Visual demand evaluation methods for in-vehicle interfaces

Advancements in computing technology have been keenly felt in the automotive industry. Novel in-car systems have the potential to substantially improve the safety, efficiency and comfort of the driving experience. However, they must be carefully designed, so their use does not dangerously distract drivers from fundamental, safety-critical driving tasks. Distraction is a well-established causal factor in road accidents. A concern is that the introduction of new in-vehicle technology may increase exposure to distraction, and lead to an increase in distraction-related accidents. The range of systems often termed In-Vehicle Information Systems (IVIS), encompassing navigation and entertainment systems, in-car email and Internet, are the focus of this thesis, since they are commonly associated with long tasks that are not considered fundamentally relevant to driving. A variety of Human-Computer Interaction (HCI) and Human Factors methods has been employed to assess the potential distraction of IVIS task engagement. These include on-road evaluations, driving simulator studies, and surrogate methods, such as peripheral detection tasks and static task time assessments. The occlusion technique is one such surrogate, where task performance is assessed under intermittent vision conditions. Participants complete a task with 1.5-second vision periods, followed by a period where their vision is occluded. In this way, the technique evaluates how visually demanding a task is, mimicking the behaviour of glancing to and from the forward road scene when driving and performing IVIS tasks. An evaluation of the technique's validity is presented. Sixteen participants performed two tasks on two systems under three conditions: static (full-vision), static (occlusion), and, whilst driving. Results confirmed other research, concluding that the technique is valid. However, the method's assessment through user-trials based on measures of human performance is problematic. Such trials require robust, reliable prototype systems, and can therefore only take place in later design stages. Consequently, the economic effectiveness of the technique is questionable. The keystroke-level model (KLM), which predicts task times for error-free performance by expert users in routine tasks, provides an alternative quantitative assessment method to user-trials. Tasks are decomposed into their most primitive actions, termed operators, which are associated with empirically assessed time values. These values are then summed to predict performance times. An evaluation of the technique in a vehicle environment is presented; twelve participants performed eleven tasks on two in-car entertainment systems, and task times were compared with KLM predictions. Results demonstrate the technique remains valid beyond its original, desktop computing based context. However, the traditional KLM predicts static task time only, and an extended procedure is required to consider occluded task performance. Two studies are presented, seeking to extend the KLM in order to model task performance under the interrupted vision conditions of occlusion trials. In the first, predictions of occlusion metrics are compared with results from the earlier occlusion assessment. In the second, twelve participants performed three tasks on two IVIS systems under occlusion conditions. Results were subsequently compared with predicted values. Both studies conclude that the extended KLM approach produces valid predictions of occlusion methods, with error rates generally within 20% of observed values, in line with expectations for KLM predictions. Subsequently, a case study is presented, to demonstrate the technique's reliability. The results of an independent occlusion study of two IVIS tasks are compared with predictions made by a HCI expert trained in the application of the extended KLM. Error rates for this study were equally low, leading to the conclusion that the extended KLM appears reliable, though further studies are required. It is concluded that the extended-KLM technique is a valid, reliable and economical method for assessing the visual demand of IVIS tasks. In contrast to many user-trial methods, the technique can be applied in early design stages. In addition, future work areas are identified, which could serve to further enhance the validity, reliability and economy of the technique. These include, automating the extended KLM procedure with a software tool, and, the development of new cognitive and physical operators, and new assumptions, specific to IVIS and/or occlusion conditions. For example, it will be useful to develop new cognitive operators that consider the time taken to visually reorient to complex displays following occluded periods

ESTUDO DE FERRAMENTA ALTERNATIVA DE CAPTURA DE MOVIMENTOS DE CABEÇA PARA APLICAÇÕES DE REALIDADE VIRTUAL.

Virtual reality, interactivity , computer graphicsThis work uses an alternative methodology to capture head movements of a user for navigation in virtual scenarios applied in trials for virtual reality. Results in the improvement of an alternative system, for this motion capture , cheaper , and easier to use by ordinary users Realidade Virtual, interatividade, computação gráficaEste trabalho utiliza uma técnica alternativa na captura de movimentos da cabeça, para navegação em cenários virtuais, voltado para experimentações para realidade virtual. Tem como resultado o aprimoramento de um sistema alternativo, para essa captura de movimentos, mais barato, e de mais fácil utilização por parte de usuários comuns

Virtual Techniques for Prototype HMI Evaluation

The aim of this project was to investigate the behavioural validity of virtual methods, namely driving simulators and computational models, as prototype HMI evaluation tools. A driving study was designed where participants had to perform secondary tasks while driving in a real world and a driving simulator setting. Statistical analysis of the data, along with an in-depth review of related findings was used to identify the levels of behavioural validity that could be achieved by different simulator settings across different metrics. A further analysis was performed to identify behavioural strategies that drivers employ regarding their visual attention sharing while executing HMI tasks concurrently to driving. Finally, two existing computational models were validated and a novel model was proposed that can account for drivers’ behavioural phenomena, not previously accounted for

Design no desenvolvimento de um projeto de interface : aprimorando o processo de modelagem em programas de estruturas tridimensionais por barras

O presente trabalho tem por objetivo criar um protótipo de interface para um software de análise de estruturas tridimensionais por barras, promovendo a usabilidade e reduzindo a carga cognitiva dos usuários no processo de modelagem por meio das heurísticas de usabilidade e da modelagem preditiva do comportamento humano. Para tal, o levantamento bibliográfico compreende temas como Ergonomia, Usabilidade, Modelagem Preditiva do Comportamento Humano, Heurísticas de Usabilidade, Interface Gráfica do Usuário e levantamento de softwares de análise estrutural por barras, através dos quais se busca entender os procedimentos de modelagem estrutural. Para atingir o objetivo geral foram traçados objetivos específicos, os quais consistem na identificação e análise dos procedimentos de modelagem, na verificação de dificuldades de interação e proposição de alternativas para melhoria. A verificação das dificuldades foi realizada através da ferramenta KLM-GOMS (Keystroke-Level Model - Goals, Operators, Methods, Selection Rules), a qual apresenta uma metodologia para mensurar a carga cognitiva, através do tempo de interação necessário, de interação com uma interface para realização de atividades específicas) e das heurísticas da usabilidade. Para tal, foram estabelecidas atividades que deviam ser cumpridas pelos softwares selecionados, resultando em um grande volume de dados. A partir destes dados, forem desenvolvidas alternativas as quais foram concebidas iterativamente, e resultaram em 3 opções: a primeira sugere a mescla dos procedimentos adotados pelos softwares estudados, selecionando-se os que apresentaram os melhores resultados em termos de redução da carga cognitiva. A segunda alternativa abrange esses mesmos procedimentos, porém com melhorias realizadas de acordo com os problemas encontrados através dos tempos mensurados. E a terceira alternativa consiste em considerações de usabilidade, as quais resultam na concepção da reutilização de conceitos e na geração de alternativas diferentes para melhorar o desempenho da modelagem. Esta terceira alternativa da origem ao protótipo que é objetivo da pesquisa. Seu desenvolvimento foi realizado através do Adobe XD, uma ferramenta de prototipagem de interfaces. Durante a criação do protótipo todos os passos obtidos através do KLM-GOMS foram revisados e ajustados, passando de uma ferramenta teórica para prática. O protótipo resultante diminuiu o tempo previsto de modelagem de uma estrutura em cerca de 33% em relação ao melhor resultado obtido pelos softwares estudados. As principais alterações referem-se à interação de modelagem geométrica, aplicação das restrições, e aplicação das cargas. Nessas duas últimas, o resultado foi um novo paradigma de modelagem, o qual apresenta, como principal característica, uma configuração visual e geométrica em detrimento dos formulários normalmente utilizados. Também foi realizada a implementação de catálogos de materiais e seções, os quais apresentam impacto significativo na redução da carga cognitiva.The present work aims to create a prototype of an interface for software analysis of three-dimensional structures by bars, promoting usability and reducing the cognitive load of users in the modeling process through usability heuristics and predictive modeling of human behavior. To this end, the bibliographic survey comprises topics such as Ergonomics, Usability, Predictive Modeling of Human Behavior, Usability Heuristics, Graphical User Interface and survey of structural analysis software by bars, through which one seeks to understand the structural modeling procedures. To achieve the general objective, specific objectives were drawn up, which consist of the identification and analysis of the modeling procedures, the verification of interaction difficulties and the proposition of alternatives for improvement. The verification of difficulties was performed using the KLM-GOMS tool (Keystroke-Level Model - Goals, Operators, Methods, Selection Rules), which presents a methodology to measure the cognitive load, through the necessary interaction time, interaction with a interface for carrying out specific activities) and usability heuristics. To this end, activities were established that should be performed by the selected software, resulting in a large volume of data. From these data, alternatives are developed which were designed iteratively, and resulted in 3 options: the first suggests the mixture of the procedures adopted by the studied software, selecting the ones that presented the best results in terms of reducing the cognitive load. The second alternative covers these same procedures, but with improvements made according to the problems found through the measured times. And the third alternative consists of usability considerations, which result in the conception of the reuse of concepts and in the generation of different alternatives to improve the performance of the modeling. This third alternative from the origin to the prototype that is the objective of the research. Its development was carried out through Adobe XD, an interface prototyping tool. During the creation of the prototype, all steps obtained through KLM-GOMS were reviewed and adjusted, moving from a theoretical to a practical tool. The resulting prototype reduced the estimated time for modeling a structure by about 33% in relation to the best result obtained by the studied software. The main changes refer to the interaction of geometric modeling, application of restrictions, and application of loads. In these last two, the result was a new modeling paradigm, which presents, as its main characteristic, a visual and geometric configuration to the detriment of the forms normally used. Catalogs of materials and sections were also implemented, which have a significant impact on reducing cognitive load

Visual demand evaluation methods for in-vehicle interfaces

Advancements in computing technology have been keenly felt in the automotive industry. Novel in-car systems have the potential to substantially improve the safety, efficiency and comfort of the driving experience. However, they must be carefully designed, so their use does not dangerously distract drivers from fundamental, safety-critical driving tasks. Distraction is a well-established causal factor in road accidents. A concern is that the introduction of new in-vehicle technology may increase exposure to distraction, and lead to an increase in distraction-related accidents. The range of systems often termed In-Vehicle Information Systems (IVIS), encompassing navigation and entertainment systems, in-car email and Internet, are the focus of this thesis, since they are commonly associated with long tasks that are not considered fundamentally relevant to driving. A variety of Human-Computer Interaction (HCI) and Human Factors methods has been employed to assess the potential distraction of IVIS task engagement. These include on-road evaluations, driving simulator studies, and surrogate methods, such as peripheral detection tasks and static task time assessments. The occlusion technique is one such surrogate, where task performance is assessed under intermittent vision conditions. Participants complete a task with 1.5-second vision periods, followed by a period where their vision is occluded. In this way, the technique evaluates how visually demanding a task is, mimicking the behaviour of glancing to and from the forward road scene when driving and performing IVIS tasks. An evaluation of the technique's validity is presented. Sixteen participants performed two tasks on two systems under three conditions: static (full-vision), static (occlusion), and, whilst driving. Results confirmed other research, concluding that the technique is valid. However, the method's assessment through user-trials based on measures of human performance is problematic. Such trials require robust, reliable prototype systems, and can therefore only take place in later design stages. Consequently, the economic effectiveness of the technique is questionable. The keystroke-level model (KLM), which predicts task times for error-free performance by expert users in routine tasks, provides an alternative quantitative assessment method to user-trials. Tasks are decomposed into their most primitive actions, termed operators, which are associated with empirically assessed time values. These values are then summed to predict performance times. An evaluation of the technique in a vehicle environment is presented; twelve participants performed eleven tasks on two in-car entertainment systems, and task times were compared with KLM predictions. Results demonstrate the technique remains valid beyond its original, desktop computing based context. However, the traditional KLM predicts static task time only, and an extended procedure is required to consider occluded task performance. Two studies are presented, seeking to extend the KLM in order to model task performance under the interrupted vision conditions of occlusion trials. In the first, predictions of occlusion metrics are compared with results from the earlier occlusion assessment. In the second, twelve participants performed three tasks on two IVIS systems under occlusion conditions. Results were subsequently compared with predicted values. Both studies conclude that the extended KLM approach produces valid predictions of occlusion methods, with error rates generally within 20% of observed values, in line with expectations for KLM predictions. Subsequently, a case study is presented, to demonstrate the technique's reliability. The results of an independent occlusion study of two IVIS tasks are compared with predictions made by a HCI expert trained in the application of the extended KLM. Error rates for this study were equally low, leading to the conclusion that the extended KLM appears reliable, though further studies are required. It is concluded that the extended-KLM technique is a valid, reliable and economical method for assessing the visual demand of IVIS tasks. In contrast to many user-trial methods, the technique can be applied in early design stages. In addition, future work areas are identified, which could serve to further enhance the validity, reliability and economy of the technique. These include, automating the extended KLM procedure with a software tool, and, the development of new cognitive and physical operators, and new assumptions, specific to IVIS and/or occlusion conditions. For example, it will be useful to develop new cognitive operators that consider the time taken to visually reorient to complex displays following occluded periods.EThOS - Electronic Theses Online ServiceGBUnited Kingdo