MicroNAS: Memory and Latency Constrained Hardware-Aware Neural Architecture Search for Time Series Classification on Microcontrollers

This paper presents MicroNAS, a system designed to automatically search and generate neural network architectures capable of classifying time series data on resource-constrained microcontrollers (MCUs) and generating standard tf-lite ML models. MicroNAS takes into account user-defined constraints on execution latency and peak memory consumption on a target MCU. This approach ensures that the resulting neural network architectures are optimised for the specific constraints and requirements of the MCU on which they are implemented. To achieve this, MicroNAS uses a look-up table estimation approach for accurate execution latency calculations, with a minimum error of only 1.02ms. This accurate latency estimation on MCUs sets it apart from other hardware-aware neural architecture search (HW-NAS) methods that use less accurate estimation techniques. Finally, MicroNAS delivers performance close to that of state-of-the-art models running on desktop computers, achieving high classification accuracies on recognised datasets (93.93% on UCI-HAR and 96.33% on SkodaR) while running on a Cortex-M4 MCU

ARMart – AR-Based Shopping Assistant to Choose and Find Store Items

Supermarkets offer a wide range of products which makes it challenging for consumers to choose between the different options and find the items they are looking for. Augmented Reality (AR) applications, however, have a high potential to enrich real-world objects with information which can be leveraged to improve this process. We developed an application that runs on a regular smartphone and helps users to choose between packaged groceries based on factors such as calories or sugar, rated on a scale from red (bad) to green (good). Compared to previous work, there is no need for a priori knowledge about product locations making the system suitable for many use cases. Moreover, information maps precisely onto the outline of the product\u27s and not on the approximate shelf. To do so, no modifications of the objects, such as specialized tags, are necessary. Additionally, users can find items just by entering the name. Highlighting the packaging virtually helps to find the desired product. It is also possible to make a binary distinction between groceries that contain specific ingredients

Design Space and Usability of Earable Prototyping

Earable computing gains growing attention within research and becomes ubiquitous in society. However, there is an emerging need for prototyping devices as critical drivers of innovation. In our work, we reviewed the features of existing earable platforms. Based on 24 publications, we characterized the design space of earable prototyping. We used the open eSense platform (6-axis IMU, auditory I/O) to evaluate the problem-based learning usability of non-experts. We collected data from 79 undergraduate students who developed 39 projects. Our questionnaire-based results suggest that the platform creates interest in the subject matter and supports self-directed learning. The projects align with the research space, indicating ease of use, but lack contributions for more challenging topics. Additionally, many projects included games not present in current research. The average SUS score of the platform was 67.0. The majority of problems are technical issues (e.g., connecting, playing music)

Brought to light: the Bcl-2 transmembrane domain interactome elucidated by a bimolecular split luciferase assay and its impact on apoptosis signalling

Apoptose ist eine Form des programmierten Zelltods, die häufig bei verschiedenen Krankheiten wie Krebs gestört ist. Ein Schlüsselereignis der Apoptose ist die Permeabilisierung der äußeren Mitochondrienmembran (MOMP), die von der B-Zell-Lymphom 2 (Bcl-2) Proteinfamilie gesteuert wird. Bcl-2-Proteine bilden ein komplexes Interaktionsnetzwerk, in dem sich pro- und anti-apoptotische Mitglieder gegenseitig zugunsten von Zelltod oder -Überleben hemmen. Das Netzwerk wird durch die Interaktion zwischen dem Bcl-2 Homologie 3 Motiv (BH3) und der hydrophoben Furche definiert. Eine neue Art von niedermolekularen Wirkstoffen, sogenannte BH3-Mimeticka, welche die hydrophobe Furche anti-apoptotischer Bcl-2 Proteine besetzen, ist wirksam in der Krebstherapie. Es verdichten sich jedoch Hinweise darauf, dass die weit weniger untersuchte C-terminale Transmembrandomäne (TMD) von Bcl-2 Proteinen, die traditionell als Membrananker fungiert, ebenfalls als Interaktionsfläche dienen kann. Zur weiteren Aufklärung der Interaktionen in der Bcl-2-Proteinfamilie über die TMD wurde ein zellbasierter Assay entwickelt und validiert, bei dem das mit TMDSequenzen fusionierte bimolekulare Luziferase-System NanoBiT mit gleichzeitiger Expression von Fluorophoren zur Signalnormalisierung kombiniert wird. Eine systematische Analyse der TMD-Interaktionen zwischen pro-apoptotischen Effektor-Bcl-2-Proteinen (BAX, BAK und BOK) und anti-apoptotischen Bcl-2-ähnlichen Proteinen (BCL-2, BCL-XL, BCL-W, MCL-1 und A1) offenbarte homotypische Interaktionen zwischen Effektor-TMDs und Interaktionen von Effektor-TMDs mit BCL-XL-TMD und BCL-W-TMD. Interessanterweise wurde eine bisher unbekannte Interaktion von BOK-TMD und BCL-2-TMD identifiziert. Die subzelluläre Lokalisierung Fluorophor-konjugierter TMD-Peptide verdeutlichte, dass einige TMDs präferentiell in Mitochondrien (BAX, BAK, BCL-XL, BCL-W) lokalisiert sind, während andere (BOK, BCL-2, MCL-1) vorwiegend mit dem endoplasmatischen Retikulum (ER) kolokalisiert sind. TMD-Austausch und Mutation in BAX bestätigten eine wichtige Rolle der BAX-TMD bei der BAX-Inhibition, während der TMD-Austausch in BAK einen vernachlässigbaren Einfluss auf die BAK-Regulierung durch BCL-2 hatte. Darüber hinaus hingen sowohl die Kolokalisierung von BOK und BCL-2 als auch die Hemmung des durch BOK-Überexpression induzierten Zelltods durch BCL-2 von den TMD Sequenzen ab. Dementsprechend modulierte TMD-Mutation von BCL-2 die Interaktion mit BOK-TMD, die subzelluläre Lokalisierung und die anti-apoptotische Kapazität von BCL-2. Letztlich steigerte die Abwesenheit von BCL-2 den BOK-abhängigen ER-Stress-induzierten Zelltod, was auf einen physiologischen Kontext für die funktionelle Bedeutung ihrer TMD-Interaktion hinweist. Somit hebt diese Arbeit hervor, dass die Aufklärung des Bcl-2-TMD-Interaktoms für unser Verständnis der Apoptose-Regulation wichtig ist und ebnet den Weg für zukünftige Untersuchungen der TMD als Ziel für klinische Interventionen

OpenEarable:Open Hardware Earable Sensing Platform

Earables are ear-worn devices that offer functionalities beyond basic audio in- and output. In this paper we present the ongoing development of a new, open-source, Arduino-based earable platform called OpenEarable. It is based on standard components, is easy to manufacture and costs roughly $40 per device at batch size ten. We present the first version of the device which is equipped with a series of sensors and actuators: a 3-axis accelerometer and gyroscope, an ear canal pressure and temperature sensor, an inward facing ultrasonic microphone as well as a speaker, a push button, and a controllable LED. We demonstrate the versatility of the prototyping platform through three different example application scenarios. In sum, OpenEarable offers a general-purpose, open sensing platform for earable research and development.<br/

Responsible, Automated Data Gathering for Timely Citizen Dashboard Provision During a Global Pandemic (COVID-19

Creating a public understanding of the dynamics of a pandemic, such as COVID-19, is vital for introducing restrictive regulations. Gathering diverse data responsibly and sharing it with experts and citizens in a timely manner is challenging. This article reviews methodologies of COVID-19 dashboard design and discusses both technical and non-technical challenges associated. Advice and lessons learned from building a citizen-focused, automated county-precision dashboard for Germany are shared. Within four months, the web-based tool had 5 million unique visitors and 70 million sessions. Three developers set up the basic version in less than one week. Early on, data was screen scraped. An iterative process improved timeliness by adding more fine-grained data sources. A collaborative online table editor enabled near real-time corrections. Alerting was setup for errors, and statistics apply for sanity checking. Static site generation and a content delivery network help to serve large user loads in a timely manner. The flexible design allowed to iteratively integrate more complex statistics based on expert knowledge built on top of the collected data and secondary data sources such as ICU beds and citizen movement

Enhancing Efficiency in HAR Models: NAS Meets Pruning

Real-time monitoring of human activities using wearable devices often requires the deployment of machine learning models on resource-constrained edge devices. State-of- the-art Human Activity Recognition models suffer from excessive size and complexity. Furthermore, our systematic analysis reveals that even worse, the computational cost and model size of most SOTA HAR models escalate significantly with increasing sensor channels. With advances in sensor technology that make it easier to scale sensor deployments that capture human activities, ad- dressing this challenge becomes critical for practical applicability. In this work, we propose an integrated neural architecture search framework to further lighten HAR models. The proposed framework simultaneously selects and reduces the number of sensor channels, prunes filters, and decreases the temporal dimensions while training the model on optimized hardware. This results in smaller and less complex models. Experiments on three HAR datasets demonstrate that our framework outperforms two state-of-the-art pruning methods in reducing model size and com- plexity, while achieving superior performance. Furthermore, we successfully applied our proposed framework to the deployment of a HAR model on a microcontroller, highlighting its feasibility for real-world implementation

EarRumble: Discreet Hands- and Eyes-Free Input by Voluntary Tensor Tympani Muscle Contraction

We explore how discreet input can be provided using the tensor tympani -a small muscle in the middle ear that some people can voluntarily contract to induce a dull rumbling sound.We investigate the prevalence and ability to control the muscle through an online questionnaire (N=192) in which 43.2% of respondents reported the ability to ear rumble. Data collected from participants (N=16) shows how in-ear barometry can be used to detect voluntary tensor tympani contraction in the sealed ear canal. This data was used to train a classifer based on three simple ear rumble gestures which achieved 95% accuracy. Finally, we evaluate the use of ear rumbling for interaction, grounded in three manual, dual-task application scenarios (N=8). This highlights the applicability of EarRumble as a low-efort and discreet eyes-and hands-free interaction technique that users found magical and almost telepathic.</p

FLECTILE: 3D-printable soft actuators for wearable computing

Rapid prototyping and fast manufacturing processes are critical drivers for implementing wearable devices. This paper shows an exemplary method for building flexible, fully elastomeric, vibrotactile electromagnetic actuators based on the Lorentz force law. This paper also introduces the design parameters required for well-functioning actuators and studies the properties of such actuators. The crucial element of the actuator is a helical planer coil manufactured from "capillary" silver TPU (Thermoplastic polyurethane), an ultra-stretchable conductor. This paper leverages the novel material to manufacture soft vibration actuators in fewer and simpler steps than previous approaches. Best practices and procedures for building a wearable actuator are reported. We show that the dimension of the actuators are easily configurable and can be printed in batch-size-one using 3D printing. Actuators can be attached directly to the skin as all the components of FLECTILE are made from biocompatible polymers. Tests on the driving properties have confirmed that the actuator could reach a broad scope of frequency up to 200 Hz with a small voltage (5 V) required. A user study showed that vibrations of the actuator are well perceivable by six study participants under an observing, hovering, and resting condition