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A construção de modelos representa uma perspectiva interessante para buscar a compreensão sobre aspectos do comportamento humano. A partir de modelos do desempenho humano e do estudo das características do erro humano, este trabalho propõe o S. PERERE (Simulation of Performance in Error), um simulador computacional do comportamento humano cujo objetivo é produzir de forma aleatória estados de erro humano. O simulador recebe como entrada a especificação do comportamento a ser simulado e produz como saída o comportamento afetado pelo erro. Para a geração dos estados de erro o S. PERERE possui um mecanismo perturbador do comportamento e também um mecanismo de disparo das perturbações. A construção do simulador está baseada na arquitetura cognitiva ACT-R (Atomic Components of Thought – Rational). A utilização prevista do S. PERERE é seu acoplamento com simuladores de processos de forma a permitir a verificação do impacto dos erros humanos nestes processos. / The construction of models represents an interesting perspective to reach the understanding about human behaviour aspects. From human performance models and from the study of error characteristics, this work purposes the S.PERERE (Simulation of Performance in Error), a human behaviour computational simulator, which main objective is to produce, in a random way, human error states. The simulator receives, as entrance, the specification of the behaviour to be simulated, and produces, as output, the behaviour affected by the error. For the generation of error states, S.PERERE has a behaviour disturber mechanism and also a mechanism to start the perturbations. The construction of the simulator is based on ACT-R (Atomic Components of Thought – Rational) cognitive architecture. The use of S.PERERE is under its coupling to process simulators, allowing the verification of human errors impact on theses processes.

A construção de modelos representa uma perspectiva interessante para buscar a compreensão sobre aspectos do comportamento humano. A partir de modelos do desempenho humano e do estudo das características do erro humano, este trabalho propõe o S. PERERE (Simulation of Performance in Error), um simulador computacional do comportamento humano cujo objetivo é produzir de forma aleatória estados de erro humano. O simulador recebe como entrada a especificação do comportamento a ser simulado e produz como saída o comportamento afetado pelo erro. Para a geração dos estados de erro o S. PERERE possui um mecanismo perturbador do comportamento e também um mecanismo de disparo das perturbações. A construção do simulador está baseada na arquitetura cognitiva ACT-R (Atomic Components of Thought – Rational). A utilização prevista do S. PERERE é seu acoplamento com simuladores de processos de forma a permitir a verificação do impacto dos erros humanos nestes processos. / The construction of models represents an interesting perspective to reach the understanding about human behaviour aspects. From human performance models and from the study of error characteristics, this work purposes the S.PERERE (Simulation of Performance in Error), a human behaviour computational simulator, which main objective is to produce, in a random way, human error states. The simulator receives, as entrance, the specification of the behaviour to be simulated, and produces, as output, the behaviour affected by the error. For the generation of error states, S.PERERE has a behaviour disturber mechanism and also a mechanism to start the perturbations. The construction of the simulator is based on ACT-R (Atomic Components of Thought – Rational) cognitive architecture. The use of S.PERERE is under its coupling to process simulators, allowing the verification of human errors impact on theses processes.

The problem addressed in this research is the need for supervisory or system summary displays for the Advanced Tomahawk Weapons Control System (ATWCS). These displays are needed to accurately depict the current system state and weapon status in order to aid strike supervisory personnel in making correct and timely decisions. This research examined the problem in the context of designing a set of graphical displays that extracts information relevant to the strike supervisor from ATWCS and displays it in a manner that allows both rapid and accurate interpretation. The approach used to solve the problem progressed in four distinct phases. The first phase, Requirements Analysis, consisted of gathering system requirements through interviews with U.S. Navy officers who have experience as strike warfare supervisors. In the second phase, an initial design was produced using Century Computing's rapid prototyping tool TAE Plus Workbench(TM). The third phase involved the heuristic and guideline evaluation of the prototype based on accepted user interface design principles and ATWCS user interface requirement specifications. This evaluation produced a second iteration prototype that was used in the final phase, Usability Testing. The prototype was tested by U.S. Navy Officers with Tomahawk strike experience and test results were recorded. Changes were then made to the prototype to correct usability problems discovered by the user testing, yielding a third iteration prototype. The final result of this research is a set of prototype displays, in both paper and TAE Plus Workbench(TM) resource file formats, that will be provided to Naval Command, Control, and Ocean Surveillance Center (NCCOSC) Research, Development, Test and Evaluation Division (NRaD) for consideration during system design and implementation.

This thesis describes the development and evaluation of a theoretical framework to account for the dynamic aspects of behaviour at the Human-Computer Interface (HCIF). The purpose behind this work is to allow for the consideration of dynamic Human-Computer Interaction (HCI) in the design of interactive computer systems, and to facilitate the generation of design tools for this purpose. The work describes an example of a design tool which demonstrates how designers of interactive computer systems may account for some aspects of the dynamics of behaviour, involved with the use of computers, in the design of new interactive systems. The thesis offers empirical and literary evidence to support the validity of the dynamic factors governing the interaction of humans with computers.

Identifying finger and wrist flexion based actions using single channel surface electromyogram have a number of rehabilitation, defence and human computer interface applications. These applications are currently infeasible because of unreliability in classification of sEMG when the level of muscle contraction is low and when there are multiple active muscles. The presence of noise and cross-talk from closely located and simultaneously active muscles is exaggerated when muscles are weakly active such as during maintained wrist and finger flexion. It has been established in literature that surface electromyogram (sEMG) and other such biosignals are fractal signals. Some researchers have determined that fractal dimension (FD) is related to strength of muscle contraction. On careful analysis of fractal properties of sEMG, this research work has established that FD is related to the muscle size and complexity and not to the strength of muscle contraction. The work has also identified a novel feature, maximum fractal length (MFL) of the signal, as a good measure of strength of contraction of the muscle. From the analysis, it is observed that while at high level of contraction, root mean square (RMS) is an indicator of strength of contraction of the muscle, this relationship is not very strong when the muscle contraction is less than 50% maximum voluntary contraction. This work has established that MFL is a more reliable measure of strength of contraction compared to RMS, especially at low levels of contraction. This research work reports the use of fractal properties of sEMG to identify the small changes in strength of muscle contraction and the location of the active muscles. It is observed that fractal dimension (FD) of the signal is related with the properties of the muscle while maximum fractal length (MFL) is related to the strength of contraction of the associated muscle. The results show that classifying MFL and FD of a single channel sEMG from the forearm it is possible to accurately identify a set of finger and wrist flexion based actions even when the muscle activity is very weak. It is proposed that such a system could be used to control a prosthetic hand or for human computer interface.

The recent advent of consumer grade Brain-Computer Interfaces (BCI) provides a new revolutionary and accessible way to control computers. BCI translate cognitive electroencephalography (EEG) signals into computer or robotic commands using specially built headsets. Capable of enhancing traditional interfaces that require interaction with a keyboard, mouse or touchscreen, BCI systems present tremendous opportunities to benefit various fields. Movement restricted users can especially benefit from these interfaces. In this thesis, we present a new way to interface a consumer-grade BCI solution to a mobile robot. A Red-Green-Blue-Depth (RGBD) camera is used to enhance the navigation of the robot with cognitive thoughts as commands. We introduce an interface presenting 3 different methods of robot-control: 1) a fully manual mode, where a cognitive signal is interpreted as a command, 2) a control-flow manual mode, reducing the likelihood of false-positive commands and 3) an automatic mode assisted by a remote RGBD camera. We study the application of this work by navigating the mobile robot on a planar surface using the different control methods while measuring the accuracy and usability of the system. Finally, we assess the newly designed interface’s role in the design of future generation of BCI solutions.