A Characterization of Actuation Techniques for Generating Movement in Shape-Changing Interfaces

Abstract This article characterizes actuation techniques for generating movement in shape-changing displays with physically reconfigurable geometry. To date, few works in Human Computer Interaction literature provide detailed and reflective descriptions of the implementation techniques used in shape-changing displays. This hinders the rapid development of novel interactions as researchers must initially spend time understanding technologies before prototyping new interactions and applications. To bridge this knowledge gap, we propose a taxonomy that classifies actuator characteristics and simplifies the process for designers to select appropriate technologies that match their requirements for developing shape-displays. We scope our investigation to linear actuators that are used in grid configurations. The taxonomy is validated by (a) examining current implementation techniques of motorized, pneumatic, hydraulic, magnetic, and shape-memory actuators in the literature, (b) constructing prototypes to address limited technical details and explore actuator capabilities in depth, (c) describing a use-case scenario through a case study that details the construction of a 10 ? 10 actuator shape-display, and (d) a set of guidelines to aid researchers in selecting actuation techniques for shape-changing applications. The significance of our taxonomy is twofold. First, we provide an original contribution that enables HCI researchers to appropriately select actuation techniques and build shape-changing applications. This is situated amongst other past works that have investigated broader application scenarios such as a shape-changing vocabulary, a framework for shape transformations, material properties, and technical characteristics of various actuators. Second, we carry out in-depth investigations to validate our taxonomy and expand the knowledge of vertical actuation in shape-changing applications to enable rapid development

LoRa for the Internet of Things

New transceiver technologies have emerged which enable power efficient communication over very long distances. Examples of such Low-Power Wide-Area Network (LPWAN)technologies are LoRa, Sigfox and Weightless. A typicalapplication scenario for these technologies is city wide meter reading collection where devices send readings at very low frequency over a long distance to a data concentrator (one-hop networks). We argue that these transceiversare potentially very useful to construct more generic Internet of Things (IoT) networks incorporating multi-hop bi-directional communication enabling sensing and actuation. Furthermore, these transceivers have interesting features notavailable with more traditional transceivers used for IoT networks which enable construction of novel protocol elements. In this paper we present a performance and capabilityanalysis of a currently available LoRa transceiver. We describe its features and then demonstrate how such transceivercan be put to use efficiently in a wide-area application scenario. In particular we demonstrate how unique featuressuch as concurrent non-destructive transmissions and carrier detection can be employed. Our deployment experiment demonstrates that 6 LoRa nodes can form a network covering 1.5 ha in a built up environment, achieving a potential lifetime of 2 year on 2 AA batteries and delivering data within 5 s and reliability of 80%

ShapeClip: towards rapid prototyping with shape-changing displays for designers

This paper presents ShapeClip: a modular tool capable of transforming any computer screen into a z-actuating shape-changing display. This enables designers to produce dynamic physical forms by "clipping" actuators onto screens. ShapeClip displays are portable, scalable, fault-tolerant, and support runtime re-arrangement. Users are not required to have knowledge of electronics or programming, and can develop motion designs with presentation software, image editors, or web-technologies. To evaluate ShapeClip we carried out a full-day workshop with expert designers. Participants were asked to generate shape-changing designs and then construct them using ShapeClip. ShapeClip enabled participants to rapidly and successfully transform their ideas into functional systems

Estimating node lifetime in interference environments

For commercial Wireless Sensor Network (WSNs) deployments it is necessary to estimate the network lifetime. It must be possible before network deployment to determine how long a network maintains operational before maintenance is required and batteries have to be replaced. Unfortunately, node lifetime is very dependent on the radio environment in which the node is operated. As we will demonstrate in this paper the node lifetime in a very busy radio environment can be up to 11 times shorter than in a quiet environment. WSNs employ duty-cycled communication protocols where receivers periodically sample the channel to determine if it has to remain active to receive a message. Radio interference triggers the receive mechanism causing an unnecessary wake-up which leads to an increase in a node’s energy consumption. In this paper we present a method for estimating node energy consumption in a target radio environment. We describe how to capture the essential characteristics of the radio environment and how to use this information to predict node lifetime. We demonstrate the usability of the proposed method using the well known WSN communication protocol ContikiMAC. Our evaluation comprising real-world scenarios shows that the proposed method is able to accurately predict node lifetime

It bends but would it break?:topological analysis of BGP infrastructures in Europe

The Internet is often thought to be a model of resilience, due to a decentralised, organically-grown architecture. This paper puts this perception into perspective through the results of a security analysis of the Border Gateway Protocol (BGP) routing infrastructure. BGP is a fundamental Internet protocol and its intrinsic fragilities have been highlighted extensively in the literature. A seldom studied aspect is how robust the BGP infrastructure actually is as a result of nearly three decades of perpetual growth. Although global black-outs seem unlikely, local security events raise growing concerns on the robustness of the backbone. In order to better protect this critical infrastructure, it is crucial to understand its topology in the context of the weaknesses of BGP and to identify possible security scenarios. Firstly, we establish a comprehensive threat model that classifies main attack vectors, including but non limited to BGP vulnerabilities. We then construct maps of the European BGP backbone based on publicly available routing data. We analyse the topology of the backbone and establish several disruption scenarios that highlight the possible consequences of different types of attacks, for different attack capabilities. We also discuss existing mitigation and recovery strategies, and we propose improvements to enhance the robustness and resilience of the backbone. To our knowledge, this study is the first to combine a comprehensive threat analysis of BGP infrastructures withadvanced network topology considerations. We find that the BGP infrastructure is at higher risk than already understood, due to topologies that remain vulnerable to certain targeted attacks as a result of organic deployment over the years. Significant parts of the system are still uncharted territory, which warrants further investigation in this direction

Introducing Classroom Cloudlet : a mobile, tangible, and transparent approach to Internet of Things education

Providing a good understanding to children and educators on the Internet of Things (IoT) means to make them aware about where the data goes, how it is stored, and what it is stored on. In this perspective many commercial IoT systems have been shown to be unsuitable for this purpose especially when used in an educational context. They do not create user centric data collection opportunities; many of their IoT sensors that send data offsite to an online cloud create gaps in knowledge; the sensors themselves are not transparent: it's not clear what data they are collecting and how, and they are not easily compatible with school networks. Classroom Cloudlet addresses this issue. This demonstration presents an end-to-end IoT like system that includes a mobile, tangible, and transparent classroom cloudlet. Classroom Cloudlet aims to allow data from multiple devices to be easily shared, collated and analysed without using the Internet, but while still educating students about IoT and cloud concepts. The classroom cloudlet aims to be a physical representation of a cloud in an IoT system; visualise the movement of data around the system; provide a web front-end for students to view and create custom visualisations of their data. Classroom Cloudlet aims to gives the educator and the children full control and ownership of their data

Basic Cyber Hygiene:Does It Work?

A number of security certifications for small- and medium-size enterprises have been proposed, but how effective are these schemes? We evaluated the effectiveness of Cyber Essentials and found that its security controls work well to mitigate threats that exploit vulnerabilities remotely with commodity-level tools

The Church of England and same sex marriage: beyond a rights-based analysis

Some scholars, faced with the apparent conflict between the Church of England’s teaching on marriage and the idea of equal marriage embraced by the Marriage (Same Sex Couples) Act 2013, have focussed on the implications of that Act for the constitutional relationship between church, state and nation. More frequently, academics have, noting the position of the Church of England under that Act, critiqued the legislation as an exercise in balancing competing human rights. This article by contrast, leaving behind a tendency to treat religion as a monolithic ‘other’, and leaving behind the neat binaries of rights-based analyses, interrogates the internal agonies of the Church of England as it has striven to negotiate an institutional response to the secular legalisation of same sex marriage. It explores the struggles of the Church to do so in a manner which holds in balance a wide array of doctrinal positions and the demands of mission, pastoral care and the continued apostolic identity of the Church of England

An ICT Architecture for Enabling Ancillary Services in Distributed Renewable Energy Sources Based on the SGAM Framework

Abstract: Smart Grids are electrical grids that require a decentralised way of controlling electric power conditioning and thereby control the production and distribution of energy. Yet, the integration of Distributed Renewable Energy Sources (DRESs) in the Smart Grid introduces new challenges with regards to electrical grid balancing and storing of electrical energy, as well as additional monetary costs. Furthermore, the future smart grid also has to take over the provision of Ancillary Services (ASs). In this paper, a distributed ICT infrastructure to solve such challenges, specifically related to ASs in future Smart Grids, is described. The proposed infrastructure is developed on the basis of the Smart Grid Architecture Model (SGAM) framework, which is defined by the European Commission in Smart Grid Mandate M/490. A testbed that provides a flexible, secure, and low-cost version of this architecture, illustrating the separation of systems and responsibilities, and supporting both emulated DRESs and real hardware has been developed. The resulting system supports the integration of a variety of DRESs with a secure two-way communication channel between the monitoring and controlling components. It assists in the analysis of various inter-operabilities and in the verification of eventual system designs. To validate the system design, the mapping of the proposed architecture to the testbed is presented. Further work will help improve the architecture in two directions; first, by investigating specific-purpose use cases, instantiated using this more generic framework; and second, by investigating the effects a realistic number and variety of connected devices within different grid configurations has on the testbed infrastructure