3D Assembly Group Analysis for Cognitive Automation

A concept that allows the cognitive automation of robotic assembly processes is introduced. An assembly cell comprised of two robots was designed to verify the concept. For the purpose of validation a customer-defined part group consisting of Hubelino bricks is assembled. One of the key aspects for this process is the verification of the assembly group. Hence a software component was designed that utilizes the Microsoft Kinect to perceive both depth and color data in the assembly area. This information is used to determine the current state of the assembly group and is compared to a CAD model for validation purposes. In order to efficiently resolve erroneous situations, the results are interactively accessible to a human expert. The implications for an industrial application are demonstrated by transferring the developed concepts to an assembly scenario for switch-cabinet systems

Object-orientated registration method for surface inspection of automotive windshields

In this paper we introduce a new point cloud registration strategy for 3D surface inspection, named object-oriented method. Traditionally, the registration methods use a fitting based algorithm, which is a recursive process and too time consuming to do quality inspection. Moreover, the fitting based algorithms require that the measured data and the CAD model have same shapes. Photogrammetry and ICP-based fitting algorithms are commonly used in this area. However, both of them cannot be applied directly to online point cloud registration for quality inspection. Since it requires: 1. no markers on the object surface. 2. a very limited inspection period of time for each part on an assembly line. 3. the measured work piece can not be assumed as same as the CAD model. The online registration is currently demanded by 3D surface inspection in automotive glasses manufacturing industry. The object-oriented registration method is developed based on matching the invariant geometric features between two data sets instead of the artificial markers and the recursive fitting algorithms. Therefore the registration speed is much higher. A datum filter is developed to extract the invariant features from the measured point cloud, based on the information that the CAD model carries. The curvature information and moment values are used as characteristic features to design the filter. The registration matrix is calculated by the invariance parts in both data sets. The new online registration method has been applied to the quality inspection in the windshield manufacturing industry. Experimental results are presented in this paper to demonstrate the effectiveness of the developed strategy. ©2008 IEEE.Link_to_subscribed_fulltex

Developing a multiple glazing system to minimize transmission of direct insolation for particular latitudes

Too often, in the last 50 years, the energy-thrift lessons of vernacular architecture have been forgotten or ignored. In the Middle East, many recently-designed commercial buildings, with large areas of glazing, incur excessively high electricity-demands to provide energy for the required air-conditioning plant. One way of reducing the magnitude of this demand is through better window design. A new glazing system is proposed that utilizes the insertion of a clear glazing element within the cavity of a double glazed window. The main objective of this system is to achieve acceptable levels of daylight within a building by attempting to maintain the diffuse component of insolation while reducing the penetration of direct component by using the increased reflectivity of these materials with the angle of incidence of the direct beam component of solar irradiation. By using clear glazing materials the proposed system attempts to achieve acceptable performance without the need for elaborate and expensive coatings or substrates. Because solar geometry varies with latitude a varying performance of glazing systems is expected with current glazing systems. However, the suggested system utilizes an optimal angle for overall daylighting and thermal performance that relates to the particular solar geometry of interest, New software is also developed to assess the performance of the suggested system; this involved examining all the modes of heat transfer through the entire glazing system. Results then were assessed to calculate the optimal angle of the element that corresponds to the solar geometry of particular latitude. Such proposal takes a new perspective, once it is acknowledged that though different forms of advanced glazing systems currently are being used to inhibit the penetration of direct solar radiation, still the main disadvantages of such advanced glazing systems are that they are relatively expensive and would reduce the penetration of a considerable part of the daylight entering the space

Extending BIM for air quality monitoring

As we spend more than 90% of our time inside buildings, indoor environmental quality is a major concern for healthy living. Recent studies show that almost 80% of people in European countries and the United States suffer from SBS (Sick Building Syndrome), which affects physical health, productivity and psychological well-being. In this context, environmental quality monitoring provides stakeholders with crucial information about indoor living conditions, thus facilitating building management along its lifecycle, from design, construction and commissioning to usage, maintenance and end-of-life. However, currently available modelling tools for building management remain limited to static models and lack integration capacities to efficiently exploit environmental quality monitoring data. In order to overcome these limitations, we designed and implemented a generic software architecture that relies on accessible Building Information Model (BIM) attributes to add a dynamic layer that integrates environmental quality data coming from deployed sensors. Merging sensor data with BIM allows creation of a digital twin for the monitored building where live information about environmental quality enables evaluation through numerical simulation. Our solution allows accessing and displaying live sensor data, thus providing advanced functionality to the end-user and other systems in the building. In order to preserve genericity and separation of concerns, our solution stores sensor data in a separate database available through an application programming interface (API), which decouples BIM models from sensor data. Our proof-of-concept experiments were conducted with a cultural heritage building located in Bled, Slovenia. We demonstrated that it is possible to display live information regarding environmental quality (temperature, relative humidity, CO2, particle matter, light) using Revit as an example, thus enabling end-users to follow the conditions of their living environment and take appropriate measures to improve its quality.Pages 244-250

Waste sector small and medium-sized enterprises and their role in the extended producer responsibility; a case study of environmental responsibility in SMEs in eThekwini, KwaZulu-Natal (South Africa).

Masters Degree. University of KwaZulu-Natal, Pietermaritzburg.Both the waste sector and corporate enterprises, under the banner of corporate social and environmental responsibility (CSER), have a role to play in sustainable development, particularly in the South African context where legislation supports the waste hierarchy in its approach to waste management, and the promotion of employment and small and mediumsized enterprises (SMEs). SMEs, due to their vast number and the significance of their aggregate contribution to the global economy, have been identified as key contributors to sustainable development. Global supply chains rely heavily on SME suppliers and service providers, yet the combined environmental impact of SMEs remains un-quantified and their engagement in CSER is underexplored. This research explores the role that SMEs play in extended producer and environmental responsibility from a waste management perspective in the eThekwini Municipal area, describes the barriers that SMEs face when implementing environmental measures and provides a critical assessment of environmental responsibility in waste management supply chains. Case studies, where interviews and documentations were used as data collection methods, on waste management supply chains are provided. It is evident that there is a culture of outsourcing of the waste management function in the eThekwini municipal area and SMEs are an important component of the waste management value chain. However, environmental responsibility amongst the SMEs is poor as the SMEs response to supply chain or legislative pressure is weak. The bureaucracy of legal requirements of the waste sector, an ill-informed public and business sector regarding environmental issues, and the highly competitive nature of the waste sector are common obstacles experienced. In the face of difficulties such as limited resources, some SMEs are responding to legislative pressure and adopting the ISO 14001 certification. Many SMEs are responding to supply chain pressure in terms of the Broad Based Black Economic Empowerment Act and participating in social responsibility activities. Findings from this research support the government’s vision of the creation of employment, the promotion of small business within the waste sector and the role that SMEs play in sustainable development in South Africa however; there is a need for strategies to address the environmental problems of small business

Aeronautical engineering: A continuing bibliography with indexes (supplement 257)

This bibliography lists 560 reports, articles, and other documents introduced into the NASA scientific and technical information system in September 1990. Subject coverage includes: design, construction and testing of aircraft and aircraft engines; aircraft components, equipment and systems; ground support systems; and theoretical and applied aspects of aerodynamics and general fluid dynamics

Territorial Violence and Design, 1950-2010: A Human-Computer Study of Personal Space and Chatbot Interaction

Personal space is a human’s imaginary system of precaution and an important concept for exploring territoriality, but between humans and technology because machinic agencies transfer, relocate, enact and reenact territorially. Literatures of territoriality, violence and affect are uniquely brought together, with chatbots as the research object to argue that their ongoing development as artificial agents, and the ambiguity of violence they can engender, have broader ramifications for a socio-technical research programme. These literatures help to understand the interrelation of virtual and actual spatiality relevant to research involving chatrooms and internet forums, automated systems and processes, as well as human and machine agencies; because all of these spaces, methods and agencies involve the personal sphere. The thesis is an ethical tale of cruel techno-science that is performed through conceptualisations from the creative arts, constituting a PhD by practice. This thesis chronicles four chatbots, taking into account interventions made in fine art, design, fiction and film that are omitted from a history of agent technology. The thesis re-interprets Edward Hall’s work on proxemics, personal space and territoriality, using techniques of the bricoleur and rudiments (an undeveloped and speculative method of practice), to understand chatbot techniques such as the pick-up, their entrapment logics, their repetitions of hateful speech, their nonsense talk (including how they disorientate spatial metaphors), as well as how developers switch on and off their learning functionality. Semi-structured interviews and online forum postings with chatbot developers were used to expand and reflect on the rudimentary method. To urge that this project is timely is itself a statement of anxiety. Chatbots can manipulate, exceed, and exhaust a human understanding of both space and time. Violence between humans and machines in online and offline spaces is explored as an interweaving of agency and spatiality. A series of rudiments were used to probe empirical experiments such as the Prisoner’s Dilemma (Tucker, 1950). The spatial metaphors of confinement as a parable of entrapment, are revealed within that logic and that of chatbots. The ‘Obedience to Authority’ experiments (Milgram, 1961) were used to reflect on the roles played by machines which are then reflected into a discussion of chatbots and the experiments done in and around them. The agency of the experimenter was revealed in the machine as evidenced with chatbots which has ethical ramifications. The argument of personal space is widened to include the ways machinic territoriality and its violence impacts on our ways of living together both in the private spheres of our computers and homes, as well as in state-regulated conditions (Directive-3, 2003). The misanthropic aspects of chatbot design are reflected through the methodology of designing out of fear. I argue that personal spaces create misanthropic design imperatives, methods and ways of living. Furthermore, the technological agencies of personal spaces have a confining impact on the transient spaces of the non-places in a wider discussion of the lift, chatroom and car. The violent origins of the chatbot are linked to various imaginings of impending disaster through visualisations, supported by case studies in fiction to look at the resonance of how anxiety transformed into terror when considering the affects of violence

The influence of oxide deposits on the remaining life and integrity of pressure vessels equipment

In this paper is presented the principle of application of fracture mechanics parameters in determining the integrity of rotary equipment. The behavior of rotary equipment depends on presence of cracks and basically determines the integrity and life of such equipment. The locations of stress concentration (i.e. radius changes) represent a particular problem in rotary equipment, and they are the most suitable places for the occurrence of microcracks i.e. cracks due to fatigue load. This problem is most common in the shaft of relatively large dimensions, for example, turbine shafts in hydropower plants made of high-strength carbon steel with relatively low fracture toughness, and relatively low resistance to crack formation and growth. Having in mind that rotary equipment represents the great risk in the exploitation, whose occasional failures often had severe consequences, it is necessary detail study of their integrity. For this purpose, it is necessary application of parameters of linear-elastic fracture mechanics, such as stress intensity factor, which range defines the rate of crack growth (Parisian law), and its critical value (fracture toughness) determines the critical crack length. The procedures for determining the critical crack length will be described using the fracture mechanics parameters

Numerical analysis of fatigue crack growth in welded joints with multiple defects

In the case of welded steel structures (such as pressure equipment), welded joints are often critical location for stress concentrations, due to different mechanical properties and chemical composition compared to the parent material, and due to changes in geometry. In addition, the presence of imperfections (defects) in welded joints can contribute to the increase in local stress, resulting in crack initiation. Recently, standards that are related to acceptable dimensions of various types of defects in welded joints started taking fatigue loading into account as well. For the purpose of this research, a 3D numerical model was made, of a welded joint with different types of defects (linear misalignment and a crack in the weld metal), based on the previous work, which involved static loading of the same specimen. In this case, fatigue was taken into account, and the simulation was performed using ABAQUS software, as well as Morfeo, an add-on used for determining the fatigue behaviour of structures via XFEM (extended finite element method). The welded joint was made using steel P460NL1 as the parent material, and EPP2NiMo2 wire was used for the weld metal. An additional model was made, whose defects included a crack and an overhang. Fatigue crack growth analysis was performed for this model as well, and the results for stress intensity factors and stress/strain distribution were compared in order to obtain information about how different defects can affect the integrity of a welded joint