulness of IS utilization. We conducted a qualitative studied on 20 IS development projects. The findings show strong correlation of the end-user behavior and the IS adoption. We suggest the end-user analysis is necessary for the IS development project in new-IS adapters. We concluded that it is recommended to formally get the end-user commitment before starting the IS development process. Keyword : Information System, end-user analysis, new-IS adapters, end-user commitmen

The end-to-end testbed of the Optical Metrology System on-board LISA Pathfinder

LISA Pathfinder is a technology demonstration mission for the Laser Interferometer Space Antenna (LISA). The main experiment on-board LISA Pathfinder is the so-called LISA Technology Package (LTP) which has the aim to measure the differential acceleration between two free-falling test masses with an accuracy of 3x10^(-14) ms^(-2)/sqrt[Hz] between 1 mHz and 30 mHz. This measurement is performed interferometrically by the Optical Metrology System (OMS) on-board LISA Pathfinder. In this paper we present the development of an experimental end-to-end testbed of the entire OMS. It includes the interferometer and its sub-units, the interferometer back-end which is a phasemeter and the processing of the phasemeter output data. Furthermore, 3-axes piezo actuated mirrors are used instead of the free-falling test masses for the characterisation of the dynamic behaviour of the system and some parts of the Drag-free and Attitude Control System (DFACS) which controls the test masses and the satellite. The end-to-end testbed includes all parts of the LTP that can reasonably be tested on earth without free-falling test masses. At its present status it consists mainly of breadboard components. Some of those have already been replaced by Engineering Models of the LTP experiment. In the next steps, further Engineering Models and Flight Models will also be inserted in this testbed and tested against well characterised breadboard components. The presented testbed is an important reference for the unit tests and can also be used for validation of the on-board experiment during the mission

Model-Driven Development for End-Users, too!?

Elicitating the requirements and creating a model of a software system are standard activities in the development process of professional software development. The talk discusses whether these two development phases are also present in end-user software development and how they could look like. It is argued that one has to distinguish between at least two types of end-user software developers. Those, who are not professional software developers, but work in an engineering domain and follow stepwise development processes. They are used to have requirements specifications as well as models, too. But, non-professional, non-engineering end-users, e.g. spreadsheet developers, don\u27t and would not like to distinguish between different steps in the development process. Therefore, we propose to hide the distinction between these different steps by closely interconnecting requirements specification, models and code, and by putting them into one development box. By offering appropriate interface functions like create, adapt, refine, etc. to the box, the end-user is supported in developing software without being aware that he is undergoing a stepwise refinement process from requirements specifications towards concrete code

Historical development of the windmill

Throughout history, windmill technology represented the highest levels of development in those technical fields now referred to as mechanical engineering, civil engineering, and aerodynamics. Key stages are described in the technical development of windmills as prime movers; from antiquity to construction of the well known Smith-Putnam wind turbine generator of the 1940's, which laid the foundation for modern wind turbines. Subjects covered are windmills in ancient times; the vertical axis Persian windmill; the horizontal axis European windmill (including both post mills and tower mills); technology improvements in sails, controls, and analysis; the American farm windmill; the transition from windmills to wind turbines for generating electricity at the end of the 19th century; and wind turbine development in the first half of the 20th century

Developing a MovieBrowser for supporting analysis and browsing of movie content

There is a growing awareness of the importance of system evaluation directly with end-users in realistic environments, and as a result some novel applications have been deployed to the real world and evaluated in trial contexts. While this is certainly a desirable trend to relate a technical system to a real user-oriented perspective, most of these efforts do not involve end-user participation right from the start of the development, but only after deploying it. In this paper we describe our research in designing, deploying and assessing the impact of a web-based tool that incorporates multimedia techniques to support movie analysis and browsing for students of film studies. From the very start and throughout the development we utilize methodologies from usability engineering in order to feed in end-user needs and thus tailoring the underlying technical system to those needs. Starting by capturing real users’ current practices and matching them to the available technical elements of the system, we deployed an initial version of our system to University classes for a semester during which we obtained an extensive amount of rich usage data. We describe the process and some of the findings from this trial

Sustainable development as a meta-context for engineering education

At the end of the first decade of the twenty-first century, there is unprecedented awareness of the need for a transformation in development, to meet the needs of the present while also preserving the ability of future generations to meet their own needs. However, within engineering, educators still tend to regard such development as an ‘aspect’ of engineering rather than an overarching meta-context, with ad hoc and highly variable references to topics. Furthermore, within a milieu of interpretations there can appear to be conflicting needs for achieving sustainable development, which can be confusing for students and educators alike. Different articulations of sustainable development can create dilemmas around conflicting needs for designers and researchers, at the level of specific designs and (sub-) disciplinary analysis. Hence sustainability issues need to be addressed at a meta-level using a whole of system approach, so that decisions regarding these dilemmas can be made. With this appreciation, and in light of curriculum renewal challenges that also exist in engineering education, this paper considers how educators might take the next step to move from sustainable development being an interesting ‘aspect’ of the curriculum, to sustainable development as a meta-context for curriculum renewal. It is concluded that capacity building for such strategic considerations is critical in engineering education

Some problems of professional end user developers

By the term 'professional end user developers' we mean people such as research scientists who work in highly technical, knowledge-rich domains and who develop software in order to further their professional goals. In common with other end user developers, professional end user developers do not describe themselves as software engineers and have no formal training in software engineering. They differ from most other end user developers, however, in that learning programming languages rarely presents them with any problem. In this paper, drawing on data from field studies of different groups of professional end users, we examine the problems that such people face in meeting the demands of software development given the culture in which they work and their normal development practice. Understanding these problems is an essential prerequisite to developing tools, techniques etcetera to support professional end user development