PID control system analysis, design, and technology

Designing and tuning a proportional-integral-derivative (PID) controller appears to be conceptually intuitive, but can be hard in practice, if multiple (and often conflicting) objectives such as short transient and high stability are to be achieved. Usually, initial designs obtained by all means need to be adjusted repeatedly through computer simulations until the closed-loop system performs or compromises as desired. This stimulates the development of "intelligent" tools that can assist engineers to achieve the best overall PID control for the entire operating envelope. This development has further led to the incorporation of some advanced tuning algorithms into PID hardware modules. Corresponding to these developments, this paper presents a modern overview of functionalities and tuning methods in patents, software packages and commercial hardware modules. It is seen that many PID variants have been developed in order to improve transient performance, but standardising and modularising PID control are desired, although challenging. The inclusion of system identification and "intelligent" techniques in software based PID systems helps automate the entire design and tuning process to a useful degree. This should also assist future development of "plug-and-play" PID controllers that are widely applicable and can be set up easily and operate optimally for enhanced productivity, improved quality and reduced maintenance requirements

IC-processed micro-motors: design, technology, and testing

Micro-motors having rotors with diameters between 60 and 120 μm have been fabricated and driven electrostatically to continuous rotation. These motors were built using processes derived from IC (integrated circuit) microcircuit fabrication techniques. Initial tests on the motors show that friction plays a dominant role in their dynamic behavior. Observed rotational speeds have thus far been limited to several hundred r.p.m., which is a small fraction of what would be achievable if only natural frequency were to limit the response. Experimental starting voltages are at least an order of magnitude larger than had been expected (60 V at minimum and above 100 V for some structures). Observations of asynchronous as well as synchronous rotation between the driving fields and the rotors can be explained in terms of the torque/rotor-angle characteristics for the motors

Justifying design and technology

This chapter asks the question why do we teach what we teach in the design & technology curriculum? It traces the emergence of design & technology in the curriculum in England and is in three parts. First it gives a brief account of its precursor - technology education. This is followed by a description of its development within the National Curriculum. The final part discusses some of the issues associated with ‘limiting’ technology education to design & technology

Persuasive technology and digital design for behaviour change

Copyright @ 2012 Social Science Research NetworkThe convergence of the 'digital' and 'real' worlds has been rapid and transformative of everyday life, as well as design practice - to the extent that talking about 'digital design' and 'the digital context' seems anachronistic and redundant. Nevertheless, the arrival of digital technology, the Internet and social media has, from a design perspective, created a new field of a ffordances, constraints, information flows and possibilities. This paper reviews some of the ways in which digital architecture infl uences behaviour, and what the implications could be for designers seeking to infl uence behaviour for social and environmental bene fit. Topics covered include Persuasive Technology, gami fication, Lessig's 'Code is Law' perspective, digital rights management and Zittrain's concept of generativity

Antenna technology: Antenna design and scale model techniques

Prototype antenna design and methods of measuring and predicting antenna characteristics when mounted on space shuttle scale model

Technology update: Tethered aerostat structural design and material developments

Requirements exist for an extremely stable, high performance, all-weather tethered aerostat system. This requirement has been satisfied by a 250,000 cubic foot captive buoyant vehicle as demonstrated by over a year of successful field operations. This achievement required significant advancements in several technology areas including composite materials design, aerostatics and aerodynamics, structural design, electro-mechanical design, vehicle fabrication and mooring operations. This paper specifically addresses the materials and structural design aspects of pressurized buoyant vehicles as related to the general class of Lighter Than Air vehicles

Methods and models of next generation technology enhanced learning - White Paper

Our understanding of learning with technology is increasingly lagging behind technological advancements, such that it is no longer possible to fully understand learning with technologies without bringing together evidence from practice-based experiences and theoretical insight to inform research, design, policy and practice. Furthermore, whilst practical experiences and theoretical insights make significant contributions towards understanding learning with new technologies, the dynamic nature of learner practices and study contexts make it difficult to predict future requirements in terms of methods and models for next generation technology enhanced learning. We therefore require formal and comprehensive methods and models of learning with technology that accommodate theory and practice whilst allowing us to anticipate methodological innovations that capture future transitions and changes in learner practices and study contexts, in order to inform research, design, policy and practice. Workshop participants represented different communities of interest including research, design, evaluation and assessment. The overall objective was to anticipate methodological innovations in technology enhanced learning research and design over the next 5/10 years