Multimodal feedback for mid-air gestures when driving

Mid-air gestures in cars are being used by an increasing number of drivers on the road. Us-ability concerns mean good feedback is important, but a balance needs to be found between supporting interaction and reducing distraction in an already demanding environment. Visual feedback is most commonly used, but takes visual attention away from driving. This thesis investigates novel non-visual alternatives to support the driver during mid-air gesture interaction: Cutaneous Push, Peripheral Lights, and Ultrasound feedback. These modalities lack the expressive capabilities of high resolution screens, but are intended to allow drivers to focus on the driving task. A new form of haptic feedback — Cutaneous Push — was defined. Six solenoids were embedded along the rim of the steering wheel, creating three bumps under each palm. Studies 1, 2, and 3 investigated the efficacy of novel static and dynamic Cutaneous Push patterns, and their impact on driving performance. In simulated driving studies, the cutaneous patterns were tested. The results showed pattern identification rates of up to 81.3% for static patterns and 73.5% for dynamic patterns and 100% recognition of directional cues. Cutaneous Push notifications did not impact driving behaviour nor workload and showed very high user acceptance. Cutaneous Push patterns have the potential to make driving safer by providing non-visual and instantaneous messages, for example to indicate an approaching cyclist or obstacle. Studies 4 & 5 looked at novel uni- and bimodal feedback combinations of Visual, Auditory, Cutaneous Push, and Peripheral Lights for mid-air gestures and found that non-visual feedback modalities, especially when combined bimodally, offered just as much support for interaction without negatively affecting driving performance, visual attention and cognitive demand. These results provide compelling support for using non-visual feedback from in-car systems, supporting input whilst letting drivers focus on driving.Studies 6 & 7 investigated the above bimodal combinations as well as uni- and bimodal Ultrasound feedback during the Lane Change Task to assess the impact of gesturing and feedback modality on car control during more challenging driving. The results of study Seven suggests that Visual and Ultrasound feedback are not appropriate for in-car usage,unless combined multimodally. If Ultrasound is used unimodally it is more useful in a binary scenario.Findings from Studies 5, 6, and 7 suggest that multimodal feedback significantly reduces eyes-off-the-road time compared to Visual feedback without compromising driving performance or perceived user workload, thus it can potentially reduce crash risks. Novel design recommendations for providing feedback during mid-air gesture interaction in cars are provided, informed by the experiment findings

Novel active sweat pores based liveness detection techniques for fingerprint biometrics

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Liveness detection in automatic fingerprint identification systems (AFIS) is an issue which still prevents its use in many unsupervised security applications. In the last decade, various hardware and software solutions for the detection of liveness from fingerprints have been proposed by academic research groups. However, the proposed methods have not yet been practically implemented with existing AFIS. A large amount of research is needed before commercial AFIS can be implemented. In this research, novel active pore based liveness detection methods were proposed for AFIS. These novel methods are based on the detection of active pores on fingertip ridges, and the measurement of ionic activity in the sweat fluid that appears at the openings of active pores. The literature is critically reviewed in terms of liveness detection issues. Existing fingerprint technology, and hardware and software solutions proposed for liveness detection are also examined. A comparative study has been completed on the commercially and specifically collected fingerprint databases, and it was concluded that images in these datasets do not contained any visible evidence of liveness. They were used to test various algorithms developed for liveness detection; however, to implement proper liveness detection in fingerprint systems a new database with fine details of fingertips is needed. Therefore a new high resolution Brunel Fingerprint Biometric Database (B-FBDB) was captured and collected for this novel liveness detection research. The first proposed novel liveness detection method is a High Pass Correlation Filtering Algorithm (HCFA). This image processing algorithm has been developed in Matlab and tested on B-FBDB dataset images. The results of the HCFA algorithm have proved the idea behind the research, as they successfully demonstrated the clear possibility of liveness detection by active pore detection from high resolution images. The second novel liveness detection method is based on the experimental evidence. This method explains liveness detection by measuring the ionic activities above the sample of ionic sweat fluid. A Micro Needle Electrode (MNE) based setup was used in this experiment to measure the ionic activities. In results, 5.9 pC to 6.5 pC charges were detected with ten NME positions (50μm to 360 μm) above the surface of ionic sweat fluid. These measurements are also a proof of liveness from active fingertip pores, and this technique can be used in the future to implement liveness detection solutions. The interaction of NME and ionic fluid was modelled in COMSOL multiphysics, and the effect of electric field variations on NME was recorded at 5μm -360μm positions above the ionic fluid.This study is funded by the University of Sindh, Jamshoro, Pakistan and the Higher Education Commission of Pakistan

Development of Solid Sampling Modalities for the Liquid-Sampling Atmospheric Pressure Glow Discharge Microplasma

Fast pretreatment of samples, low resource consumption, and high analytical throughput makes direct solid sampling techniques an attractive choice for a wide range of applications. Currently there are a plethora of analytical techniques capable of solid sampling. However, no commercial technique is available that is capable of taking advantage of the key concepts of solid samplings. General disadvantages amongst the current solid sampling instrumentation are high cost of operation, limited analyte choice, and reduced analytical performance. In that regard, it is important to develop a source that has low operation cost as well as the capability to analyze a diversity of analytes. An added benefit would be if the source is comparable in analytical performance to that of solution based instruments. One potential source is the liquid sampling – atmospheric pressure glow discharge (LS-APGD) microplasma that is utilized primarily for solution analysis. The analytical merits of the LS-APGD overlaps with that of direct solid sampling. The LS-APGD provides a multi-faceted approach to analytical instruments by providing a variety of information from a compact ionization/excitation source. Unique amongst the tools in the analytical toolbox, the LS-APGD is capable of not only ionizing elements but also molecular species. Beyond that, the LS-APGD also operate in a total consumption mode, i.e no solvent waste, with solution flow rates under 100 µL min-1 as well as less than 1.0 L min-1 of helium gas flow. These analytical merits of low cost and abundance of information coincide with the key advantages of direct solid sampling. Presented in this dissertation is efforts on adding and improving solid sampling modalities to this ionization/excitation source. The dissertation discusses the influence of plasma parameters on optical emission though ambient desorption as well as the implication of those trends on underlying mechanism. On the sample preparation side, an effective means of preparing residues for analysis via intelligent substrate choice as well as co-adding dopant is provided. Finally, two sampling methods coupled to the LS-APGD is described. A novel solvent extraction method for heat sensitive samples as well as coupling to a laser ablation system for comprehensive atomic, molecular, and spatial analysis

Portable Laser-Induced Breakdown Spectroscopy for Nuclear Forensics Applications

This work demonstrates the capability of a readily available, and portable Laser Induced Breakdown Spectroscopy (LIBS) systems to conduct field screening of samples with nuclear forensics interest.A hand-held device for laser-induced breakdown spectroscopy has been investigated for the determination of uranyl fluoride surface contamination. This research demonstrates the ability to successfully detect uranium on surfaces when using a low resolving power (λ/Δλ= 4000) [lambda/ delta lambda] spectrograph, with a 5mJ [milijoule] energy per 1 ns [nanosecond] pulsed laser radiation, available as a commercially packaged hand-held system. Sand/uranyl fluoride mixtures are prepared to simulate residue likely encountered during decontamination efforts at facilities that handle uranium hexafluoride. Detection limits are described for four uranium lines with one revealing the capability to detect uranium at a level of 250 parts-per-million. Advantages of the studied compact device include that location specific information can be obtained on-site to augment contamination identification.This work also demonstrates the capability of a readily potentially portable Laser Induced Breakdown Spectroscopy (LIBS) system to conduct macroscopic chemical mapping of uranium and iron in surrogate nuclear debris for sample interior and exterior surfaces, for the first time. Techniques focus on the mitigation of chemical and physical matrix effects of four uranium atomic emission lines, relatively free of interferences and of good analytical value. The acceptable data spatial resolution is 0.5 mm [millimeter]. A material fractionation pattern occurs and is discussed in terms of constituent melting temperatures and thermal gradients experienced during the cooling process is proposed.Finally, Areas of further research to advance portable LIBS capabilities for nuclear forensics are discussed

Application and validation of capacitive proximity sensing systems in smart environments

Smart environments feature a number of computing and sensing devices that support occupants in performing their tasks. In the last decades there has been a multitude of advances in miniaturizing sensors and computers, while greatly increasing their performance. As a result new devices are introduced into our daily lives that have a plethora of functions. Gathering information about the occupants is fundamental in adapting the smart environment according to preference and situation. There is a large number of different sensing devices available that can provide information about the user. They include cameras, accelerometers, GPS, acoustic systems, or capacitive sensors. The latter use the properties of an electric field to sense presence and properties of conductive objects within range. They are commonly employed in finger-controlled touch screens that are present in billions of devices. A less common variety is the capacitive proximity sensor. It can detect the presence of the human body over a distance, providing interesting applications in smart environments. Choosing the right sensor technology is an important decision in designing a smart environment application. Apart from looking at previous use cases, this process can be supported by providing more formal methods. In this work I present a benchmarking model that is designed to support this decision process for applications in smart environments. Previous benchmarks for pervasive systems have been adapted towards sensors systems and include metrics that are specific for smart environments. Based on distinct sensor characteristics, different ratings are used as weighting factors in calculating a benchmarking score. The method is verified using popularity matching in two scientific databases. Additionally, there are extensions to cope with central tendency bias and normalization with regards to average feature rating. Four relevant application areas are identified by applying this benchmark to applications in smart environments and capacitive proximity sensors. They are indoor localization, smart appliances, physiological sensing and gesture interaction. Any application area has a set of challenges regarding the required sensor technology, layout of the systems, and processing that can be tackled using various new or improved methods. I will present a collection of existing and novel methods that support processing data generated by capacitive proximity sensors. These are in the areas of sparsely distributed sensors, model-driven fitting methods, heterogeneous sensor systems, image-based processing and physiological signal processing. To evaluate the feasibility of these methods, several prototypes have been created and tested for performance and usability. Six of them are presented in detail. Based on these evaluations and the knowledge generated in the design process, I am able to classify capacitive proximity sensing in smart environments. This classification consists of a comparison to other popular sensing technologies in smart environments, the major benefits of capacitive proximity sensors, and their limitations. In order to support parties interested in developing smart environment applications using capacitive proximity sensors, I present a set of guidelines that support the decision process from technology selection to choice of processing methods

Enhancing interaction in mixed reality

With continuous technological innovation, we observe mixed reality emerging from research labs into the mainstream. The arrival of capable mixed reality devices transforms how we are entertained, consume information, and interact with computing systems, with the most recent being able to present synthesized stimuli to any of the human senses and substantially blur the boundaries between the real and virtual worlds. In order to build expressive and practical mixed reality experiences, designers, developers, and stakeholders need to understand and meet its upcoming challenges. This research contributes a novel taxonomy for categorizing mixed reality experiences and guidelines for designing mixed reality experiences. We present the results of seven studies examining the challenges and opportunities of mixed reality experiences, the impact of modalities and interaction techniques on the user experience, and how to enhance the experiences. We begin with a study determining user attitudes towards mixed reality in domestic and educational environments, followed by six research probes that each investigate an aspect of reality or virtuality. In the first, a levitating steerable projector enables us to investigate how the real world can be enhanced without instrumenting the user. We show that the presentation of in-situ instructions for navigational tasks leads to a significantly higher ability to observe and recall real-world landmarks. With the second probe, we enhance the perception of reality by superimposing information usually not visible to the human eye. In amplifying the human vision, we enable users to perceive thermal radiation visually. Further, we examine the effect of substituting physical components with non-functional tangible proxies or entirely virtual representations. With the third research probe, we explore how to enhance virtuality to enable a user to input text on a physical keyboard while being immersed in the virtual world. Our prototype tracked the user’s hands and keyboard to enable generic text input. Our analysis of text entry performance showed the importance and effect of different hand representations. We then investigate how to touch virtuality by simulating generic haptic feedback for virtual reality and show how tactile feedback through quadcopters can significantly increase the sense of presence. Our final research probe investigates the usability and input space of smartphones within mixed reality environments, pairing the user’s smartphone as an input device with a secondary physical screen. Based on our learnings from these individual research probes, we developed a novel taxonomy for categorizing mixed reality experiences and guidelines for designing mixed reality experiences. The taxonomy is based on the human sensory system and human capabilities of articulation. We showcased its versatility and set our research probes into perspective by organizing them inside the taxonomic space. The design guidelines are divided into user-centered and technology-centered. It is our hope that these will contribute to the bright future of mixed reality systems while emphasizing the new underlining interaction paradigm.Mixed Reality (vermischte Realitäten) gehen aufgrund kontinuierlicher technologischer Innovationen langsam von der reinen Forschung in den Massenmarkt über. Mit der Einführung von leistungsfähigen Mixed-Reality-Geräten verändert sich die Art und Weise, wie wir Unterhaltungsmedien und Informationen konsumieren und wie wir mit Computersystemen interagieren. Verschiedene existierende Geräte sind in der Lage, jeden der menschlichen Sinne mit synthetischen Reizen zu stimulieren. Hierdurch verschwimmt zunehmend die Grenze zwischen der realen und der virtuellen Welt. Um eindrucksstarke und praktische Mixed-Reality-Erfahrungen zu kreieren, müssen Designer und Entwicklerinnen die künftigen Herausforderungen und neuen Möglichkeiten verstehen. In dieser Dissertation präsentieren wir eine neue Taxonomie zur Kategorisierung von Mixed-Reality-Erfahrungen sowie Richtlinien für die Gestaltung von solchen. Wir stellen die Ergebnisse von sieben Studien vor, in denen die Herausforderungen und Chancen von Mixed-Reality-Erfahrungen, die Auswirkungen von Modalitäten und Interaktionstechniken auf die Benutzererfahrung und die Möglichkeiten zur Verbesserung dieser Erfahrungen untersucht werden. Wir beginnen mit einer Studie, in der die Haltung der nutzenden Person gegenüber Mixed Reality in häuslichen und Bildungsumgebungen analysiert wird. In sechs weiteren Fallstudien wird jeweils ein Aspekt der Realität oder Virtualität untersucht. In der ersten Fallstudie wird mithilfe eines schwebenden und steuerbaren Projektors untersucht, wie die Wahrnehmung der realen Welt erweitert werden kann, ohne dabei die Person mit Technologie auszustatten. Wir zeigen, dass die Darstellung von in-situ-Anweisungen für Navigationsaufgaben zu einer deutlich höheren Fähigkeit führt, Sehenswürdigkeiten der realen Welt zu beobachten und wiederzufinden. In der zweiten Fallstudie erweitern wir die Wahrnehmung der Realität durch Überlagerung von Echtzeitinformationen, die für das menschliche Auge normalerweise unsichtbar sind. Durch die Erweiterung des menschlichen Sehvermögens ermöglichen wir den Anwender:innen, Wärmestrahlung visuell wahrzunehmen. Darüber hinaus untersuchen wir, wie sich das Ersetzen von physischen Komponenten durch nicht funktionale, aber greifbare Replikate oder durch die vollständig virtuelle Darstellung auswirkt. In der dritten Fallstudie untersuchen wir, wie virtuelle Realitäten verbessert werden können, damit eine Person, die in der virtuellen Welt verweilt, Text auf einer physischen Tastatur eingeben kann. Unser Versuchsdemonstrator detektiert die Hände und die Tastatur, zeigt diese in der vermischen Realität an und ermöglicht somit die verbesserte Texteingaben. Unsere Analyse der Texteingabequalität zeigte die Wichtigkeit und Wirkung verschiedener Handdarstellungen. Anschließend untersuchen wir, wie man Virtualität berühren kann, indem wir generisches haptisches Feedback für virtuelle Realitäten simulieren. Wir zeigen, wie Quadrokopter taktiles Feedback ermöglichen und dadurch das Präsenzgefühl deutlich steigern können. Unsere letzte Fallstudie untersucht die Benutzerfreundlichkeit und den Eingaberaum von Smartphones in Mixed-Reality-Umgebungen. Hierbei wird das Smartphone der Person als Eingabegerät mit einem sekundären physischen Bildschirm verbunden, um die Ein- und Ausgabemodalitäten zu erweitern. Basierend auf unseren Erkenntnissen aus den einzelnen Fallstudien haben wir eine neuartige Taxonomie zur Kategorisierung von Mixed-Reality-Erfahrungen sowie Richtlinien für die Gestaltung von solchen entwickelt. Die Taxonomie basiert auf dem menschlichen Sinnessystem und den Artikulationsfähigkeiten. Wir stellen die vielseitige Verwendbarkeit vor und setzen unsere Fallstudien in Kontext, indem wir sie innerhalb des taxonomischen Raums einordnen. Die Gestaltungsrichtlinien sind in nutzerzentrierte und technologiezentrierte Richtlinien unterteilt. Es ist unsere Anliegen, dass diese Gestaltungsrichtlinien zu einer erfolgreichen Zukunft von Mixed-Reality-Systemen beitragen und gleichzeitig die neuen Interaktionsparadigmen hervorheben

Machine Learning in Sensors and Imaging

Machine learning is extending its applications in various fields, such as image processing, the Internet of Things, user interface, big data, manufacturing, management, etc. As data are required to build machine learning networks, sensors are one of the most important technologies. In addition, machine learning networks can contribute to the improvement in sensor performance and the creation of new sensor applications. This Special Issue addresses all types of machine learning applications related to sensors and imaging. It covers computer vision-based control, activity recognition, fuzzy label classification, failure classification, motor temperature estimation, the camera calibration of intelligent vehicles, error detection, color prior model, compressive sensing, wildfire risk assessment, shelf auditing, forest-growing stem volume estimation, road management, image denoising, and touchscreens

Nuclear Forensics: Measurements of Uranium Oxides Using Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS)

Over the past decade, law enforcement, governmental and public agencies have been stymied by the threat of the trafficking of nuclear materials. During this time span, reports from the International Atomic Energy Agency of illicit trafficking have increased eightfold from 20 to 160. For this reason, nuclear forensics is a burgeoning science focused on the identification of seized special nuclear materials. Identification of these materials is based upon the wealth of information that can be obtained by applying multiple analytical and measurement technologies. All of the information gained from each sample can then be used to further characterize other samples culminating in the inclusion of all of the collected data into a central database. Information must be reported in a timely manner as actionable results need to be presented as quickly as possible if there is to be any attribution for trafficking of nuclear material. Identification parameters such as uranium content, isotopic composition, and levels of impurities can be measured simultaneously in an effort to completely characterize a sample. All of these measurements combined can offer information as to the source of the material and its intended use. Many of the current analytical techniques used in nuclear forensics require extensive sample preparation and offer minimal amounts of information about the sample. Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS) is presented as a rapid analytical technique that provides many of these identification parameters with minimal sample preparation