Towards Human Stress and Activity Recognition: A Review and a First Approach Based on Low-Cost Wearables

Detecting stress when performing physical activities is an interesting field that has received relatively little research interest to date. In this paper, we took a first step towards redressing this, through a comprehensive review and the design of a low-cost body area network (BAN) made of a set of wearables that allow physiological signals and human movements to be captured simultaneously. We used four different wearables: OpenBCI and three other open-hardware custom-made designs that communicate via bluetooth low energy (BLE) to an external computer—following the edge-computingconcept—hosting applications for data synchronization and storage. We obtained a large number of physiological signals (electroencephalography (EEG), electrocardiography (ECG), breathing rate (BR), electrodermal activity (EDA), and skin temperature (ST)) with which we analyzed internal states in general, but with a focus on stress. The findings show the reliability and feasibility of the proposed body area network (BAN) according to battery lifetime (greater than 15 h), packet loss rate (0% for our custom-made designs), and signal quality (signal-noise ratio (SNR) of 9.8 dB for the ECG circuit, and 61.6 dB for the EDA). Moreover, we conducted a preliminary experiment to gauge the main ECG features for stress detection during rest.

How Open Is the Maker Movement? Integrative Literature Review of the Openness Practices in the Global Maker Movement

This article explores the multiple meanings of the concept of openness in the global maker movement. Openness is viewed as one of the key principles of the maker movement. As the global maker movement is a bricolage of diverse and situated practices and traditions, there are also many different interpretations and ways of practicing openness. We have explored this diversity with an integrative literature review, relying on the Web of Science™ database. We identified three interrelated but also, in part, mutually contested approaches to openness. Firstly, openness often refers to applying open hardware. Secondly, it is in many cases related to the inclusion and empowerment of various groups in making. Thirdly, openness appears to be seen as a means to pursue economic growth through increasing innovation activity and entrepreneurship. Our results also highlight the substantial barriers encountered by makers while aiming to open up their practices. These barriers include: value conflicts in which openness is overridden by other important values; exclusion of lower income groups from making due to a lack of resources; and difficulties in maintaining long-term activities. The different meanings of openness together with the barriers create tensions within the maker movement while implementing openness. We propose that engaging in a reflexive futures dialogue on the consequences of these tensions can enhance the maker movement to become more open, inclusive and resilient.

Stimulus-induced narrow-band gamma oscillations in humans can be recorded using open-hardware low-cost EEG amplifier

Stimulus-induced narrow-band gamma oscillations (30-70 Hz) in human electro - encephalograph (EEG) have been linked to attentional and memory mechanisms and are abnormal in mental health conditions such as autism, schizophrenia and Alzheimer's Disease. This suggests that gamma oscillations could be valuable both as a research tool and an inexpensive, non-invasive biomarker for disease evaluation. However, since the absolute power in EEG decreases rapidly with increasing frequency following a "1/f" power law, and the gamma band includes line noise frequency, these oscillations are highly susceptible to instrument noise. Previous studies that recorded stimulus-induced gamma oscillations used expensive research-grade EEG amplifiers to address this issue. While low-cost EEG amplifiers have become popular in Brain Computer Interface applications that mainly rely on low-frequency oscillations (<30 Hz) or steady-state-visually-evoked-potentials, whether they can also be used to measure stimulus-induced gamma oscillations is unknown. We recorded EEG signals using a low-cost, open-source amplifier (OpenBCI) and a traditional, research-grade amplifier (Brain Products GmbH) in male (N = 6) and female (N = 5) subjects (22-29 years) while they viewed full-screen static gratings that are known to induce gamma oscillations. OpenBCI recordings showed gamma response in almost all the subjects who showed a gamma response in Brain Products recordings, and the spectral and temporal profiles of these responses in alpha (8-13 Hz) and gamma bands were highly correlated between OpenBCI and Brain Products recordings. These results suggest that low-cost amplifiers can potentially be used in stimulus induced gamma response detection, making its research, and application in medicine more accessible.

Design and Field Implementation of a Low-Cost, Open-Hardware Platform for Hydrological Monitoring

Hydrologic processes acting on catchments are complex and variable, especially in mountain basins due to their topography and specific characteristics, so runoff simulation models and water management are also complex. Nevertheless, model parameters are usually estimated on the basis of guidelines from user manuals and literature because they are not usually monitored, due to the high cost of conventional monitoring systems. Within this framework, a new and promising generation of low-cost sensors for hydrologic monitoring, logging, and transition has been developed. We aimed to design a low-cost, open-hardware platform, based on a Raspberry Pi and software written in Python 3, for measuring, recording, and wireless data transmission in hydrological monitoring contexts. Moreover, the data are linked to a runoff model, in real time, for flood prevention. Complementarily, it emphasizes the role of the calibration and validation of soil moisture, rain gauges, and water depth sensors in laboratories. It was installed in a small mountain basin. The results showed mean absolute errors of ±2.2% in soil moisture, ±1 mm in rainfall, and ±0.51 cm in water depth measurements; they highlight the potential of this platform for hydrological monitoring and flood risk management.

Opening Up The Tools For Doing Science: The Case Of The Global Open Science Hardware Movement

Open science hardware (OSH) is a term frequently used to refer to artifacts, but also to a practice, a discipline and a collective of people worldwide pushing for open access to the design of tools to produce scientific knowledge. The Global Open Science Hardware (GOSH) movement gathers actors from academia, education, the private sector and civil society advocating for OSH to be ubiquitous by 2025. This paper examines the GOSH movement’s emergence and main features through the lens of transitions theory and the grassroots innovation movements framework. GOSH is here described embedded in the context of the wider open hardware movement and analyzed in terms of framings that inform it, spaces opened up for action and strategies developed to open them. It is expected that this approach provides insights on niche development in the particular case of transitions towards more plural and democratic sociotechnical systems.

VentQsys: Low-cost open IoT system for $$CO_2$$ monitoring in classrooms

In educational context, a source of nuisance for students is carbon dioxide ($$CO_2$$ C O 2 ) concentration due to closed rooms and lack of ventilation or circulatory air. Also, in the pandemic context, ventilation in indoor environments has been proven as a good tool to control the COVID-19 infections. In this work, it is presented a low cost IoT-based open-hardware and open-software monitoring system to control ventilation, by measuring carbon dioxide ($$CO_2$$ C O 2 ), temperature and relative humidity. This system provides also support for automatic updating, auto-self calibration and adds some Cloud and Edge offloading of computational features for mapping functionalities. From the tests carried out, it is observed a good performance in terms of functionality, battery durability, compared to other measuring devices, more expensive than our proposal.

Implementación de un servicio de monitoreo y control de jardines en un municipio de Lima mediante el uso de Internet de las Cosas

El presente trabajo muestra la implementación de un sistema de monitoreo basado en tecnología Open Hardware, destinado a la gestión de jardines de un municipio de la capital peruana, usando red móvil y sensores para el manejo apropiado del agua con datos en tiempo real.