Behavioral Design and Adaptive Robotic Fabrication of a Fiber Composite Compression Shell with Pneumatic Formwork

7.0 ROBOTICS/RESPONSIVE ENVIRONMENTS 2 | UNIVERSITY OF STUTTGART

BEHAVIORAL DESIGN AND ADAPTIVE ROBOTIC FABRICATION OF A FIBER COMPOSITE COMPRESSION SHELL WITH PNEUMATIC FORMWORK

Lauren Vasey ABSTRACT Institute for Computational Design (ICD) This paper presents the production and development of an adaptive robotically University of Stuttgart fabricated fiber composite compression shell with pneumatic formwork as a case study Ehsan Baharlou for investigating a generative behavioral design model and an adaptive, online mode Institute for Computational Design (ICD) University of Stuttgart of production. The project builds off of previous research at the University of Stuttgart on lightweight fiber composite structures which attempts to reduce the necessary Moritz Dörstelmann Institute for Computational Design (ICD) formwork for fabrication while simultaneously incorporating structural, material and University of Stuttgart fabrication logics into an integrative computational design tool. This paper discusses Valentin Koslowski the design development and fabrication workflow of the project, as well a set of Institute of Building Structures and strategies which were developed for online robotic programming in response to live Structural Design (ITKE) sensor data. University of Stuttgart Marshall Prado Institute for Computational Design (ICD) University of Stuttgart Gundula Schieber Institute of Building Structures and Structural Design (ITKE) University of Stuttgart Achim Menges Institute for Computational Design (ICD) University of Stuttgart Jan Knippers Institute of Building Structures and Structural Design (ITKE) University of Stuttgart

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1 INTRODUCTION The production of large scale fiber composite structures is primarily limited to a small set of traditional fabrication techniques. While their degree of automatization and the achieved composite part quality is partially very advanced, they typically require costly full scale molds due to the necessity to apply high pressures and heat to compact the composite plies (Shirinzadeh et. al 2004). Beyond exhausting unnecessary resources for this formwork, these modes of production are viable only for serialized production of identical parts making their usefulness for novel architectural applications insufficient. In the ICD/ITKE Research Pavilion 2012, a robotic coreless filament winding process was developed which eliminated the need for surface molds through the use of a minimal, full-scale frame. This allowed the fabrication of a single reinforced monocoque shell through the subsequent tensioning of the wrapped fibers which formed hyperbolic composite surfaces with differentiated fiber orientations. In the ICD/ITKE Research Pavilion 2013-14, this minimal frame concept was expanded to create a double layered component based construction system which further reduced unnecessary formwork by utilizing a reconfigurable kit of parts for winding frame assemblies. This greatly expanded design solution space by opening up the opportunity to create a wide range Figure 1 of performative geometries with minimal material investment. In the presented paper, an ICD/ITKE Research Pavilion 2014/2015. The pavilion alternative process is suggested to eliminate superfluous formwork, not only by minimiz- demonstrates the potential of online control and robotic fabrication in expanding the potential formwork for fiber ing the material used for its construction but also through its functional integration into composite structures. a fiber composite compression shell building system using pneumatic formwork that transitions into a building envelope.

2 BIOLOGICAL ROLE MODEL The ICD ITKE Research Pavilion 2014-15 was conceptualized through the biological investigation of the water spider (Argyroneta aquatic). This spider builds its underwater habitat by systematically reinforcing a captured air pocket from the inside through various silk laying behaviors. This process serves as a relevant role model for fiber composite fabrication strategies in architectural applications. In comparison to previous fiber composite production techniques the initial formwork is functionally integrated in the later composite shell, and the resulting construction exhibits a highly articulated anisotropic organization of fibers.

Figure 2 Microscopic image of the water spider’s fiber composite habitat. The water spider’s anisotropic fiber arrangements include anchor threads, bundled threads, and distributed threads. 7.0 ROBOTICS/RESPONSIVE ENVIRONMENTS 2 | UNIVERSITY OF STUTTGART

The underlying principles of the silk placement procedure were abstracted and transferred into a fabrication strategy for local fiber reinforcement of a double curved pneumatic membrane. Of primary consideration, particularly for the development of the computational tool, was the set of behaviors that the spider employs, the order of the construction sequence, and the hierarchical arrangement of fibers which exhibit performative structural characteristics.

3 SYSTEM DEVELOPMENT Out of the initial biological investigations emerged the concept for a prototypical architectural system in which a six axis robot would iteratively apply extruded fibers onto the interior of an inflated membrane, allowing the membrane under tension to slowly transition into a stable fiber composite compression shell. To provide the minimized formwork for construction, an Ethylene tetrafluoroethylene, (ETFE) membrane is inflated, encompassing a Kuka KR 120 R3900 industrial robot at its center. Epoxy resin, pre- impreg- nated fibers are sequentially applied to the membrane at a controlled pressure, allowing the inflated pneumatic to be gradually reinforced. An important challenge of such a process, is its fluctuating and rather unpredictable nature: in which both the actual shape of the membrane after inflation, and the deflections due to the applied loading during the fabrication process, could be simulated but not determined within a margin of error to allow for a consistent fiber application pressure. This imprecision could only be dealt with through a cyber-physical fabrication process which connected the robotic actions directly with sensor feedback.

Figure 3 An inflated pneumatic is iteratively reinforced through the robotic placement of carbon fiber, allowing the membrane to slowly transition into a stable compression shell.

To meet this goal, a custom robotic end effector for fiber deposition and sensor integration was developed and houses four interchangeable spools of pre-impregnated carbon fibers, a motor controlled fiber extruder, a roller which applies the extruded fiber onto the membrane and a load cell to measure the force between the effector and membrane. This force is directly transferred through a connected hinge plate to the load cell that relays its signal value to the computational model on the networked computer client for processing. This provides real time data of the application force for laying the fibers.

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Another important challenge in this process arose from the use of the membrane as a negative mold. The fibers, when put under tension during the application process, can easily delaminate from the ETFE surface. A motor driver, which receives signals from the network client, allows the synchronization of the robot speed with the extrusion speed of the fibers to minimize the tension that the effector exerts on the previously laid fibers. The effector also holds a pressurized automated spray device, which applies a composite glue mixture to the path 30 centimeters before the fibers are applied. A relay connected to a solenoid valve controls when power is supplied to the spray device, allowing small volumes of glue to be sprayed in coordination with the movement of the robot. This secondary glue allows the fibers to adhere to the relatively non-stick surface, within a short period of time even against the active force of gravity.

4 DESIGN IMPLEMENTATION To implement a working design for a full scale demonstrator of a continuous fiber extrusion and application process, it was critical to establish a design method which allows for the integration and negotiation of various boundary conditions. A two-step strategy was employed where the initial design space was determined through negotiation of Figure 4 To provide the minimized formwork for construction, an constraints enabled by the specific robotic fabrication setup and the solution space of Ethylene tetrafluoroethylene, (ETFE) membrane is inflated, possible inflatable membrane geometries. In a subsequent step the fiber layout of the encompassing a Kuka KR 120 R3900 industrial robot at its center, which sequentially applies fibers to the membrane. structural shell was generated by agent-based design methods. The layering of various agent behaviors allowed for simultaneous integration of multiple design drivers and led to emergent fiber path layouts. The results satisfy various performance criteria and resolve their reciprocal relationships to a degree that would not be achievable within a completely top down design strategy.

As one of the predominant design drivers, the constraints of the specific robotic fabrication setup had to be analyzed and integrated into the design process. While the first axis of the six axis robot has a working range of over 360 degrees, it is not a continuous axis; therefore, a continuous fiber could not be placed across the axis of discontinuity, where the solver is between its two extreme positions at -185 to + 185 degrees. In addition, the Kuka KR 120 is a six axis robot that is typically mounted on a pedestal above its workpiece, and thus has a greater range of kinematic freedom due to axis limits below its base rather than above it. Because of this robot specific constraint, it was essential to determine the active robotic reach envelope, a solution space where the inflated membrane, considering the aggregation of all possible tolerances, would lie within.

The abstract three dimensional representations of robotic reach envelopes released by the manufacturers do not adequately represent the project-specific, hyper-dimensional solution set of reachable positions that exist in a given volume inclusive of all possible orientations. Additionally they fail to consider path continuity, where two given points may both be reachable, but a route from one to the other may not be possible. To create a reach envelope that would reflect both orientation specific feasibility as well as 7.0 ROBOTICS/RESPONSIVE ENVIRONMENTS 2 | UNIVERSITY OF STUTTGART

continuity, it was necessary to implement a few assumptions. Because the first axis of the robot is a rotational axis, if any single position in a plane could be reached, than the self-similar position achieved through a rotation around the Axis 1 is also valid. There- fore, the volume can be represented as a rotation of a two dimensional reach envelope, revolved around the Z-axis of the world coordinate system at the base of the robot. Additionally, if one tool center point (TCP) position was reachable, then any rotation around the Z-axis of the TCP would also be valid through a simple rotation of axis 6. The remaining degree of freedom of any position in space can be resolved by considering that the normal of the tool would be aligned with the normal of the pneumatic membrane that, if purely spherical, would point in the direction away from the robot base.

Of the 6 robotic axes, any given solution can be mirrored around 3 of the six axes. This results in a hypothetical solution set of 8 inverse kinematic solutions, each of which has its own unique reach envelope due to self-collisions and axis limitations. To switch from one kinematic solution to the other mid-path would essentially elongate the mirrored axis, extending the tool into the membrane; a continuous path could only be realized while one inverse kinematic configuration was active.

Figure 5 Robotic Reach Envelope. A comparison of the reach envelope of different inverse kinematic configurations. A continuous fiber path can only be placed in a single configuration.

Once the design for the membrane was simulated, this reach envelope could become more refined. In this case, the simulated inflated mesh is discretized into a set of positions, and each position is passed through a solver to check whether the point was reachable and within a minimum and maximum tolerance. If both extreme conditions are reachable, the position is added to the three dimensional solution set. Two inverse kinematic configurations emerged as the primary configurations for use: one which had a significant working envelope at the base, and a second which had a more significant working envelope at the top, allowing considerable overlap (Figure 5).

This reach envelope was continuously refined throughout the process of construction reflecting both the actual position of the membrane relative to the robot base and the

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current stiffness and deflections of the membrane. Though initial assumptions required that the tool be normal to the membrane, it was also possible to utilize an additional rotational degree of freedom, whereby the effector could rotate around the axis of the application roller. In this case a behavioral method is utilized to derive the necessary rotations at each discretized position: for each simulated position, the robot rotates the end effector—until a position is reached—and stores the value to be applied in the generation of the robotic control code.

Figure 6 Orientation Mapping. A single rotation around the application roller of the end effector expands the robotic reach, allowing all positions on the actual constructed membrane to be achieved in a single inverse kinematic configuration.

5 COMPUTATIONAL MODEL For this project, a computational method was developed to integrate the robotic fabrication constraints directly into the composite design, by computing the toolpath of the robot with an agent-based design system. In this case, the robot acts as a physical agent; its behavior is influenced by the behavior and construction sequencing of the biological role model, the desired structural and mechanical properties of the system, and the active constraints specific to the robotic setup. A necessary process of abstrac- tion allowed each of these inputs: material, fabrication, and biologic, to be translated into a set of behavioral logics, each informed by critical environmental information, including stimuli, boundary conditions, and robotic limitations.

In the behavioral computational model, the schematic design and agent environment, is represented as a high resolution mesh capable of iteratively storing information or process parameters locally in the attributes of the mesh faces. These properties can include: vectors representing the principal stress directions and magnitudes; repulsion forces around axis one of the robot and the openings of the pavilion; and localized knowledge of desired and actual fiber densities. A field of vision allows the agent to access the active behaviors and stored values in its local vicinity in the direction of movement. For example, the agent can perceive the paths laid previously—a stimulus which can trigger a behavior in which the agent maintains a certain distance from the path. In areas of high stress, the agent will stay closer to previously laid paths than in others, resulting in material accumulation in areas of desired structural depth. With each 7.0 ROBOTICS/RESPONSIVE ENVIRONMENTS 2 | UNIVERSITY OF STUTTGART

iteration of the agent code, every input behavior is translated into a weighted target direction, the summation of which influences the agent’s next position and thus the continuation of the fiber path (Arkin 1998). Such a process allows for the negotiation of multiple constraints and conflicting inputs in the computational tool, allowing hierarchical design explorations through the manipulation of the relative weight and process parameters of each behavior. Such a process allows a negotiation between top down design decisions, and bottom-up stochastic emergent qualities that are the unforeseen consequence of many varied inputs.

A key aspect of this behavior system is how it could be informed by structural analysis. A finite element simulation in which the pavilion was modelled as a continuous shell structure with an artificial isotropic material was initially performed to investigate the principal stress directionality considering magnitude with respect to self-weight and wind load. Where high absolute minimum and maximum principal stresses occurred, many different fiber directions were foreseen to achieve a quasi-isotropic material behavior. In locations where the absolute value of one principal stress was dominant only, a fiber direction along those lines with was planned with additional reinforcement layers in an angle of 60° towards the fiber axis.

Figure 7 Sample composite of many different fiber layers derived from the agent base computational model.

6 ADAPTIVE FABRICATION PROCESS Traditional digital fabrication processes are generally programmed off-line through instruction based commands which are static, predetermined, and inflexible. This particular production setup was extremely unpredictable due to the nature of inflation and applied loading during construction, thus necessitating an adaptive fabrication process. To achieve this flexibility, online communication between the robot, a computer server, and the devices of the custom robotic effector directly allowed live modification of an intended fiber path. Online adaptive instructions negotiate critical construction information (i.e. pressure feedback from integrated sensors) to maintain criteria for fiber

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extrusion on the active pneumatic membrane. Additionally, the actual fiber path is continuously recorded, allowing the live deflections of the pneumatic to be calculated, and re-incorporated into the next iteration of the agent based model.

6.1 COMMUNICATION MODEL A communication strategy was developed to distribute information and process the signals between the various devices and different environments. Enabled through the Kuka Robotic Sensor Interface (RSI), Ethernet packages are streamed via user data pro- tocol over a network between the server, which handles data communication, the client, which was used for data processing and control, the robot, and the secondary sensor input and output devices of the extruder.

In one single cycle iteration of the fiber laying process, the current position of the robot is streamed from the robot to the server. The server passes this information to a client, which relates the robot’s position to a digital representation of the membrane. The client calculates the vector of retract in the current tool coordinate system of the robot, then Figure 8 uses the deviation of the current pressure to determine the magnitude of the retract. Realtime Fabrication Feedback. The current robot position is streamed to a client computer which relates the position to a The client then sends the current speed to both the motor and spray device (Figure 9). global model of the membrane. The pressure is processed by In this model, signal processing is done outside of the robot control but inside the design the client, which sends a correction value back to the robot. environment. This technique sacrifices the processing speed of a single iteration that, at the minimum, could be reduced to 12 milliseconds, but it also facilitates the probabilis- tic determination about the current status of production, making use of the geometric libraries and scripting engines native to the design environment.

Figure 9 Iterative Signal Processing during fiber placement. The agent code outputs approximate robotic control code which is executed on the robot. During the execution of the code, the path is modified based on pressure data, and the state of the effector devices is continually updated based on the current speed of the robot. 7.0 ROBOTICS/RESPONSIVE ENVIRONMENTS 2 | UNIVERSITY OF STUTTGART

6.2 BEHAVIORAL PRESSURE RESPONSE Several factors had to be iteratively determined for the process to be successful. For example, to determine if the extruder was in contact with the membrane, a threshold contact force had to be exceeded and the current robot position had to be within a distance to the membrane. This boolean condition determined whether the motor was actively extruding or not. Additionally, several different factors would affect the pressure reading, including the relative rotation of the tool around world coordinate system Z-axis, which would increase the self-weight of the tool acting on the load cell. The relative angle of the application roller to the normal of the membrane also would affect the pressure reading when the force was not directly perpendicular to the load cell.

A pressure range parameter determines the minimum deviation of the current pressure and from the target pressure. Outside of this threshold, the magnitude of the correction movement is scaled linearly, where a greater deviation from the target pressure produces a greater correction value, represented as a correction velocity in the normal direction towards or away from the membrane. For the system to be correctly calibrated, the maximum correction speed had to be coordinated with both the current speed of the robot and the tolerances of the current control code.

6.3 ONLINE CORRECTION AND PROGRAMMING Two modes of online correction were tested and developed for use in the project; each offered various degrees of freedom and advantages. In the first model, the robot’s path was completely determined and streamed online, making it capable of being altered rap- idly in response to target information. This approach has several shortcomings, primarily due to the large delay in processing time and inconsistency in the signals. Though this method is clearly the most autonomous, the delay causes instability and discontinuous motion. Additionally, the robot orientation is represented by Euler values, rather than quaternions, which requires methods for linearly and continuously interpolating. This mode of online correction remains an active subject for investigation and development and was prototyped but not implemented in the large scale construction.

The second method of online control is considered path correction whereby the path of the robot is roughly known and predefined in the control code, but modifications can be streamed, in this case, relative to the current tool coordinate system. In this method, the robot’s velocity is always a summation of the relative movement in the control code as well as the streamed correction movement. This second method is quite flexible and open ended as the relative speeds of each input can vary throughout the process. For example, the program speed can be set to zero to allow complete freedom through the online motion, or correction can be disabled, allowing the program to fully control the movement of the robot.

6.4 RECORDING AND PROCESSING CONSTRUCTION DATA The live communication between the design environment and the robot also facilitated

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a digitization of the actual construction process, where the actual fiber path is continuously recorded, allowing the live deflections of the pneumatic to be calculated and re-incorporated into the next iteration of the agent-based model. This capability was important, as the agent code could be reiterated quickly in response to unexpected changes, for example, as in the time of the fabrication process. In addition, by reas- sessing the current deformed state of the membrane, large accumulations of material could be anticipated, enhancing the ability of the effector to negotiate areas of increased fiber density or built-up structural thickness. This feedback allowed the stiffness of the structure to be revealed as a function of time. Such a maneuver moves away from traditional design methods whereby all structural calculations and design decisions are made prior to construction.

7 RESULTS AND DISCUSSION The potential of the developed cyber-physical fabrication method was explored through a full scale architectural demonstrator. The 1:1 scale prototype covers an area of 40m²and encloses a volume of 125 m. Though the developed process lacked con- Figure 10 sistency at times, and needs further refinement for architectural application, the end The ICD/ITKE Research Pavilion 2014/2015. The 1:1 scale effector and adaptive robotic process was utilized to successfully automate the place- prototype covers an area of 40 m² and encloses a volume of 125 m3. ment of 9 twisted 48 k rovings simultaneously at a speed of approximately .01 meters per second, or 1 kilogram per hour, on an active, inflated membrane in which tolerances exceeded 15 cm.

The resulting differentiated fibrous texture of the demonstrator is not only structurally performative but also achieves a variety of architectural expressions, varying between gradual densities and transparencies. The true potential of the process is to enable the fabrication of highly specific anisotropic fiber arrangements, whereby a material system can be specifically designed to integrate various inputs and satisfy multiple criteria. In addition, the developed cyber physical fabrication workflow demonstrated the power of Figure 11 sensor implementation and online control in expanding the range of potential formwork Aerial View of the ICD/ITKE Research Pavilion 2014/2015. for fiber based systems.

8 CONCLUSION This project demonstrates that many characteristic problems encountered in fabrication workflows can be solved behaviorally where exact process parameters or system vari- ables cannot be known precisely, but in which opportunistic behavior can be enacted to restore an equilibrium (or ideal state) live during the process of fabrication. This project calls into question the typical linearity of the processes of design and realiza- tion, but it also engenders greater questions about the role of behavioral generative strategies, particularly as they begin to fuse with online robotic fabrication control. The project questions whether the ultimate goal of such a fabrication process is to derive an autonomous robotic agent, capable of making design decisions through embedded 7.0 ROBOTICS/RESPONSIVE ENVIRONMENTS 2 | UNIVERSITY OF STUTTGART

behavioral logics, thereby overturning established linear file-to-factory design protocols. Arguably, the method employed here does not deviate from established methodologies in which behavioral strategies are employed generatively, but the designer maintains the ability to evaluate the output of the behavioral process before enabling its production. Several avenues of future development are manifest: in particular, a further synthesis of design and production, whereby online decision making embedded in a systematic and behavioral model can be informed by targeted sensor feedback during the construction process. Design and production, rather than operating as separate stages in the construction process, would unfold synchronously and non-deterministically. Such a process ultimately relates more to construction systems in nature, whereby performative morphologies develop through behavioral adaptation to changes in external stimuli.

ACKNOWLEDGEMENTS The work presented in this paper is part of a joint project between the University of Stutt- gart and the University of Tübingen. The authors would like to express their gratitude towards their fellow investigators: Prof. Oliver Betz, Institute of Evolution and Ecology, Evolutionary Biology of Invertebrates, University of Tübingen; Prof. James Nebelsick, Department of Geosciences, Paleontology of Invertebrates, University of Tübingen; Dr.- Ing. Thomas Stehle, Rolf Bauer, and Michael Reichersdörfer of the Institute for Machine Tools, Universität Stuttgart; Stefan Carosella, Prof. Dr.-Ing. Peter Middendorf of the Institute of Aircraft Design, University of Stuttgart.

The project was partially funded by: KUKA Roboter GmbH, GettyLab, did aiRstruc- tures, SGL Carbon SE, Sika Germany GmbH, Daimler AG, Walther Spraying and coat- ing systems GmbH, Lange + Ritter GmbH, Gibbons Fan Products Ltd, igus GmbH, Peri GmbH, HERZOG Maschinenfabrik GmbH & Co. KG, AFBW - Allianz fiber-based materials Baden-Württemberg eV, Reinhausen Plasma GmbH, Reka Klebetechnik GmbH, HECO-Schrauben GmbH & Co. KG, Airtech Europe SA, Mack scaffolding GmbH, ren- tes, steel construction Wendel GmbH + Co. KG, CARU Containers GmbH , EmmeShop Electronics, STILL GmbH, SH Electrical, GEMCO, and Zeppelin Rental GmbH & Co. KG. In addition, the authors would like to thank all the students who worked on the project, in particular to Julian Holl and Kenryo Takahashi for playing important development roles on the aspects of the project discussed here: RSI implementation and the Agent code, respectively, and Emily Scoones for her heroic effort in coordinating the project. Thanks to the other researchers Benjamin Felbrich, Manfred Hammer, Axel Körner, Anja Mader, Seiichi Suzuki who generously donated their time and efforts and to Michael Preisack and Michael Tondera for their technical support.

The image credits are as follows: Figure 1, © Roland Halbe (2015); Figures 2-11, © ICD/ ITKE University of Stuttgart (2015).

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REFERENCES Arkin, R.C. (1998). Behavior-based Robotics. London: The MIT Press. Dörstelmann, M., S. Parascho, M. Prado, A. Menges, J. Knippers. (2014). In ACADIA 2014: Integrative Computational Design Methodologies for Modular Architectural Fiber Composite Morphologies, ACADIA Conference, October 23 - 25, Los Angeles. Menges, A. (2015). The New ‘Cyber-Physical Making’ in Architecture: Computational Construction. Architectural Design 85(4). London: Wiley Academy. Menges, A. and J. Knippers. (2015). Fibrous Tectonics. Architectural Design 85(4). London: Wiley Academy. Parascho, S., M. Dörstelmann, M. Prado, A. Menges, J. Knippers. (2015). Modular Fibrous Morphologies: Computational Design, Simulation and Fabrication of Differentiated Fibre Composite Building Components. In Advances in Architectural Geometry 2014, eds. P. Block, J. Knippers, N.Mitra, W.Wangl, pp. 29-45. Reichert S., T. Schwinn, R. La Magna, F. Waimer, J. Knippers, A. Menges. (2014). Fibrous Structures: An Integrative Approach to Design Computation, Simulation and Fabrication for Lightweight, Glass and Carbon Fibre Composite Structures in Architecture based on Biomimetic Design Principles. CAD Journal 52: 27-39. Shirinzadeh, B., G. Alici, C. Foong, G. Cassidy. (2004). Fabrication Process of Open Surfaces by Robotic Fiber Placement. Robotics and Computer-Integrated Manufacturing 20: 17-28. 7.0 ROBOTICS/RESPONSIVE ENVIRONMENTS 2 | UNIVERSITY OF STUTTGART

LAUREN VASEY GUNDULA SCHEIBER

Lauren Vasey is a Research Associate at the Institute for Gundula Scheiber is a Research Assistant at the Institute Computational Design (ICD) at University of Stuttgart. She of Building Structures and Structural Design (ITKE) at the received a Bachelor of Science (cum laude) in Engineering from University of Stuttgart. She graduated in 2011 from the Tufts University, and a Masters of Architecture with distinction University of Stuttgart and worked in several architectural from the University of Michigan. She has taught several offices. Her work has won various awards including the German workshops and courses in computational design and robotic Steel Construction Award for Students, the Architecture Award fabrication and has worked previously at the University of of the Cultural Resort of German Economy, the Diploma Award Michigan Taubman College FAB Lab as well at the Swiss Federal of the Faculty of Architecture and Urban Planning and the Award Institute of Technology (ETH-Zurich), Chair for Architecture and for outstanding scientific achievements from the University Digital Fabrication. of Stuttgart. Her main research focuses on the investigation of compliant mechanisms found in movable exoskeletons of EHSAN BAHARLOU arthropods and the transfer of their underlying principles into Ehsan Baharlou is a doctoral candidate at the Institute for adaptive structures for architecture. Computational Design (ICD) at University of Stuttgart. He holds a Master of Science in Architecture with distinction from MARSHALL PRADO the Islamic Azad University of Tehran. Along with pursuing his Marshall Prado is a Research Associate for the Institute for doctoral research, he has taught seminars at the ICD since 2010. Computational Design at the University of Stuttgart. He holds a Bachelor of Architecture from North Carolina State University MORITZ DÖRSTELMANN and advanced degrees as a Master of Architecture and a Master Moritz Dörstelmann is a Research Associate at the Institute for of Design Studies in Technology from the Harvard University Computational Design (ICD) at the University of Stuttgart. He Graduate School of Design. His current research interests include started his architecture studies at the RWTH Aachen University the integration of computation and fabrication techniques into in 2005. In 2011 he graduated with distinction from University material systems and spatial design strategies. of Applied Arts in Vienna where he studied in the master class of Zaha Hadid and Patrik Schumacher. The focus of Moritz’s PROFESSOR ACHIM MENGES research is the investigation of biological fiber based structures, Professor Achim Menges, born 1975, is a registered architect regarding functional integration, structural performance and and professor at the University of Stuttgart, where he is the material organization strategies, and transfer of their underlying founding director of the Institute for Computational Design since principles into architecture by integrative design processes 2008. He is also Visiting Professor in Architecture at Harvard employing computational design strategies and digital University’s Graduate School of Design since 2009. fabrication. PROFESSOR JAN KNIPPERS VALENTIN KOSLOWSKI Professor Jan Knippers specializes in complex parametrical Valentin Koslowski is a Research Assistant at the Institute generated structures, as well as the use of innovative materials. of Building Structures and Structural Design (ITKE) at the Since 2000 Jan Knippers has been head of the Institute University of Stuttgart. He studied civil engineering and holds a for Building Structures and Structural Design (itke) at the Master of Science from the Technical University of Munich and a University of Stuttgart and involved in many research projects Bachelor of Engineering from the University of Applied Sciences on fiber based materials and biomimetics in architecture. He Biberach, Germany. His research focuses on load path adapted is also partner and co-founder of Knippers Helbig Advanced application of fiber reinforced polymers as building structures Engineering. The focus of their work is on efficient structural for architecture. design for international and architecturally demanding projects. Jan Knippers completed his Ph.D. studies of engineering at the Technical University of Berlin in 1992.

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