PickCells: A Physically Reconfigurable Cell-composed Touchscreen

Touchscreens are the predominant medium for interactions with digital services; however, their current fixed form factor narrows the scope for rich physical interactions by limiting interaction possibilities to a single, planar surface. In this paper we introduce the concept of PickCells, a fully reconfigurable device concept composed of cells, that breaks the mould of rigid screens and explores a modular system that affords rich sets of tangible interactions and novel acrossdevice relationships. Through a series of co-design activities – involving HCI experts and potential end-users of such systems – we synthesised a design space aimed at inspiring future research, giving researchers and designers a framework in which to explore modular screen interactions. The design space we propose unifies existing works on modular touch surfaces under a general framework and broadens horizons by opening up unexplored spaces providing new interaction possibilities. In this paper, we present the PickCells concept, a design space of modular touch surfaces, and propose a toolkit for quick scenario prototyping

Compliant rolling-contact architected materials for shape reconfigurability.

Architected materials can achieve impressive shape-changing capabilities according to how their microarchitecture is engineered. Here we introduce an approach for dramatically advancing such capabilities by utilizing wrapped flexure straps to guide the rolling motions of tightly packed micro-cams that constitute the material's microarchitecture. This approach enables high shape-morphing versatility and extreme ranges of deformation without accruing appreciable increases in strain energy or internal stress. Two-dimensional and three-dimensional macroscale prototypes are demonstrated, and the analytical theory necessary to design the proposed materials is provided and packaged as a software tool. An approach that combines two-photon stereolithography and scanning holographic optical tweezers is demonstrated to enable the fabrication of the proposed materials at their intended microscale

Bio-inspired Tensegrity Soft Modular Robots

In this paper, we introduce a design principle to develop novel soft modular robots based on tensegrity structures and inspired by the cytoskeleton of living cells. We describe a novel strategy to realize tensegrity structures using planar manufacturing techniques, such as 3D printing. We use this strategy to develop icosahedron tensegrity structures with programmable variable stiffness that can deform in a three-dimensional space. We also describe a tendon-driven contraction mechanism to actively control the deformation of the tensegrity mod-ules. Finally, we validate the approach in a modular locomotory worm as a proof of concept.Comment: 12 pages, 7 figures, submitted to Living Machine conference 201

Reconfigurable Antennas Using Liquid Crystalline Elastomers

This dissertation demonstrates the design of reversibly self-morphing novel liquid crystalline elastomer (LCE) antennas that can dynamically change electromagnetic performance in response to temperature. This change in performance can be achieved by programming the shape change of stimuli-responsive (i.e., temperature-responsive) LCEs, and using these materials as substrates for reconfigurable antennas. Existing reconfigurable antennas rely on external circuitry such as Micro-Electro-Mechanical-Systems (MEMS) switches, pin diodes, and shape memory alloys (SMAs) to reconfigure their performance. Antennas using MEMS or diodes exhibit low efficiency due to the losses from these components. Also, antennas based on SMAs can change their performance only once as SMAs response to the stimuli and is not reversible. Flexible electronics are capable of morphing from one shape to another using various techniques, such as liquid metals, hydrogels, and shape memory polymers. LCE antennas can reconfigure their electromagnetic performance, (e.g., frequency of operation, polarization, and radiation pattern) and enable passive (i.e., battery-less) temperature sensing and monitoring applications, such as passive radio frequency identification device (RFID) sensing tags. Limited previous work has been performed on shape-changing antenna structures based on LCEs. To date, self-morphing flexible electronics, including antennas, which rely on stimuli-responsive LCEs that reversibly change shape in response to temperature changes, have not been previously explored. Here, LCE antennas will be studied and developed. Also, the metallization of LCEs with different metal conductors and their fabrication process, by either electron beam (E-Beam) evaporation or optical gluing of the metal film will be observed. The LCE material can have a significant impact on sensing applications due to its reversible actuation that can enable a sensor to work repeatedly. This interdisciplinary research (material polymer science and electrical engineering) is expected to contribute to the development of morphing electronics, including sensors, passive antennas, arrays, and frequency selective surfaces (FSS)

Analysis, design, and implementation of a reconfigurable fractal volumetric left-handed metamaterial

At the present time, one of the greatest goals to exploit the advantages of Volumetric Left-handed Metamaterials (LHM) is overcoming their very narrow operational bandwidth. This thesis proposes two schemes to efficiently solve this difficulty: 1) a mechanism which reconfigures, at will, the frequency the LHM operates at, and 2) a novel arrangement of Split Ring Resonators (SRR) based on the Sierpi\u0144ski carpet fractal pattern with two SRR sizes. Reconfigurability is implemented by cutting two splits of different widths in each ring of the SRRs. These SRRs are simulated with switches in the ON and OFF states inside an ideal simulation environment implemented in the electromagnetic modeling software HFSS where the reflection and transmission coefficients are calculated. Through simulations, each size of SRR is independently optimized and shown to have a broad frequency range where its resonance can be selected from. The two SRRs are subsequently combined in a single structure according to the Sierpi\u0144ski carpet fractal pattern. This structure is simulated again to obtain a new frequency response with two resonance frequencies near each other. A thin-wire structure is designed and coalesced with the fractal structure which results in a LHM with two transmission bands. Finally, prototypes are fabricated by mechanically etching high-frequency laminates, and tested using standard techniques. Experimental results demonstrate that the fabricated LHM is characterized by two well-defined left-handed transmission bands. Both experimental and theoretical results show a good agreement in predicting the resonances of the complex LHM structure

A virtual dual-level reconfigurable additive manufacturing system for digital object fabrication

This paper proposes a virtual dual-level reconfigurable additive manufacturing system (DRAMS) for simulation and verification of deposition strategies in digital fabrication of product prototypes. The DRAMS is aimed to improve additive manufacturing (AM) processes with the concept of system reconfiguration. It consists of adaptable support and manipulation modules for deposition of fabrication materials. Topologies are investigated to determine the structures of these modules, and methods are developed to evaluate and optimize the system configuration. Simulations show that the DRAMS can not only handle prototypes of different sizes and fabrication materials, but also increase the process speed. The DRAMS offers an effective tool for simulation, verification and optimization of deposition strategies under different system configurations to improve process performance.postprintThe 21st Annual International Solid Freeform Fabrication (SFF) Symposium: An Additive Manufacturing Conference, Austin, TX., 9-11 August 2010. In Proceedings of the 21st International SFF Symposium, 2010, p. 266-27

Design of Reconfigurable Intelligent Surfaces for Wireless Communication: A Review

Existing literature reviews predominantly focus on the theoretical aspects of reconfigurable intelligent surfaces (RISs), such as algorithms and models, while neglecting a thorough examination of the associated hardware components. To bridge this gap, this research paper presents a comprehensive overview of the hardware structure of RISs. The paper provides a classification of RIS cell designs and prototype systems, offering insights into the diverse configurations and functionalities. Moreover, the study explores potential future directions for RIS development. Notably, a novel RIS prototype design is introduced, which integrates seamlessly with a communication system for performance evaluation through signal gain and image formation experiments. The results demonstrate the significant potential of RISs in enhancing communication quality within signal blind zones and facilitating effective radio wave imaging