78 research outputs found
Fiber Pattern Generation Tools for the Design of Long-Span, Core-Less Wound, Structural Composite Building Elements
No full textThis data set contains tools to generate fiber patterns for tubular surface components as used in the BUGA Fibre Pavilion (Website). The tools allowed to model the fiber patterns as polylines and anchor point sequences which acted as a base for planning the robotic motion paths for prefabrication of the BUGA Fibre composite components.
The surface-based syntax tool generates local support surfaces to keep subsequent fibers in place. The resulting fiber pattern is fully parametric and can be tailored to the specific requirements of different fiber components.
The interlaced syntax tool generates a smooth fiber body by continuously revolving around the component's long axis and alternating between boundary frames. The output is a continuous polyline. In the second step, the resulting fiber net is relaxed to approximate the final anticlastic shape of the fiber lattice.
The reinforcement tool allows the modeling of carbon fiber reinforcement patterns. Following a similar logic as the surface-based tool, the reinforcement wraps around the component and is then relaxed to approximate the final shape of the composite
Upscaled, robotic coreless filament winding methods for lightweight building elements for architecture
No full textStarting in the 1940s, advances in the chemical industry and composite materials such as Fiber Reinforced Polymers have revolutionized manufacturing enabling new lightweight - high strength applications in the aerospace, automotive, and consumer goods industries. However, composites failed to significantly impact the building industry due to its poor digitalization and low integration of design and engineering methods. Nevertheless, these shortcomings can be mitigated through construction-specific design, fabrication methods, and building regulations for composite structures. Especially, lightweight construction has yet to capitalize on the high strength-toweight ratio afforded by composite materials such as Glass or Carbon Fiber Reinforced Polymers and thus shape its contribution to contemporary high-performance, lightweight architecture. However, 21st Century advances in digital design methods in conjunction with newly-available hardware and control systems allow for automated fabrication approaches to re-imagine established fabrication methods such as Filament Winding(FW). This thesis presents novel upscaling and automation strategies for Coreless Filament Winding(CFW), which is an adaptation of FW to construction applications. CFW is a fabrication method that relies on the anisotropic mechanical properties of free-spanning fibers wound around supports in space to create efficient load bearing structures without requiring molds or dies. These strategies are supported by a state-of-the-art review focused on the technological requirements for robotic coreless filament winding in construction applications. The investigation identified fabrication method scalability and insufficient process automation as research gaps in academic investigation for construction composites. The thesis demonstrates that existing prefabrication methods of Robotic Coreless Filament Winding (RCFW) can be successfully upscaled and utilized for large-scale, long-span loadbearing structures. Furthermore, the thesis presents an approach to advance existing process-monitoring and quality-control methods, named Cyber-Physical RCFW (CPRCFW). The two objectives are investigated through two representative tasks: (1) verifying the RCFW method’s scalability and its industrialization potential, and (2) the development of a CPRCFW method for quality control, integrating winding process automation, process monitoring, data acquisition, and analysis. Each objective is demonstrated through the research and development of hardware, consisting of fabrication setups and tooling and software, comprising CAD-implemented industrial robot motion planning and control algorithms. The objectives are verified through large-scale demonstrators at component and building scale, illustrating how the research findings are conducive to RCFW becoming a valid alternative to industry-verified technologies in composite construction applications
Component Data Protocols for the Fabrication of Coreless-Wound Structural Building Components in the BUGA Fibre Pavilion and Maison Fibre
No full textData Protocols for Composite Components of the BUGA Fiber Pavilion (Website) and Maison Fibre (Website) as outcomes of the Feedback-Based Computational Method and Multi-Scalar Design and Evaluation Toolset, described in 'Concurrent Computational Design and Modeling of Structural Coreless-Wound Building Components,' published in Automation in Construction.
The data is the output of the developed design tools and provides a comprehensive geometric and semantic description of the composite components for production. It includes general parameters, defining anchor point counts, material parameters, and a geometrical base plane. The syntax layup provides a layer breakdown of the components including layer count and hooking types. Syntax indices provide the fiber topology of every fiber pattern using a list of anchor point IDs. Abstract path points provide a geometrical description of all fiber patterns by discretizing them into points along equal-length segments. A roving count is provided to give an overview of material amount and distribution. The winding point orientation provides the location and orientation vectors of the anchor points and the geometry section provides geometrical information on the frame assembly
Design to Robotic Production for Informed Materialization Processes
No full textDesign to Robotic Production (D2RP) establishes links between digital design and production in order to achieve informed materialization at an architectural scale. D2RP research is being discussed under the computation, automation and materialization themes, by reference to customizable digital design means, robotic fabrication setups and informed materialization strategies implemented by the Robotic Building group at Hyperbody, TU Delft
Correction to: Two years later: Is the SARS-CoV-2 pandemic still having an impact on emergency surgery? An international cross-sectional survey among WSES members (World Journal of Emergency Surgery, (2022), 17, 1, (34), 10.1186/s13017-022-00424-0)
No full textFollowing the publication of the original article [1], the author name “Dragos Serban” under The WSES COVID-19 emergency surgery survey collaboration group was incorrectly written as “Dragos Seban” instead of “Dragos Serban”. The original article has been corrected
Correction to: Two years later: Is the SARS-CoV-2 pandemic still having an impact on emergency surgery? An international cross-sectional survey among WSES members
No full textFollowing the publication of the original article [1], the author name “Dragos Serban” under The WSES COVID-19 emergency surgery survey collaboration group was incorrectly written as “Dragos Seban” instead of “Dragos Serban”. The original article has been corrected
Correction to: Two years later: Is the SARS-CoV-2 pandemic still having an impact on emergency surgery? An international cross-sectional survey among WSES members (World Journal of Emergency Surgery, (2022), 17, 1, (34), 10.1186/s13017-022-00424-0)
No full textFollowing the publication of the original article [1], the author name “Dragos Serban” under The WSES COVID-19 emergency surgery survey collaboration group was incorrectly written as “Dragos Seban” instead of “Dragos Serban”. The original article has been corrected
Advances in decentralized and stateful access control
No full textThe economy and security of modern society relies on increasingly distributed infrastructures and institutions, such as the banking system, government agencies, and commercial enterprises. This trend raises both the importance of access control technology and its
complexity. Law-Governed Interaction (LGI) represents an advanced access control mechanism that satisfies many of the challenges posed by modern computing. LGI, however, has been defined for asynchronous,
message passing, communication, leaving unsupported the wide range of applications that employ synchronous communication. Furthermore, no formal mechanism had been designed for adapting its policies in the presence of ever-changing security requirements.
My dissertation addresses these issues as follows. It introduces Regulated Synchronous Communication, a novel access control model for synchronous, request-reply communication; it proposes Hot Updates, a mechanism for changing the policy of a distributed system while the system continues to operate.
Regulated Synchronous Communication extends the LGI mechanism to synchronous communication, thus providing advanced control over this important and popular mode of communication. Among the novel characteristics of this model are: the control of both the request and the reply; regulated timeout capability provided to clients, in a manner that takes into account the concerns of their server; and enforcement on both the client and server sides.
Hot Updates addresses the issue of changing the access control policy of a large distributed system, in the context of LGI. Hot Policy Updates undertakes a number of challenges such as a) how to propagate the policy updates throughout the system, b) when to update the policy
with respect to an individual component, and c) how to avoid, minimize or compensate possible inconsistencies that appear during the update
process.
Both Regulated Synchronous Communication and Hot Updates had been implemented using Java Laws, a novel Java-based language for
expressing access control policies for LGI. Java Laws provides a common platform for applying fine-grained access control particularly
suitable for distributed applications written in Java. Among other advantages, Java Laws enables an efficient enforcement of access
control, as well as good scalability and portability across various operating systems.Ph.D.Includes bibliographical references (p. 111-115)
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