This work describes a microcontact printing (µCP) process for reproducible manufacturing of liquid gallium alloy-based soft and stretchable electronics. One of the leading approaches to create soft and stretchable electronics involves embedding liquid metals (LM) into an elastomer matrix. Although the advantages of liquid metal-based electronics have been well established, their mainstream adoption and commercialization necessitates development of precise and scalable manufacturing methods. To address this need, a scalable µCP process is presented that uses surface-functionalized, reusable rigid, or deformable stamps to transfer eutectic gallium-indium (EGaIn) patterns onto elastomer substrates. A novel approach is developed to create the surfacefunctionalized stamps, enabling selective transfer of LM to desired locations on a substrate without residues or electrical shorts. To address the critical needs of precise and reproducible positioning, alignment, and stamping force application, a high-precision automated µCP system is designed. After describing the approach, the precision of stamps is evaluated and EGaIn features (as small as 15 µm line width), as well as electrical functionality of printed circuits with and without deformation, are fabricated. The presented process addresses many of the limitations associated with the alternative fabrication processes, and thus provides an effective approach for scalable fabrication of LM-based soft and stretchable microelectronics.tissue damage, and impairment of natural motion, thereby providing increased robustness, safety, mechanical conformability, and compliance matching with biological tissues. As such, soft and stretchable electronics could have a transformative impact in wearable technologies for personal computing and healthcare, [1] implantable electronics, [2] and soft robotics. [3,4] In recent years, many different types of soft and stretchable electronics have been developed, as outlined in two recent review papers. [1,2] One of the leading approaches to realize soft and stretchable electronic circuits involves embedding gallium-based liquid metal (LM) alloy traces at desired spatial locations within an elastomer body. [5,6] Specifically, the binary alloy of eutectic gallium-indium (EGaIn: 75 wt% Ga and 25 wt% of In) and the ternary alloy of gallium-indium-tin (Galinstan) are both liquid at room temperature: they flow freely with negligible resistance (viscosity of EGaIn is about 1.9 mPa s [7] ) and accommodate changes in channel shapes, thereby maintaining electrical circuit functionality without failure even at large strains (>100%). The electrical conductivity of gallium-based liquid metal alloys (3.4 × 10 6 S m −1 for EGaIn, [8] which is about 1/16th of copper) is orders of magnitude higher than ionic liquids and conductive elastomers. These alloys are of low toxicity [9] and have very low vapor pressure, [8] making them ideal for wearable computing and health care applications.Uniquely, when exposed to even low levels of oxygen, a few nanometer thick,...

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The amount of power that can be provided for charging the batteries of the electric vehicles connected to a single neighborhood step-down transformer is constrained by the infrastructure. This paper presents a distributed and collaborative residential-level power grid management application to alleviate the need of costly infrastructure upgrade. The application is designed to be hosted in our in-house developed network-as-automation platform (NAP) technology where most of the control functionalities may be moved onto the networking devices. Moreover, we have adapted a service-oriented software engineering principle to achieve scalability, autonomous, and architecture agnostic properties for the residential-level EV charging. We demonstrate a functional prototype where off-the-shelf networking devices capable to host a Linux Operating system are used to showcase the NAP technology. Furthermore, we developed a webbased user interface that may be accessible from any standard computing device, e.g. iPhone, to monitor the runtime operation of this application.

This paper presents a novel pipelining technique designed specifically to improve the execution of cyclic control systems and applications in terms of scan cycle time reduction and/or execution of additional workload. Based on the observation that cyclic control systems are tightly coupled with physical processes and that state information (e.g. on/off signals, temperature, pressure) is the most critical data in an application, we present new execution schemes that overlap the execution of multiple cycles in multicore processors over time. Using an edge detection application benchmark and a software real-time PLC (Programmable Logic Controller) implementation on a quad-core processor, we validate our pipelining method and show the performance scalability of the various schemes. Additionally, we analyze the resilience of our pipelining approach to time delays and propose a speculative execution method to deal with data dependency violations.