Two studies were devised to determine why the difference in manual aiming performance, between full vision and no vision, is decreased for a randomized visual feedback schedule. In study one, aiming accuracy and precision was assessed for up to four trials in the same vision condition, following a switch in visual feedback availability. In experiment one, visual feedback availability was uncertain; while in experiment two, certainty was provided. Results of both experiments revealed that the precision of the first trial immediately following the switch in visual condition was reminiscent of the trial that preceded it, even when performed under different visual conditions. For study two, the inter-trial interval was evaluated by extending the interval to five seconds. Results indicated no reminiscence effect. Overall, we suggest that when the inter-trial trial is brief, individuals rely on offline visual information from the preceding trial to plan the subsequent movement, regardless of certainty.

The aim of this study is to develop a set-up that can be used by patients performing posterior pelvic tilt exercises to assess and improve the effectiveness of the exercise by visual feedbacks. Lifetime of low back pain prevalence is between %60 and %90. In other words almost everyone encounters the problem of low back pain sometime during their life. Therapeutic and protective exercises are the most important components of treatment for the low back pain. People who have mechanical based low back pain due to postural disorders, have weakness of abdominal and back muscles. Posterior pelvic tilt exercises are one of the effective types of exercises to solve this problem. These can be done standing against a wall or lying on a surface. These exercises are advised to patients generally as home exercise programs. However most patients cannot do their exercises effectively due to lack of training and control. In posterior pelvic tilt exercise, the patient is asked to straighten his/her lumbar lordosis and exert as much pressure as possible to the surface he/she is lying on. It is believed that the efficiency of the exercise is correlated with the amount of this pressure. Entertaining visual feedback may increase patient&amp / #8217 / s motivation and consequently quality of the exercise. In this experimental set-up, pressure variations were determined by three receivers which were placed under the back of the patient to provide feedback for proper posterior pelvic tilt exercises. By means of this experimental set-up training for these exercises was achieved easily and the quality of exercises was improved.

The visual feedback loop has long-been ignored as a form and an aesthetic within new media. Media theories have largely assumed a medium is defined by the material technology, relegating visual feedback to a circumstance of media rather than a unique and well-defined concept. This thesis sets forth a criteria for characterizing the visual feedback loop as a desired form, that is, a distinct set of formal and phenomenological qualities that are independent of a medium. Grounding the criteria are the cinema theories of Gilles Deleuze and Sean Cubitt; these theories propose that the cinematic image relates visual forms to generate information in decoding rather represents information directly. The thesis elaborates the theoretical concepts in examples of visual feedback loops from video (Nam June Paikâ s TV Buddha, Bruce Naumanâ s Live Taped Video Corridor), new media art (Daniel Rozinâ s physical mirrors), and digital technologies (GPS navigation systems). To reconcile the visual feedback loop within media theories, the thesis calls for a radical change in how theorists define a medium. Moving away from notions of inscription and materiality, media now rely on a collapsed distinction between sender and receiver. Hence, visual feedback loops exist as remediations of a conceptual framework rather than a technological one, and so require a logic within media theory that allow for the rise of other desired forms like the visual feedback loop.

Abstract This project illustrates the use of the human's ability to balance according to his center of gravity as demonstrated in two applications. The center of gravity of a human is explained in detail in order to use it in controlling the Aldebaran NAO robot and in the robot-assisted balance training. The first application explains how a humanoid robot can mimic a human's movements via a three dimensional depth sensor where the sensor analyzes the position of a user's limbs and how the robot can lift one foot and balance on the other by redistributing the its body mass when the user lifts his foot. The results showed that this algorithm enabled NAO to successfully mimic the users' arms, and was able to balance on one foot by repositioning its center of mass. The second application investigates how individuals with stroke lean when undergoing robot-assisted balance training. In some instances, they can develop inappropriate leaning behaviors during the training. The Kinect sensor is used to assist in optimizing patients' results by integrating it with the training program. The results showed that the Kinect sensor can improve the efficiency of the process by giving users graphical information about their mass distribution and whether they are leaning correctly or not.

Master of Applied Science / The aim of this investigation was to investigate the effects of computer-based visual feedback in the teaching of singing. Pitch accuracy, a readily-measured parameter of the singing voice, was used in this study to gauge changes in singing for groups with and without visual feedback. The study investigated whether the style of feedback affects the amount of learning achieved, and whether the provision of concurrent visual feedback hampers the simultaneous performance of the singing task. The investigation used a baseline–intervention–post-test between-groups design. Participants of all skill levels were randomly assigned to a control group or one of two experimental groups – with all participants given one hour of singing training. At intervention, the two experimental groups were offered one of two different displays of real-time visual feedback on their vocal pitch accuracy, while control participants had a non-interactive display. All sessions were recorded, and the vocal exercise patterns performed at baseline, intervention and post-test phases were acoustically analysed for pitch accuracy. Questionnaires assessed both general health and the amount of singing and music training of all participants; people in the two experimental groups were also given a further questionnaire about the visual feedback. The results indicate that visual feedback improves pitch accuracy in singing. Cognitive load related to the decoding of visual information was a factor at intervention. At post-test, the two groups who had used real-time visual feedback demonstrated marked improvement on their initial pitch accuracy. There was no significant difference between the results of participants from the two experimental groups, although the participants with some background in singing training showed greater improvement using a simpler visual feedback design. The findings suggest that a hybrid approach integrating standard singing teaching practices with real-time visual feedback of aspects of the singing voice may improve learning.

HOLDERBAUM, G. G. Efeitos de diferentes tipos e freqüências de feedbacks visuais aumentados na aprendizagem dos seis fundamentos básicos do voleibol. Tese de Doutorado. Programa de Pós-Graduação em Ciências do Movimento Humano. Escola de Educação Física. Universidade Federal do Rio Grande do Sul, 2005. O voleibol é um dos esportes mais difundidos e praticados no mundo. No entanto, estudos que buscam o ampliar o conhecimento acerca do processo de ensino-aprendizagem dos fundamentos desta modalidade ainda são escassos. Talvez esta lacuna esteja relacionada com as dificuldades encontradas na construção de metodologias para o ensino do voleibol. Dessa forma, a utilização de feedback visual aumentado (FVA) parece ser adequada para o desenvolvimento deste esporte, uma vez que este recurso vem sendo apontado, já há algum tempo, na literatura como uma estratégia que pode influenciar o processo de ensino-aprendizagem de um gesto técnico esportivo. Tendo em vista a necessidade de novas estratégias bem como metodologias de ensino para o voleibol, o objetivo deste estudo foi verificar a influência de diferentes tipos e freqüências de FVAs no processo de ensino-aprendizagem dos seis fundamentos básicos do voleibol. Foram testados seis tipos diferentes de FVAs: (1) FVA-D (demonstrativo); (2) FVA-C (comparativo); (3) FVA-DI (demonstrativo com informações); (4) FVA-CI (comparativo com informações); (5) FVA-DIC (demonstrativo com informações e confirmação) e FVA-CIC (comparativo com informações e confirmação) combinados com quatro freqüências de fornecimento destes feedbacks: F50% (feedback a cada duas tentativas); F33% (feedback a cada três tentativas); F20% (feedback a cada cinco tentativas) e Fredu (feedback a F50% no 1º e 2º dias; a F33% no 3º e 4º dias e a F20% no quinto dia de prática). Participaram deste estudo 300 sujeitos de ambos os sexos, sem experiência em voleibol, estudantes de primeiro ano de ensino médio de escolas estaduais do município de Montenegro. Estes foram divididos em 24 grupos experimentais, ou seja, seis grupos de FVA para cada uma das quatro freqüências (n=12 em cada grupo) e grupo controle (n=12). O desenho experimental constou de três etapas: (1) período de pré-experimento, (2) sessões de prática e (3) período de pósexperimento. Este protocolo foi utilizado para o ensino de cada fundamento do voleibol: (1) saque, (2) passe, (3) levantamento, (4) ataque, (5) bloqueio e (6) defesa. Todos os grupos foram submetidos, em um primeiro momento, ao ensino do fundamento saque e ao final deste seguiu-se o mesmo protocolo para os demais fundamentos. Uma escala de pontuação específica foi desenvolvida para avaliar o desempenho dos grupos: Índice de desempenho (ID). O período de préexperimento constou de 10 tentativas de cada fundamento do voleibol. Nas sessões de prática foram realizadas 30 tentativas por dia, durante cinco dias. O período de pós-experimento foi dividido em três momentos: (1) pós-teste, (2) teste de transferência e (3) teste de retenção. O pós-teste foi realizado 24 horas após a última sessão de prática e constou dos mesmos procedimentos do préexperimento. O teste de transferência foi realizado 24 horas após o pós-teste e consistiu na execução do mesmo fundamento realizado nos períodos de avaliação, porém com alterações nas suas características. O teste de retenção foi realizado uma semana após o pós-teste e foi exatamente igual ao mesmo. Para análise dos resultados utilizou-se estatística descritiva (médias, desvios-padrão e coeficiente de variação). Estas medidas foram utilizadas para a comparação dos efeitos relativos às variáveis independentes (tipo de feedbacks, freqüência de feedback e momento). Os resultados mostraram que todos os tipos de FVA bem como todas as freqüências avaliadas apresentaram médias de ID superiores ao grupo controle em todas as comparações possíveis. A variação foi maior para o grupo controle em quase todas as comparações. Os grupos FVAs quando combinados com Fredu e F33% apresentaram resultados nas médias de ID muito próximos, embora maiores para a Fredu. Tanto a Fredu quanto a F33% apresentaram resultados consideravelmente melhores quando comparadas a F50% e a F20%. O grupo FVA-CIC apresentou as maiores médias de ID em todos os momentos avaliados. Este grupo também apresentou a menor variação na aprendizagem em quase todas as comparações possíveis. Os achados deste estudo mostraram que o FVA-CIC combinado com a freqüência reduzida apresenta-se como uma importante ferramenta no ensino dos seis fundamentos básicos do voleibol. / HOLDERBAUM, G. G. Effects of different types and frequency of visual augmented feedback on the learning of the six volleyball basic skills. Doctoral Dissertation. Human Movement Sciences Graduate Program. School of Physical Education. Federal University of Rio Grande do Sul, 2011. Volleyball is one of the most broadcast sports. However, there aren’t enough studies that investigate about the learning processes of volleyball skills. Perhaps, this gap is related to the difficulty found in the development of learning volleyball methodologies. Therefore, the use of visual augmented feedback (VAF) seems to be adequate to the improvement of this sport, since this resource has been noticed for a long time, in the literature with a strategy that can influence the learning processes of skill acquisition. Concerning the necessity of new strategies as well as methodologies in teaching volleyball, the aim of this study was to verify the influence of different types and frequencies of AVFs in the process of teaching-learning of the six basic volleyball skills. Six types of AVFs were tested: (1) AVF-D (demonstrative); (2) AVF-C (comparative); (3) AVF-DI (demonstrative with information); (4) AVF-CI (comparative with information); (5) AVF-DIC (demonstrative with information and confirmation); (6) AVF-CIC (comparative with information and confirmation) combined to four of these feedback frequencies: F50% (feedback after two trials); F33% (feedback after three trials); F20% (feedback after five trials) and Fredu (feedback the F50% in the 1st and 2nd days; the F33% in the 3rd and 4th days and the F20% in the 5th day of practice). Three hundred participants of both sex with no experience in volleyball took part in this study, with no experience in volleyball: junior high school students from public schools in Montenegro. These were divided in 24 experimental groups, that is, six groups of AVF to each one of the four frequencies (n=12 in each group) and the control group (n=12). The experimental design had three stages: (1) pre-experiment period; (2) practice sessions and (3) post-experimental period. This protocol was used to the teaching of each one of the volleyball basic skills: (1) serve, (2) pass, (3) set, (4) attack, (5) block and (6) defense. All groups were first submitted to the teaching of serve and in the end of this; the same was applied to the other skills. A specific score degrees was developed to evaluate the groups performance: performance index (PI). The preexperimental period was of 10 trials of each volleyball skills. In the practice sessions, 30 trials a day were done during five days. The post-experimental period was divided in three moments: (1) post-test, (2) transfer test and (3) retention test. The post-test was done 24 hours after the last practice sessions and had the same procedure as the pre-experimental. The transfer test was done 24 hours after the post-test and consisted in the accomplishment of the same skills realized in the evaluation period, but with some skill changings. The retention test was realized a week after the post-test and was exactly the same as it. Descriptive statistics was used for the results analysis (arithmetic mean, standard deviation and factor change). These measures were used to compare the effects related to the independent variable (types of feedbacks, feedback frequency and moment). The results showed that all AVF types as well as all the evaluated frequencies presented superior PI mean over the control group in every possible comparison. The variation was bigger to the control group in almost all comparisons. The AVF groups when combined to Fredu and F33% presented very closed results in the PI mean, although bigger to the Fredu. Fredu as much as F33% presented considerably better results when compared to F50% and F20%. The AVF-CIC presented the biggest PI mean in every evaluated moment. This group also presented the smallest variation in the learning in almost all possible comparisons. The findings of this study showed that the AVF-CIC combined to the reduced frequency is an important tool in the teaching of the six basic volleyball skills.

abstract: ABSTRACT The present studies investigated the separate effects of two types of visual feedback delay – increased latency and decreased updating rate – on performance – both actual (e.g. response time) and subjective (i.e. rating of perceived input device performance) – in 2-dimensional pointing tasks using a mouse as an input device. The first sub-study examined the effects of increased latency on performance using two separate experiments. In the first experiment the effects of constant latency on performance were tested, wherein participants completed blocks of trials with a constant level of latency. Additionally, after each block, participants rated their subjective experience of the input device performance at each level of latency. The second experiment examined the effects of variable latency on performance, where latency was randomized within blocks of trials. The second sub-study investigated the effects of decreased updating rates on performance in the same manner as the first study, wherein experiment one tested the effect of constant updating rate on performance as well as subjective rating, and experiment two tested the effect of variable updating rate on performance. The findings suggest that latency is negative correlated with actual performance as well as subjective ratings of performance, and updating rate is positively correlated with actual performance as well as subjective ratings of performance. / Dissertation/Thesis / Masters Thesis Applied Psychology 2015

HOLDERBAUM, G. G. Efeitos de diferentes tipos e freqüências de feedbacks visuais aumentados na aprendizagem dos seis fundamentos básicos do voleibol. Tese de Doutorado. Programa de Pós-Graduação em Ciências do Movimento Humano. Escola de Educação Física. Universidade Federal do Rio Grande do Sul, 2005. O voleibol é um dos esportes mais difundidos e praticados no mundo. No entanto, estudos que buscam o ampliar o conhecimento acerca do processo de ensino-aprendizagem dos fundamentos desta modalidade ainda são escassos. Talvez esta lacuna esteja relacionada com as dificuldades encontradas na construção de metodologias para o ensino do voleibol. Dessa forma, a utilização de feedback visual aumentado (FVA) parece ser adequada para o desenvolvimento deste esporte, uma vez que este recurso vem sendo apontado, já há algum tempo, na literatura como uma estratégia que pode influenciar o processo de ensino-aprendizagem de um gesto técnico esportivo. Tendo em vista a necessidade de novas estratégias bem como metodologias de ensino para o voleibol, o objetivo deste estudo foi verificar a influência de diferentes tipos e freqüências de FVAs no processo de ensino-aprendizagem dos seis fundamentos básicos do voleibol. Foram testados seis tipos diferentes de FVAs: (1) FVA-D (demonstrativo); (2) FVA-C (comparativo); (3) FVA-DI (demonstrativo com informações); (4) FVA-CI (comparativo com informações); (5) FVA-DIC (demonstrativo com informações e confirmação) e FVA-CIC (comparativo com informações e confirmação) combinados com quatro freqüências de fornecimento destes feedbacks: F50% (feedback a cada duas tentativas); F33% (feedback a cada três tentativas); F20% (feedback a cada cinco tentativas) e Fredu (feedback a F50% no 1º e 2º dias; a F33% no 3º e 4º dias e a F20% no quinto dia de prática). Participaram deste estudo 300 sujeitos de ambos os sexos, sem experiência em voleibol, estudantes de primeiro ano de ensino médio de escolas estaduais do município de Montenegro. Estes foram divididos em 24 grupos experimentais, ou seja, seis grupos de FVA para cada uma das quatro freqüências (n=12 em cada grupo) e grupo controle (n=12). O desenho experimental constou de três etapas: (1) período de pré-experimento, (2) sessões de prática e (3) período de pósexperimento. Este protocolo foi utilizado para o ensino de cada fundamento do voleibol: (1) saque, (2) passe, (3) levantamento, (4) ataque, (5) bloqueio e (6) defesa. Todos os grupos foram submetidos, em um primeiro momento, ao ensino do fundamento saque e ao final deste seguiu-se o mesmo protocolo para os demais fundamentos. Uma escala de pontuação específica foi desenvolvida para avaliar o desempenho dos grupos: Índice de desempenho (ID). O período de préexperimento constou de 10 tentativas de cada fundamento do voleibol. Nas sessões de prática foram realizadas 30 tentativas por dia, durante cinco dias. O período de pós-experimento foi dividido em três momentos: (1) pós-teste, (2) teste de transferência e (3) teste de retenção. O pós-teste foi realizado 24 horas após a última sessão de prática e constou dos mesmos procedimentos do préexperimento. O teste de transferência foi realizado 24 horas após o pós-teste e consistiu na execução do mesmo fundamento realizado nos períodos de avaliação, porém com alterações nas suas características. O teste de retenção foi realizado uma semana após o pós-teste e foi exatamente igual ao mesmo. Para análise dos resultados utilizou-se estatística descritiva (médias, desvios-padrão e coeficiente de variação). Estas medidas foram utilizadas para a comparação dos efeitos relativos às variáveis independentes (tipo de feedbacks, freqüência de feedback e momento). Os resultados mostraram que todos os tipos de FVA bem como todas as freqüências avaliadas apresentaram médias de ID superiores ao grupo controle em todas as comparações possíveis. A variação foi maior para o grupo controle em quase todas as comparações. Os grupos FVAs quando combinados com Fredu e F33% apresentaram resultados nas médias de ID muito próximos, embora maiores para a Fredu. Tanto a Fredu quanto a F33% apresentaram resultados consideravelmente melhores quando comparadas a F50% e a F20%. O grupo FVA-CIC apresentou as maiores médias de ID em todos os momentos avaliados. Este grupo também apresentou a menor variação na aprendizagem em quase todas as comparações possíveis. Os achados deste estudo mostraram que o FVA-CIC combinado com a freqüência reduzida apresenta-se como uma importante ferramenta no ensino dos seis fundamentos básicos do voleibol. / HOLDERBAUM, G. G. Effects of different types and frequency of visual augmented feedback on the learning of the six volleyball basic skills. Doctoral Dissertation. Human Movement Sciences Graduate Program. School of Physical Education. Federal University of Rio Grande do Sul, 2011. Volleyball is one of the most broadcast sports. However, there aren’t enough studies that investigate about the learning processes of volleyball skills. Perhaps, this gap is related to the difficulty found in the development of learning volleyball methodologies. Therefore, the use of visual augmented feedback (VAF) seems to be adequate to the improvement of this sport, since this resource has been noticed for a long time, in the literature with a strategy that can influence the learning processes of skill acquisition. Concerning the necessity of new strategies as well as methodologies in teaching volleyball, the aim of this study was to verify the influence of different types and frequencies of AVFs in the process of teaching-learning of the six basic volleyball skills. Six types of AVFs were tested: (1) AVF-D (demonstrative); (2) AVF-C (comparative); (3) AVF-DI (demonstrative with information); (4) AVF-CI (comparative with information); (5) AVF-DIC (demonstrative with information and confirmation); (6) AVF-CIC (comparative with information and confirmation) combined to four of these feedback frequencies: F50% (feedback after two trials); F33% (feedback after three trials); F20% (feedback after five trials) and Fredu (feedback the F50% in the 1st and 2nd days; the F33% in the 3rd and 4th days and the F20% in the 5th day of practice). Three hundred participants of both sex with no experience in volleyball took part in this study, with no experience in volleyball: junior high school students from public schools in Montenegro. These were divided in 24 experimental groups, that is, six groups of AVF to each one of the four frequencies (n=12 in each group) and the control group (n=12). The experimental design had three stages: (1) pre-experiment period; (2) practice sessions and (3) post-experimental period. This protocol was used to the teaching of each one of the volleyball basic skills: (1) serve, (2) pass, (3) set, (4) attack, (5) block and (6) defense. All groups were first submitted to the teaching of serve and in the end of this; the same was applied to the other skills. A specific score degrees was developed to evaluate the groups performance: performance index (PI). The preexperimental period was of 10 trials of each volleyball skills. In the practice sessions, 30 trials a day were done during five days. The post-experimental period was divided in three moments: (1) post-test, (2) transfer test and (3) retention test. The post-test was done 24 hours after the last practice sessions and had the same procedure as the pre-experimental. The transfer test was done 24 hours after the post-test and consisted in the accomplishment of the same skills realized in the evaluation period, but with some skill changings. The retention test was realized a week after the post-test and was exactly the same as it. Descriptive statistics was used for the results analysis (arithmetic mean, standard deviation and factor change). These measures were used to compare the effects related to the independent variable (types of feedbacks, feedback frequency and moment). The results showed that all AVF types as well as all the evaluated frequencies presented superior PI mean over the control group in every possible comparison. The variation was bigger to the control group in almost all comparisons. The AVF groups when combined to Fredu and F33% presented very closed results in the PI mean, although bigger to the Fredu. Fredu as much as F33% presented considerably better results when compared to F50% and F20%. The AVF-CIC presented the biggest PI mean in every evaluated moment. This group also presented the smallest variation in the learning in almost all possible comparisons. The findings of this study showed that the AVF-CIC combined to the reduced frequency is an important tool in the teaching of the six basic volleyball skills.

HOLDERBAUM, G. G. Efeitos de diferentes tipos e freqüências de feedbacks visuais aumentados na aprendizagem dos seis fundamentos básicos do voleibol. Tese de Doutorado. Programa de Pós-Graduação em Ciências do Movimento Humano. Escola de Educação Física. Universidade Federal do Rio Grande do Sul, 2005. O voleibol é um dos esportes mais difundidos e praticados no mundo. No entanto, estudos que buscam o ampliar o conhecimento acerca do processo de ensino-aprendizagem dos fundamentos desta modalidade ainda são escassos. Talvez esta lacuna esteja relacionada com as dificuldades encontradas na construção de metodologias para o ensino do voleibol. Dessa forma, a utilização de feedback visual aumentado (FVA) parece ser adequada para o desenvolvimento deste esporte, uma vez que este recurso vem sendo apontado, já há algum tempo, na literatura como uma estratégia que pode influenciar o processo de ensino-aprendizagem de um gesto técnico esportivo. Tendo em vista a necessidade de novas estratégias bem como metodologias de ensino para o voleibol, o objetivo deste estudo foi verificar a influência de diferentes tipos e freqüências de FVAs no processo de ensino-aprendizagem dos seis fundamentos básicos do voleibol. Foram testados seis tipos diferentes de FVAs: (1) FVA-D (demonstrativo); (2) FVA-C (comparativo); (3) FVA-DI (demonstrativo com informações); (4) FVA-CI (comparativo com informações); (5) FVA-DIC (demonstrativo com informações e confirmação) e FVA-CIC (comparativo com informações e confirmação) combinados com quatro freqüências de fornecimento destes feedbacks: F50% (feedback a cada duas tentativas); F33% (feedback a cada três tentativas); F20% (feedback a cada cinco tentativas) e Fredu (feedback a F50% no 1º e 2º dias; a F33% no 3º e 4º dias e a F20% no quinto dia de prática). Participaram deste estudo 300 sujeitos de ambos os sexos, sem experiência em voleibol, estudantes de primeiro ano de ensino médio de escolas estaduais do município de Montenegro. Estes foram divididos em 24 grupos experimentais, ou seja, seis grupos de FVA para cada uma das quatro freqüências (n=12 em cada grupo) e grupo controle (n=12). O desenho experimental constou de três etapas: (1) período de pré-experimento, (2) sessões de prática e (3) período de pósexperimento. Este protocolo foi utilizado para o ensino de cada fundamento do voleibol: (1) saque, (2) passe, (3) levantamento, (4) ataque, (5) bloqueio e (6) defesa. Todos os grupos foram submetidos, em um primeiro momento, ao ensino do fundamento saque e ao final deste seguiu-se o mesmo protocolo para os demais fundamentos. Uma escala de pontuação específica foi desenvolvida para avaliar o desempenho dos grupos: Índice de desempenho (ID). O período de préexperimento constou de 10 tentativas de cada fundamento do voleibol. Nas sessões de prática foram realizadas 30 tentativas por dia, durante cinco dias. O período de pós-experimento foi dividido em três momentos: (1) pós-teste, (2) teste de transferência e (3) teste de retenção. O pós-teste foi realizado 24 horas após a última sessão de prática e constou dos mesmos procedimentos do préexperimento. O teste de transferência foi realizado 24 horas após o pós-teste e consistiu na execução do mesmo fundamento realizado nos períodos de avaliação, porém com alterações nas suas características. O teste de retenção foi realizado uma semana após o pós-teste e foi exatamente igual ao mesmo. Para análise dos resultados utilizou-se estatística descritiva (médias, desvios-padrão e coeficiente de variação). Estas medidas foram utilizadas para a comparação dos efeitos relativos às variáveis independentes (tipo de feedbacks, freqüência de feedback e momento). Os resultados mostraram que todos os tipos de FVA bem como todas as freqüências avaliadas apresentaram médias de ID superiores ao grupo controle em todas as comparações possíveis. A variação foi maior para o grupo controle em quase todas as comparações. Os grupos FVAs quando combinados com Fredu e F33% apresentaram resultados nas médias de ID muito próximos, embora maiores para a Fredu. Tanto a Fredu quanto a F33% apresentaram resultados consideravelmente melhores quando comparadas a F50% e a F20%. O grupo FVA-CIC apresentou as maiores médias de ID em todos os momentos avaliados. Este grupo também apresentou a menor variação na aprendizagem em quase todas as comparações possíveis. Os achados deste estudo mostraram que o FVA-CIC combinado com a freqüência reduzida apresenta-se como uma importante ferramenta no ensino dos seis fundamentos básicos do voleibol. / HOLDERBAUM, G. G. Effects of different types and frequency of visual augmented feedback on the learning of the six volleyball basic skills. Doctoral Dissertation. Human Movement Sciences Graduate Program. School of Physical Education. Federal University of Rio Grande do Sul, 2011. Volleyball is one of the most broadcast sports. However, there aren’t enough studies that investigate about the learning processes of volleyball skills. Perhaps, this gap is related to the difficulty found in the development of learning volleyball methodologies. Therefore, the use of visual augmented feedback (VAF) seems to be adequate to the improvement of this sport, since this resource has been noticed for a long time, in the literature with a strategy that can influence the learning processes of skill acquisition. Concerning the necessity of new strategies as well as methodologies in teaching volleyball, the aim of this study was to verify the influence of different types and frequencies of AVFs in the process of teaching-learning of the six basic volleyball skills. Six types of AVFs were tested: (1) AVF-D (demonstrative); (2) AVF-C (comparative); (3) AVF-DI (demonstrative with information); (4) AVF-CI (comparative with information); (5) AVF-DIC (demonstrative with information and confirmation); (6) AVF-CIC (comparative with information and confirmation) combined to four of these feedback frequencies: F50% (feedback after two trials); F33% (feedback after three trials); F20% (feedback after five trials) and Fredu (feedback the F50% in the 1st and 2nd days; the F33% in the 3rd and 4th days and the F20% in the 5th day of practice). Three hundred participants of both sex with no experience in volleyball took part in this study, with no experience in volleyball: junior high school students from public schools in Montenegro. These were divided in 24 experimental groups, that is, six groups of AVF to each one of the four frequencies (n=12 in each group) and the control group (n=12). The experimental design had three stages: (1) pre-experiment period; (2) practice sessions and (3) post-experimental period. This protocol was used to the teaching of each one of the volleyball basic skills: (1) serve, (2) pass, (3) set, (4) attack, (5) block and (6) defense. All groups were first submitted to the teaching of serve and in the end of this; the same was applied to the other skills. A specific score degrees was developed to evaluate the groups performance: performance index (PI). The preexperimental period was of 10 trials of each volleyball skills. In the practice sessions, 30 trials a day were done during five days. The post-experimental period was divided in three moments: (1) post-test, (2) transfer test and (3) retention test. The post-test was done 24 hours after the last practice sessions and had the same procedure as the pre-experimental. The transfer test was done 24 hours after the post-test and consisted in the accomplishment of the same skills realized in the evaluation period, but with some skill changings. The retention test was realized a week after the post-test and was exactly the same as it. Descriptive statistics was used for the results analysis (arithmetic mean, standard deviation and factor change). These measures were used to compare the effects related to the independent variable (types of feedbacks, feedback frequency and moment). The results showed that all AVF types as well as all the evaluated frequencies presented superior PI mean over the control group in every possible comparison. The variation was bigger to the control group in almost all comparisons. The AVF groups when combined to Fredu and F33% presented very closed results in the PI mean, although bigger to the Fredu. Fredu as much as F33% presented considerably better results when compared to F50% and F20%. The AVF-CIC presented the biggest PI mean in every evaluated moment. This group also presented the smallest variation in the learning in almost all possible comparisons. The findings of this study showed that the AVF-CIC combined to the reduced frequency is an important tool in the teaching of the six basic volleyball skills.

Robots are required in many jobs. The jobs related to tele-operation may be very challenging and often require reaching a destination quickly and with minimum collisions. In order to succeed in these jobs, human operators are asked to tele-operate a robot manually through a user interface. The design of a user interface and of the information provided in it, become therefore critical elements for the successful completion of robot tele-operation tasks. Effective and timely robot tele-navigation mainly relies on the intuitiveness provided by the interface and on the richness and presentation of the feedback given. This project investigated the use of both haptic and visual feedbacks in a user interface for robot tele-navigation. The aim was to overcome some of the limitations observed in a state of the art works, turning what is sometimes described as contrasting into an added value to improve tele-navigation performance. The key issue is to combine different human sensory modalities in a coherent way and to benefit from 3-D vision too. The proposed new approach was inspired by how visually impaired people use walking sticks to navigate. Haptic feedback may provide helpful input to a user to comprehend distances to surrounding obstacles and information about the obstacle distribution. This was proposed to be achieved entirely relying on on-board range sensors, and by processing this input through a simple scheme that regulates magnitude and direction of the environmental force-feedback provided to the haptic device. A specific algorithm was also used to render the distribution of very close objects to provide appropriate touch sensations. Scene visualization was provided by the system and it was shown to a user coherently to haptic sensation. Different visualization configurations, from multi-viewpoint observation to 3-D visualization, were proposed and rigorously assessed through experimentations, to understand the advantages of the proposed approach and performance variations among different 3-D display technologies. Over twenty users were invited to participate in a usability study composed by two major experiments. The first experiment focused on a comparison between the proposed haptic-feedback strategy and a typical state of the art approach. It included testing with a multi-viewpoint visual observation. The second experiment investigated the performance of the proposed haptic-feedback strategy when combined with three different stereoscopic-3D visualization technologies. The results from the experiments were encouraging and showed good performance with the proposed approach and an improvement over literature approaches to haptic feedback in robot tele-operation. It was also demonstrated that 3-D visualization can be beneficial for robot tele-navigation and it will not contrast with haptic feedback if it is properly aligned to it. Performance may vary with different 3-D visualization technologies, which is also discussed in the presented work.