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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%. 

Human studies often rely on wearable lifelogging cameras that capture videos of individuals and their surroundings to aid in visual confirmation or recollection of daily activities like eating, drinking, and smoking. However, this may include private or sensitive information that may cause some users to refrain from using such monitoring devices. Also, short battery lifetime and large form factors reduce applicability for long-term capture of human activity. Solving this triad of interconnected problems is challenging due to wearable embedded systems’ energy, memory, and computing constraints. Inspired by this critical use case and the unique design problem, we developed NIR-sighted, an architecture for wearable video cameras that navigates this design space via three key ideas: (i) reduce storage and enhance privacy by discarding masked pixels and frames, (ii) enable programmers to generate effective masks with low computational overhead, and (iii) enable the use of small MCUs by moving masking and compression off-chip. Combined together in an end-to-end system, NIR-sighted’s masking capabilities and off-chip compression hardware shrinks systems, stores less data, and enables programmer-defined obfuscation to yield privacy enhancement. The user’s privacy is enhanced significantly as nowhere in the pipeline is any part of the image stored before it is obfuscated. We design a wearable camera called NIR-sightedCam based on this architecture; it is compact and can record IR and grayscale video at 16 and 20+ fps, respectively, for 26 hours nonstop (59 hours with IR disabled) at a fraction of comparable platforms power draw. NIR-sightedCam includes a low-power Field Programmable Gate Array that implements our mJPEG compress/obfuscate hardware, Blindspot. We additionally show the potential for privacy-enhancing function and clinical utility via an in-lab eating study, validated by a nutritionist. 

Batteryless wearables use energy harvested from the environment, eliminating the burden of charging or replacing batteries. This makes them convenient and environmentally friendly. However, these benefits come at a price. Batteryless wearables operate intermittently (based on energy availability), which adds complexity to their design and introduces usability limitations not present in their battery-powered counterparts. In this paper, we conduct a scenario-based study with 400 wearable users to explore how users perceive the inherent trade-offs of batteryless wearable devices. Our results reveal users’ concerns, expectations, and preferences when transitioning from battery-powered to batteryless wearable use. We discuss how the findings of this study can inform the design of usable batteryless wearables. 

The time for battery-free computing is now. Lithium mining depletes and pollutes local water supplies and dead batteries in landfills leak toxic metals into the ground. Battery-free devices represent a probable future for sustainable ubiquitous computing and we will need many more new devices and programmers to bring that future into reality. Yet, energy harvesting and battery-free devices that frequently fail are challenging to program. The maker movement has organically developed a considerable variety of platforms to prototype and program ubiquitous sensing and computing devices, but only a few have been modified to be usable with energy harvesting and to hide those pesky power failures that are the norm from variable energy availability (platforms like Microsoft's Makecode and AdaFruit's CircuitPython). Many platforms, especially Arduino (the first and most famous maker platform), do not support energy harvesting devices and intermittent computing. To bridge this gap and lay a strong foundation for potential new platforms for maker programming, we build a tool called BOOTHAMMER: a lightweight assembly re-writer for ARM Thumb. BOOTHAMMER analyzes and rewrites the low-level assembly to insert careful checkpoint and restore operations to enable programs to persist through power failures. The approach is easily insertable in existing toolchains and is general-purpose enough to be resilient to future platforms and devices/chipsets. We close the loop with the user by designing a small set of program annotations that any maker coder can use to provide extra information to this low-level tool that will significantly increase checkpoint efficiency and resolution. These optional extensions represent a way to include the user in decision-making about energy harvesting while ensuring the tool supports existing platforms. We conduct an extensive evaluation using various program benchmarks with Arduino as our chosen evaluation platform. We also demonstrate the usability of this approach by evaluating BOOTHAMMER with a user study and show that makers feel very confident in their ability to write intermittent computing programs using this tool. With this new tool, we enable maker hardware and software for sustainable, energy-harvesting-based computing for all. 

Communication presents a critical challenge for emerging intermittently powered batteryless sensors. Batteryless devices that operate entirely on harvested energy often experience frequent, unpredictable power outages and have trouble keeping time accurately. Consequently, effective communication using today’s low-power wireless network standards and protocols becomes difficult, particularly because existing standards are usually designed to support reliably powered devices with predictable node availability and accurate timekeeping capabilities for connection and congestion management. In this article, we present Greentooth, a robust and energy-efficient wireless communication protocol for intermittently powered sensor networks. It enables reliable communication between a receiver and multiple batteryless sensors using Time Division Multiple Access–style scheduling and low-power wake-up radios for synchronization. Greentooth employs lightweight and energy-efficient connections that are resilient to transient power outages, while significantly improving network reliability, throughput, and energy efficiency of both the battery-free sensor nodes and the receiver—which could be untethered and energy constrained. We evaluate Greentooth using a custom-built batteryless sensor prototype on synthetic and real-world energy traces recorded from different locations in a garden across different times of the day. Results show that Greentooth achieves 73% and 283% more throughput compared to Asynchronous Wake-up on Demand MAC and Receiver-Initiated Consecutive Packet Transmission Wake-up Radios, respectively, under intermittent ambient solar energy and over 2× longer receiver lifetime. 

Hawaiian bilingual language immersion (Kaiapuni) schools infuse curricula with place-based education to increase student connection to culture. However, stand-in teachers often lack the background and tools needed to support immersion learning, resulting in discontinuity for students in their culturally relevant education. This experience report describes a partnership between the Ka Moamoa Lab at the Georgia Institute of Technology and Ke Kula Kaiapuni 'O Pu'ohala School to design a teacher-substitute support platform via a hybrid of assets-based design methodology and emerging technology capabilities. We share insights offered by teachers and design requirements for such a platform. We also reflect on how HCI methodologies should adapt to center and respect Native Hawaiian perspectives. 

This article calls for careful, calculated, community-driven co-design of mobile and ubiquitous solutions to bridge the gap in financing and capacity of marginalized communities as they battle for the safety and health of their members. Communities across the globe face incredible challenges to preserve their environment, lifestyle, prosperity, equality, and even democracy. In the past five years, the urgency of multiple global crises, including climate degradation that causes extreme weather and shatters ecosystems and the COVID-19 pandemic that caused a global health crisis and economic upheaval, has threatened an already delicate balance. However, the impacts of these events are uneven - vulnerable, low-income, and marginalized communities have borne the brunt of many of these crises, not having the infrastructure or capacity to address every single gap. 

Background Mobile health (mHealth) wearable devices are increasingly being adopted by individuals to help manage and monitor physiological signals. However, the current state of wearables does not consider the needs of racially minoritized low–socioeconomic status (SES) communities regarding usability, accessibility, and price. This is a critical issue that necessitates immediate attention and resolution. Objective This study’s aims were 3-fold, to (1) understand how members of minoritized low-SES communities perceive current mHealth wearable devices, (2) identify the barriers and facilitators toward adoption, and (3) articulate design requirements for future wearable devices to enable equitable access for these communities. Methods We performed semistructured interviews with low-SES Hispanic or Latine adults (N=19) from 2 metropolitan cities in the Midwest and West Coast of the United States. Participants were asked questions about how they perceive wearables, what are the current benefits and barriers toward use, and what features they would like to see in future wearable devices. Common themes were identified and analyzed through an exploratory qualitative approach. Results Through qualitative analysis, we identified 4 main themes. Participants’ perceptions of wearable devices were strongly influenced by their COVID-19 experiences. Hence, the first theme was related to the impact of COVID-19 on the community, and how this resulted in a significant increase in interest in wearables. The second theme highlights the challenges faced in obtaining adequate health resources and how this further motivated participants’ interest in health wearables. The third theme focuses on a general distrust in health care infrastructure and systems and how these challenges are motivating a need for wearables. Lastly, participants emphasized the pressing need for community-driven design of wearable technologies. Conclusions The findings from this study reveal that participants from underserved communities are showing emerging interest in using health wearables due to the COVID-19 pandemic and health care access issues. Yet, the needs of these individuals have been excluded from the design and development of current devices. 

Batteryless, energy-harvesting systems could reshape the Internet of Things into a more sustainable societal infrastructure.