The Middlesex University rehabilitation robot

This paper outlines the historical developments of Wheelchair-Mounted Robot Arms (WMRA's) and then focuses on the ongoing research at Middlesex to develop a low-cost aid to daily living for users with high-level quadriplegia. A detailed review is given explaining the design specification. It describes the construction of the robotic device and its control architecture. The prototype robot used several gesture recognition and other input systems. The prototype has been tested on disabled and non-disabled users with positive feedback. They observed that it was easy to use, but issues about speed of operation were resolved after further development. The robot has a payload of greater than 1kg with a maximum reach of 0.7–0.9m. Published by the Taylor & Francis Publishing Group, this publication is one of the only journals to cover the multi-disciplinary area of medical technology research. Currently, research bids are being formulated with the School of Computing Science to continue this research

Intelligent system for interaction with virtual characters based on volumetric sensors

Dissertação de Mestrado, Engenharia Elétrica e Eletrónica, Instituto Superior de Engenharia, Universidade do Algarve, 2015A tecnologia vem sendo desenvolvida para ajudar-nos a completar ou aumentar a produtividade nas nossas tarefas diárias. Muitas das máquinas construídas têm sido progressivamente aperfeiçoadas para funcionar mais como um ser humano, usando para isso os mais variados sensores. Um dos problemas mais desafiantes que a tecnologia encontrou é como dar a uma máquina a capacidade que um "animal" tem de perceber o mundo através do seu sistema visual. Uma solução será usar na máquina sistemas inteligentes que usem visão computacional. Uma grande ajuda pode chegar da perceção de profundidade pela máquina, tornando menos complexa a deteção e a compreensão de objetos numa imagem por parte desta. Com o aparecimento de sensores volumétricos (tridimensional 3D) no mercado consumidor, aumentaram os desenvolvimentos feitos nesta área científica, permitindo assim a sua integração na maioria dos dispositivos, tais como computadores ou dispositivos móveis, a um preço muito competitivo. Os sensores volumétricos podem ser usados nas mais variadas áreas pois apesar de terem aparecido inicialmente na área dos videojogos, estendemse ainda à área de vídeo, modelação 3D, interfaces, jogos ou realidade virtual e aumentada. Esta dissertação foca essencialmente no desenvolvimento de sistemas (inteligentes) baseados em sensores volumétricos (neste caso a Microsoft Kinect) para a interação com avatares ou filmes. Quanto a aplicações na área de vídeo, foi desenvolvida uma solução onde um sensor 3D ajuda um utilizador a seguir uma narrativa que é iniciada assim que o utilizador é detetado, mudando os acontecimentos do vídeo consoante ações pré-determinadas do utilizador. O utilizador pode então mudar o rumo da história mudando de posição ou efetuando um gesto. Esta solução é ilustrada utilizando retroprojeção, existindo ainda a possibilidade de ser apresentada em modo holograma numa abordagem à escala. O descrito no anterior parágrafo pode também ser aplicada a uma solução de vertente mais comercial. Para isso, foi desenvolvido uma aplicação altamente configurável, podendo-se ajustar (em termos visuais) às necessidades de diferentes companhias. O ambiente gráfico é acompanhado por um avatar ou por um video (previamente gravado), que interage com um utilizador através de gestos, dando uma sensação mais realista devido à utilização de holografia. Ao interagir com a instalação, são registados todos os movimentos e interações efetuadas pelo utilizador para que estatísticas sejam construídas, de maneira a perceber os conteúdos com mais interesse bem como as áreas físicas com mais interação. Adicionalmente, o utilizador poderá ter a sua fotografia completa ou tipo BI extraída, podendo-lhe ser oferecidos em produtos promocionais da empresa. Devido à curta área de interação oferecida por um sensor deste tipo (Kinect), foi também desenvolvida a possibilidade de juntar vários sensores, 4 para cobrir 180º (graus) em frente da instalação ou ainda 8 para cobrir os 360º à volta da instalação, de maneira a que os utilizadores possam ser detetados por qualquer um deles e que não sejam perdidos quando atravessam para uma zona de outro sensor, ou mesmo quando saem do campo de visão dos sensores e retornam mais tarde. Apesar dos sensores referidos serem mais conhecidos na interação com um jogo virtual, jogos reais e físicos também podem beneficiar deste tipo de sensor. Neste último ponto, é apresentada uma ferramenta de realidade aumentada para snooker ou bilhar. Nesta aplicação, um sensor 3D colocado por cima da mesa, capta a área de jogo sendo depois processada para que sejam detetadas as bolas, o taco e as tabelas. Sempre que possível, esta deteção é feita usando a terceira dimensão (profundidade) oferecida por estes sensores, tornando-se por exemplo mais robusto a mudanças quanto a condições luminosas. Com estes dados é então previsto, utilizando álgebra vetorial, a trajetória da bola, sendo projetado o resultado na mesa

Perceptual training effects on anticipation of direct and deceptive 7-meter throws in team handball

University of Minnesota Ph.D. dissertation. May 2014. Major: Kinesiology. Advisor: Michael G. Wade. 1 computer file (PDF); vi, 123 pages.This research investigated the effects of video-based perceptual training on the performance of handball goalkeepers when anticipating the directions of both direct and deceptive 7-meter throws (i.e., penalty throws). Forty two Kuwaiti handball goalkeepers voluntarily participated in this study and were randomly assigned to 3 matched-ability groups based on their pre-test performance: participants in the perceptual training group received video-based perceptual training over 7 consecutive days; participants in the placebo training group received video-based regular training; and participants in the control group received no training. The primary findings demonstrated that video-based perceptual training significantly improved anticipatory performances from pre- to post-test under both throwing conditions (i.e., direct and deceptive). Although perceptual training significantly improved anticipation of direct and deceptive throws, anticipation of deceptive throws showed less improvement. The current findings support the first research hypothesis that perceptual training group would improve their anticipation under both throwing conditions more than placebo training and control groups. The findings also support the second research hypothesis that anticipation of deceptive 7-m throws would show less improvement compared to anticipation of direct throws. In conclusion, this study confirms the importance of perceptual training for anticipation skills in sport and adds to the literature that perceptual training can also improve anticipation of deceptive actions. In addition, this study confirms that deception in handball is a challenging task that goalkeepers can minimize, but cannot eliminate, its effect by enhancing their perceptual skills

The design and evaluation of an interface and control system for a scariculated rehabilitation robot arm

This thesis is concerned with the design and development of a prototype implementation of a Rehabilitation Robotic manipulator based on a novel kinematic configuration. The initial aim of the research was to identify appropriate design criteria for the design of a user interface and control system, and for the subsequent evaluation of the manipulator prototype. This led to a review of the field of rehabilitation robotics, focusing on user evaluations of existing systems. The review showed that the design objectives of individual projects were often contradictory, and that a requirement existed for a more general and complete set of design criteria. These were identified through an analysis of the strengths and weaknesses of existing systems, including an assessment of manipulator performances, commercial success and user feedback. The resulting criteria were used for the design and development of a novel interface and control system for the Middlesex Manipulator - the novel scariculated robotic system. A highly modular architecture was adopted, allowing the manipulator to provide a level of adaptability not approached by existing rehabilitation robotic systems. This allowed the interface to be configured to match the controlling ability and input device selections of individual users. A range of input devices was employed, offering variation in communication mode and bandwidth. These included a commercial voice recognition system, and a novel gesture recognition device. The later was designed using electrolytic tilt sensors, the outputs of which were encoded by artificial neural networks. These allowed for control of the manipulator through head or hand gestures. An individual with spinal-cord injury undertook a single-subject user evaluation of the Middlesex Manipulator over a period of four months. The evaluation provided evidence for the value of adaptability presented by the user interface. It was also shown that the prototype did not currently confonn to all the design criteria, but allowed for the identification of areas for design improvements. This work led to a second research objective, concerned with the problem of configuring an adaptable user interface for a specific individual. A novel form of task analysis is presented within the thesis, that allows the relative usability of interface configurations to be predicted based upon individual user and input device characteristics. An experiment was undertaken with 6 subjects performing 72 tasks runs with 2 interface configurations controlled by user gestures. Task completion times fell within the range predicted, where the range was generated using confidence intervals (α = 0.05) on point estimates of user and device characteristics. This allowed successful prediction over all task runs of the relative task completion times of interface configurations for a given user

Interaction between different sources of situational probability information to anticipate the bowler’s intention in cricket

In elite fastball sports, such as cricket, performance occurs at the limit of human capability as the time constraints of perceiving and acting are severe. Cricket batsmen are therefore required to use the two sources of advanced information (kinematic cues and situational probability) to anticipate an upcoming delivery to negate the effects of the time constraints. The source of information that will be focused on in this study will be situational probability, with the aim being to determine the interaction between bowling sequence and field placement as sources of situational probability used by skilled cricket batsmen to predict a bowler’s intention. Four different conditions were created according to the situational probability information presented to the batsmen, namely no sources, sequence alone, field placement alone, and both sources. Fifteen skilled cricket batsmen were required to face deliveries projected by a bowling machine and make predictions as to where the next delivery outcome was going to pitch based on perceived situational probability information and attempt to make successful bat-ball contact. In order to compare the use and importance of the four conditions of situational probability information,prediction accuracy, response accuracy and the initial movement time of the batsmen were recorded and analysed. Results of the study revealed no significant difference between conditions of situational probability presented to batsmen for prediction accuracy, response accuracy, and initial movement time. However, significant differences were found between categories of congruence for prediction accuracy results. The prediction accuracy results reveal that batsmen equally value each source of situational probability information and that when sources were presented in conjunction with each other, no enhancement in anticipatory performance or interception of the cricket ball occurred.The results of the current study suggest that it is not necessarily the number of sources present, but rather the relevance of the source that is most important for a batsman to predict the outcome of a delivery. The prediction accuracy of batsmen is dependent on the nature of the information presented rather than the amount of information presented. Performers draw upon more pertinent information variables according to the relevance to the task at hand.The response accuracy results reveal that the batsmen have the required action capabilities to make successful bat-ball contact regardless of whether or not they correctly anticipate the upcoming delivery’s landing position

Training and testing of 1v1 agility in Australian football

Little is known of how agility events occur in the sport of Australian football (AF). As a result, appropriate training and testing methods are unknown. This thesis investigated 1v1 agility in AF to evaluate alternative methods for training and testing agility. The thesis was undertaken in three studies. Study one investigated if training and testing practices used in elite AF align with the demands of competition. A notational analysis revealed substantial variation in movement patterns used by, and the cognitive demands of, athletes in agility events. A survey of high-performance managers in the AFL revealed that a mixture of open and closed training methods are used in elite AF, and that subjective agility assessment is preferred to formal testing. Study two assessed the reliability and ecological validity of a field-based test of attacking and defending agility for AF. The text exhibited excellent inter-rater and intra-rater reliability, as well as moderate test-retest reliability. Characteristics of the test were compared to the notational analysis to assess the ecological validity of the test. While the test did not fully replicate the agility demands of AF, the test improved ecological validity when compared to previous tests described in the literature. Study three evaluated the effectiveness of a four-week 1v1 training intervention for improving attacking and defending agility in Australian footballers. In addition, the study assessed the crossover of attacking training to defending agility and defending training to attacking agility. Improvements in attacking agility were found which were greater for attacking-trained athletes. However, no improvements in defending agility were realised. This thesis indicates that 1v1 training and testing is suitable for assessing and developing agility in Australian footballers. However, 1v1 training may be more suitable for improving attacking agility. Further, agility is context-specific, and testing and training should consider the role of the athlete.Doctor of Philosoph

Video-based step measurement in sport and daily living.

Current knowledge of tennis player-surface interactions with different court surfaces is limited. The measurement of player step and movement strategy would aid the understanding of tennis player-surface interaction. However, this has not yet been performed: no readily available motion analysis tool is capable of measuring spatio-temporal parameters of gait during match-play tennis. The purpose of this project was to develop, validate and use a motion analysis tool designed to measure player location and foot-surface contacts during match-play tennis.Single camera video footage, obtained from the 2011 Roland Garros Qualifying Tournament, was manually digitised to characterise step and movement strategy during men's and women's forehand groundstrokes. Player movements were consistent with previous notational analyses; however gender differences were highlighted for step frequency. Initial findings were limited by manual analysis, e.g. manual digitising subjectivity and low sample size: an objective and automated system was required.A markerless, view-independent, foot-surface contact identification (FSCi) algorithm was developed. The FSCi algorithm identifies foot-surface contacts in image sequences of gait by quantifying the motion of each foot. The algorithm was validated using standard colour image sequences of walking and running obtained from four unique camera perspectives: output data were compared to three-dimensional motion analysis. The FSCi algorithm identified data for 1243 of 1248 foot-surface contacts; root-mean-square error (RMSE) was 52.2 and 103.4 mm for shod walking and running respectively (all camera perspectives). Findings demonstrated that the FSCi algorithm measured basic, spatio-temporal parameters of walking and running, e.g. step length and step time, without interfering with the activity being observed. Furthermore, analyses were independent of camera view.Video footage obtained from the 2011 ATP World Tour Finals was used to develop a combined player tracking and foot-surface contact identification (PT-FSCi) algorithm. Furthermore, a graphical user interface was developed. The PT-FSCi algorithm was used to analyse twenty match-play tennis rallies: output data were compared to manual digitising. The PT-FSCi algorithm tracked player position and identified data for 832 of 890 foot-surface contacts during match-play tennis. RMSE for player position and foot-surface contacts was 232.9 and 121.9 mm respectively. The calculation of step parameters required manual intervention: this reflected the multi-directional nature of tennis. This represents a limitation to the current algorithm however the segmentation of player movement phases to allow the automatic calculation of step parameters.The analysis of this data indicated that top ranked tennis players can win rallies using movement strategies previously considered to be defensive. Furthermore, step length data indicated that shorter step lengths formed the majority of step strategy. The largest 25% of steps were observed behind the baseline, aligned with deuce and advantage court sidelines. This reflected lunging and turning manoeuvres at lateral extremes of player movement.The single camera system that has resulted from this project will enable the International Tennis Federation to characterise player step and movement strategy during match-play tennis. This will allow a more informed approach to player-surface interaction research. Furthermore, the system has potential to be used for different applications, ranging from sport to surveillance

Real-time analysis and feedback of performance indicators in elite diving

The difficulty and quality of dives required to win medals in Olympic springboard diving has increased throughout the modern era. A greater understanding of optimal diving technique, increased training opportunity and support from disciplines of sports science and medicine have influenced this trend. Progress towards world class standards is enhanced by objective measurement of performance in a training and competition context from which an assessment of the effect of training interventions can be made, leading to a programme individualised for each diver. A description of kinematic parameters representing high quality performance of the world’s hardest dives did not exist. Standards were therefore defined following analysis of dives performed over five years of springboard competition. This new knowledge contributes to a model called ‘What It Takes To Win’ (WITTW). A practical method to calculate kinematic metrics from dives in training also did not exist, limiting comparison between training and WITTW standards. To bridge this gap, a flexible method for analysing dives in training and competition was developed and a bespoke tool created to calculate and feedback performance data with a greater level of sensitivity than in related studies in the sport. Automatic tracking was designed and implemented to facilitate ‘real-time’ measurement of kinematic data, providing a new training process where objective data added to subjective interpretation of quality throughout training. Four World Class Programme divers were tracked through a season’s preparatory phase. Change in performance was measured and an analysis conducted to compare progress towards WITTW standards and assess the influence of strength and conditioning training in performance outcomes. Statistical analysis of longitudinal training data showed that independent variables relating to ‘best’ performances were not common to all divers and that an individualised set of critical variables could be identified for each diver as strengths around which to focus training