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Abstract Unmanned Aerial Vehicles (UAVs) hold immense potential across various fields, including precision agriculture, rescue missions, delivery services, weather monitoring, and many more. Despite this promise, the limited flight duration of the current UAVs stands as a significant obstacle to their broadscale deployment. Attempting to extend flight time by solar panel charging during midflight is not viable due to battery limitations and the eventual need for replacement. This paper details our investigation of a battery-free fixed-wing UAV, built from cost-effective off-the-shelf components, that takes off, remains airborne, and lands safely using only solar energy. In particular, we perform a comprehensive analysis and design space exploration in the contemporary solar harvesting context and provide a detailed accounting of the prototype’s mechanical and electrical capabilities. We also derive the Greedy Energy-Aware Control (GEAC) and Predictive Energy-Aware Control (PEAC) solar control algorithm that overcomes power system brownouts and total-loss-of-thrust events, enabling the prototype to perform maneuvers without a battery. Next, we evaluate the developed prototype in a bench-top setting using artificial light to demonstrate the feasibility of batteryless flight, followed by testing in an outdoor setting using natural light. Finally, we analyze the potential for scaling up the evaluation of batteryless UAVs across multiple locations and report our findings. 

The limited and highly variable resource dynamics of underserved communities, each with their own unique needs and values, underscore the need to integrate a context-aware approach when designing for these settings. Context-aware computing has long been a fundamental aspect of ubiquitous and pervasive systems, yet its application in Information and Communication Technologies for Development (ICT4D) remains limited. Existing context-aware approaches are predominantly designed for resource-rich environments and privileged communities, often failing to account for the unique constraints and dynamics of underserved populations. In this paper, we advocate for a paradigm shift in ICT system and service design to serve not only the privileged but also the underserved. Through the lens of two real-world case studies, we illustrate the contextual challenges faced by underserved communities and validate the design goals of our proposed framework by grounding them in real-world constraints, needs, and potential outcomes. Drawing upon existing literature and insights from the case studies, we first redefine context in ICT4D as a dynamic interplay of situated location, community needs, and limited resources, emphasizing a community-centered perspective. Building upon this definition, we conceptualize a more community-context-aware ICT4D design and propose enabling technologies for integrating community-in-the-loop methodologies, efficient resource allocation mechanisms, and context-aware service resiliency and adaptability strategies to enhance ICT services in resource-limited settings. By introducing a more context-aware approach to ICT4D, this paper aims to foster inclusivity, mitigate information inequity, and contribute to bridging the digital divide. Our work lays the foundation for future research on inclusive, resource-efficient, and community-driven context-aware ICT solutions. 

We introduce DissolvPCB, an electronic prototyping technique for fabricating fully recyclable printed circuit board assemblies (PCBAs) using affordable FDM 3D printing, with polyvinyl alcohol (PVA) as a water-soluble substrate and eutectic gallium-indium (EGaIn) as the conductive material. When obsolete, the PCBA can be easily recycled by immersing it in water: the PVA dissolves, the EGaIn re-forms into a liquid metal bead, and the electronic components are recovered. These materials can then be reused to fabricate a new PCBA. We present the DissolvPCB workflow, characterize its design parameters, evaluate the performance of circuits produced with it, and quantify its environmental impact through a lifecycle assessment (LCA) comparing it to conventional CNC-milled FR-4 boards. We further develop a software plugin that automatically converts PCB design files into 3D-printable circuit substrate models. To demonstrate the capabilities of DissolvPCB, we fabricate and recycle three functional prototypes: a Bluetooth speaker featuring a double-sided PCB, a finger fidget toy with a 3D circuit topology, and a shape-changing gripper enabled by Joule-heat-driven 4D printing. The paper concludes with a discussion of current technical limitations and opportunities for future directions. 

The carbon emissions of modern information and communication technologies (ICT) present a significant environmental challenge, accounting for approximately 4% of global greenhouse gases, and are on par with the aviation industry. Modern internet services levy high carbon emissions due to the significant infrastructure resources required to operate them, owing to strict service requirements expected by users. One opportunity to reduce emissions is relaxing strict service requirements by leveraging eco-feedback. In this study, we explore the effect of the carbon reduction impact of allowing longer internet service response time based on user preferences and feedback. Across four services (i.e., Amazon, Google, ChatGPT, Social Media) our study reveals opportunities to relax latency requirements of services based on user feedback; this feedback is application-specific, with ChatGPT having the most favorable eco-feedback tradeoff. Further system studies suggest leveraging the reduced latency can bring down the carbon footprint of an average service request by 93.1%. 

Exploring the shared, intersectional problem space of empowered users making carbon-aware decisions that guide computer systems operation. 

We present BIOGEM, a fully biodegradable McKibben actuator with integrated sensing, made from gelatin-based composites. By tailoring the material compositions, we customize the mechanical and electrical properties of the biodegradable composites, creating an integrated biodegradable system that combines both actuation and sensing functionalities. BIOGEM integrates a McKibben actuating structure by using stiff gelatin as outer braiding and the stretchable gelatin as air chambers. It also integrates resistive strain sensing through ionic gelatin, allowing the actuator to monitor its own deformation without relying on conventional electronics. We characterize the actuator’s performance across key parameters including braid angle, wall thickness, and material stiffness, demonstrating reliable contraction and repeatable force output at low pressures. Biodegradation is validated through both enzyme-assisted and backyard soil studies, confirming the material’s sustainable end-of-life behavior under realistic conditions. We illustrate the potential of this platform through interactive, edible, and environmentally-degradable prototypes across human–computer interaction and soft robotics scenarios. 

As edge devices see increasing adoption across a wide range of applications, understanding their environmental impact has become increasingly urgent. Unlike cloud systems, edge deployments consist of tightly integrated microcontrollers, sensors, and energy sources that collectively shape their carbon footprint. In this paper, we present a carbon-aware design framework tailored to embedded edge systems. We analyze the embodied emissions of several off-the-shelf microcontroller boards and peripheral components and examine how deployment context—such as workload type, power source, and usage duration—alters the carbon-optimal configuration. Through empirical case studies comparing battery- and solar-powered scenarios, we find that the lowest-emission choice is often workload- and context-specific, challenging assumptions that energy-efficient or renewable powered systems are always the most sustainable. Our results highlight the need for fine-grained, system-level reasoning when designing for sustainability at the edge and provide actionable insights for researchers and practitioners seeking to reduce the carbon cost of future deployments. 

In the pursuit of place-based, generative AI educational technologies, the field of Human-Computer Interaction (HCI) offers a powerful framework for identifying and addressing diverse user needs. In partnership an Hawaiian language immersion (Kaiapuni) school and 13 educators, this 1-year case study presents a research approach rooted in assets-based design and Design Thinking that leverages rapid iteration, usability testing, and speculative prototyping to co-design a generative AI tool for Kaiapuni educators. Our synthesis of observations, participant reflections, and usability testing feedback provides evidence for such methods in their ability to envision ideal outcomes for Kaiapuni education supported by generative AI technologies. 

Manoomin, the Ojibwe word for Northern Wild Rice, is a culturally significant food source native to the Western Great Lakes region of North America. For generations, Manoomin stewardship has been central to Ojibwe culture and identity, harvested using traditional methods which respect and enrich its growth. Recent years have shown a decline in Manoomin’s natural occurrence due to land-use change and global warming. As part of a broader conservation effort, our team has collaborated with Tribal partners to build Makak, a low-cost microclimate sensor that monitors factors affecting wild rice to support Tribal sovereignty. This article details our co-design and pilot deployment in collaboration with four partner organizations. Through this work, we share our experiences, and lessons learned from the co-design process with Tribal partners. With this work, we aim to provide insights to other projects that promote Indigenous-centric participatory, collaborative design methods for conservation and environmental sustainability. 

Current environmental challenges have profound local consequences and often benefit from the collection of fine-grained microclimate data. Advances in wireless sensor networks and the Internet of Things have led to technologies nominally suited to support remote sensing; however, in practice long-running deployments of in-field environmental sensors are rare. Field conditions are often remote and culturally sensitive, with limited power, Internet, transportation, and human infrastructure; advances in device technology alone will not suffice. We ask how communities, Internet of Things researchers, government, and other interested parties can work together to co-design useful, low burden, sustainability-focused infrastructure. Toward this end, we conducted 11 semi-structured interviews with 13 experts who use or rely on environmental sensing technology. To complement our interview data, we engaged in three months of participant observation while immersed in organizations specifically working toward manoomin (wild rice) conservation. We make two primary contributions. First, we confirm and enrich a five-stage model, the microclimate sensor lifecycle, focusing on desired features and persistent challenges. Second, we outline a space for co-design of microclimate sensors with emphasis on the cost of experience, the generally unaddressed issue of technical usability in the messy field, and the opportunity for community engagement to improve technical design and outcomes. Furthermore, we discuss future design opportunities, recommendations, and challenges in the microclimate sensor design, deployment, and sustainability space.