61 |
Afraid to lose: The fear of falling's effect on white-collar crimeKodatt, Zachary Hayes 01 August 2016 (has links)
This study examined the potential moderating effects that the fear of falling may have on potential white-collar crime perpetrators using rational choice and differential association theory perspectives. A self-report, factorial survey measurement tool utilizing three hypothetical vignettes placing respondents in a business situation with the potential to commit insider trading was given to 612 students at a Midwestern university. Results indicate that the fear of falling had no moderating effects, differential association theory was partially supported in Vignette 1, and rational choice theory was partially supported across all three vignettes.
|
62 |
Prevalência do medo de quedas em idosos e sua associação com fatores clínicos,funcionais e psicossociais: Estudo FIBRA-RJ / Prevalence of fear of falling in the elderly and its association with clinical, functional and psychosocial factors: FIBRA-RJ studyFlávia Moura Malini 25 February 2014 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Introdução: Com o expressivo aumento da população idosa, as quedas são eventos comuns e levam a desfechos adversos à saúde. As consequências do medo de quedas podem ser tão incapacitantes como as quedas. Objetivo: O presente estudo
teve como objetivo estimar a prevalência do medo de quedas em idosos e sua associação com fatores clínicos, funcionais e psicossociais. Métodos: Utilizaram-se os dados do Estudo FIBRA-RJ, que avaliou clientes de uma operadora de saúde,
residentes na Zona Norte do município do Rio de Janeiro. A seleção desta amostra foi realizada através de amostragem aleatória inversa, de acordo com estratos de faixa etária e sexo do cadastro oferecido pela operadora. As entrevistas foram realizadas face a face no domicilio. O medo de quedas, variável dependente, foi avaliado através da FES-I-BR. As seguintes variáveis clínicas, funcionais e psicossociais foram avaliadas como variáveis independentes: histórico de quedas,
fratura pós-queda, número de comorbidades, número de medicamentos, internação no último ano, uso de dispositivo de auxílio à marcha, dependência funcional nas atividades básicas e instrumentais de vida diária, dificuldade visual e auditiva, força de preensão palmar, velocidade de marcha, autopercepção de saúde, sintomas depressivos, alteração cognitiva, morar só, apoio social instrumental e nível de atividade. As associações foram avaliadas através de regressão logística. Resultados: Dentre os 742 idosos avaliados, 51,9% apresentaram medo de quedas,
sendo esta prevalência maior no sexo feminino e nos mais idosos. Na análise logística multivariada, houve associação com histórico de 1 ou 2 quedas (OR=2,18; IC95%1,42-3,36), 3 ou mais quedas (OR=2,72; IC95% 1,10-6,70), usar 7 ou mais
medicamentos (OR=1,70; IC95%1,04-2,80), dificuldade auditiva (OR=1,66; IC95% 1,10-2,49), ter dependência funcional nas atividades de vida diária (AVDs) (OR=1,73; IC95%1,07-2,79), velocidade de marcha diminuída (OR=1,64;
IC95%1,04-2,58), autopercepção de saúde regular (OR=1,89; IC95%1,30-2,74) e ruim/muito ruim (OR=4,92; IC95%1,49-16,27) e sintomas depressivos (OR=1,68; IC95%1,07-2,63). Conclusão: Os resultados obtidos mostram a prevalência elevada de medo de quedas. Destaca-se a necessidade de avaliação desta condição nos idosos. Identificar os fatores associados é útil para desenvolver estratégias efetivas de intervenção dos possíveis fatores modificáveis. / Introduction: With the significant increase in the elderly population, falls are common events and lead to adverse health outcomes. The consequences of fear of falling can be as disabling as the falls. Objective: This study aimed to determine the prevalence of fear of falling in elderly and its association with clinical, functional, and psychosocial factors. Methods: We used data from FIBRA-RJ study, who evaluated
customers of a private health provider, aged 65 or older, residing in the northern of Rio de Janeiro city. Fear of falling was measured by the Falls Efficacy Scale-I-BR (FES-I-BR).The following independents variables were assessed: history of falls, fracture post fall, number of comorbidities, number of medications, hospitalization in the previous year, use of walking aid, functional dependency in activities of daily living and instrumental activities of daily living, visual and auditive impaiment, grip strength, walking speed, self-rated health, depressive symptoms, cognitive impairment, living alone, social support and activity level. To evaluate these associations, multiple logistic regression were used. Results: Among the 742
assessed elderly, 51.9% had fear of falling, which were more prevalente in women and with increase age. Was associated with fear of falling: a history of 1 or 2 falls (OR=2.18; IC 95%1.42-3.36), 3 or more falls (OR=2.72; IC95% 1.10-6.70), use of 7 or more drugs (OR=1.70; IC95%1.04-2.80), hearing impairment (OR=1.66; IC95%1.10- 2.49), functional dependence in activities of daily living (ADL) (OR=1.73; IC95%1,07-2,79), gait speed decreased (OR=1.64; IC 95%1.04-2.58), self-rated health regular (OR=1.89; IC 95%1.30-2.74) and poor / very poor (OR=4.92; IC95%1.49-16.27) and depressive symptoms (OR=1.68; IC95%1.07-2.63). Conclusion: The obtained results show a high prevalence of fear of falling in this sample. We highlight the need for the assessment of this condition in the elderly in order to identify these individuals earlier to develop effective intervention strategies of modifiable factors.
|
63 |
Effusum et deiectum: o tratamento no Código Civil e sua origem no direito romano / Effusum et deiectum: the treatment in the civil code and the orgin in the Roman rightPaula Espindola Bulamarque Moreira 28 May 2010 (has links)
Esse estudo tem por escopo a análise da responsabilidade pelas coisas caídas, estabelecida no artigo 938 do Código Civil, e sua comparação em relação ao quase-delito romano effusum et deiectum. Inicia-se tal estudo com a demonstração das categorias de quase-delitos em Roma, explicando-se cada uma delas e sua localização no Digesto. Nos capítulos seguintes faz-se uma análise da responsabilidade civil, mencionando-se sua evolução, conceito atual, bem como suas principais classificações em nosso atual ordenamento, enfatizando-se a responsabilidade pelas coisas caídas ou lançadas. Realiza-se, então, uma comparação entre esta última modalidade de responsabilidade, presente no artigo 938 do Código Civil, e o tratamento do quase-delito romano effusum et deiectum durante o período clássico. Ao final, conclui-se que o artigo do Código Civil retromencionado tem sua origem no citado quase-delito romano, em virtude da patente semelhança entre ambos, malgrado o grande lapso temporal que os separa. / The objective of this study is the analysis of the responsibility for the falling things, established in the article 938 of the Civil Code, and the comparison between this article and the roman quasi-delicti effusum et deiectum. This study begins with the demonstration of the categories of quasi-delicti in Roma, explaining each one of them and their localization in the Digesto. In the following chapters, there is an analysis of the civil responsibility, mentioning its evolution, actual concept, and the main classifications in our ordainment, emphasizing the responsibility for falling things. After that, a comparison was made between this last modality of responsibility, mentioned in the article 938 of the Civil Code, and the treatment of the roman quasi-delict in the classic period. At the end, we concluded that the origin of the article 938 of the Civil Code is the cited roman quasi-delicti, because of their likeness, despite the time gap between them.
|
64 |
Risco de quedas: intervenções de enfermagem da NIC identificadas por enfermeiros mexicanos a pacientes hospitalizados / Fall Risks. NIC identified Mexican nursing interventions to hospitalized patientsDolores Eunice Hernandez Herrera 13 June 2012 (has links)
Trata-se de estudo descritivo, com o objetivo de analisar a aplicabilidade de intervenções da NIC, para situações de Risco de Quedas em pacientes hospitalizados por meio do mapeamento cruzado. Participaram do estudo 10 enfermeiros que atuam na Clínica Médica de um Hospital Geral Regional de segundo porte na cidade de Querétaro, Qro., México. O estudo foi realizado em três etapas; na primeira, foram descritas pelos enfermeiros quais atividades eram realizadas para os pacientes com risco de quedas. Na segunda etapa, foi realizado o mapeamento cruzado das atividades e das intervenções da NIC para o diagnóstico Risco de quedas pela pesquisadora. Na terceira etapa, foi realizado o refinamento do mapeamento comparativo por enfermeiros expertos e a NIC com as Intervenções identificadas pela pesquisadora. Quanto aos resultados, dos 10 enfermeiros nove eram sexo feminino, com idade entre 31 e 40 anos e com experiência no trabalho com média de sete anos e meio. Foram citadas 173 atividades para Risco de quedas pelos enfermeiros que participaram no estudo. Já no mapeamento cruzado, foram listadas 14 intervenções e 70 atividades das quais seis intervenções estavam no Domínio Segurança com 40 atividades, quatro intervenções no Domínio Fisiológico Básico com 20 atividades e duas intervenções no Domínio Fisiológico Complexo com 10 atividades. Além das atividades propostas na ligação NANDA/NIC foram mapeadas duas intervenções não propostas nessa ligação, mas citadas na NIC - Contenção Física e Identificação do Risco - nomeadas pelos enfermeiros como realizadas junto aos pacientes com Risco de quedas. As intervenções que tiveram o maior numero de atividades mapeadas foram principalmente às relacionadas com o Domínio de Segurança. Estas intervenções mapeadas mostram o atuar dos enfermeiros e sua contribuição na prevenção de quedas. Os achados do estudo poderão ser empregados para desenvolver programas, políticas e estratégias que contribuam para segurança do paciente, por meio do das taxonomias, no contexto da enfermagem mexicana. / This is a descriptive study which main objective is to analyze the feasibility of NIC interventions on falling risk situations among hospitalized patients through cross mapping method. During this study, ten Intern Medicine Service nurses from a second level hospital in Queretaro City, Mexico participated. The study was designed into three stages. At first stage, there were described the activities made by nurses with falling risk patients. At second stage, there was made a cross mapping from NIC\'s activities and interventions for the falls risk diagnosis of the researcher. At third stage, a comparative fine tuning mapping was made among expert nurses and the NIC compared with the identified interventions from the researcher. The results of the research were as follows: From ten nurses, nine were 31 to 40 year old female with an average working experience of seven years and a half. There were mentioned 173 falls risk activities by nurses who attended the study. There were listed 14 interventions and 70 activities on the cross mapping from which six interventions were on the Security Dominion with 40 activities, six interventions were on the Basic Physiological Dominion with 20 activities and two interventions were on the Complex Physiological Dominion with 10 activities. On the NANDA/INC interrelations activities were mapped two non-proposed interventions in the Restraint Physical and Risk Identification mentioned by nurses during their attendance with falling risk patients. The higher number of mapped intervention activities were of the Security Dominion. This mapped interventions show the contribution of nurses toward falls prevention. Current results of this study may contribute to the creation of prevention programs, politics and strategies which enhance patient\'s security through taxonomy\'s usage within the Mexican nursing context.
|
65 |
Prevalência do medo de quedas em idosos e sua associação com fatores clínicos,funcionais e psicossociais: Estudo FIBRA-RJ / Prevalence of fear of falling in the elderly and its association with clinical, functional and psychosocial factors: FIBRA-RJ studyFlávia Moura Malini 25 February 2014 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Introdução: Com o expressivo aumento da população idosa, as quedas são eventos comuns e levam a desfechos adversos à saúde. As consequências do medo de quedas podem ser tão incapacitantes como as quedas. Objetivo: O presente estudo
teve como objetivo estimar a prevalência do medo de quedas em idosos e sua associação com fatores clínicos, funcionais e psicossociais. Métodos: Utilizaram-se os dados do Estudo FIBRA-RJ, que avaliou clientes de uma operadora de saúde,
residentes na Zona Norte do município do Rio de Janeiro. A seleção desta amostra foi realizada através de amostragem aleatória inversa, de acordo com estratos de faixa etária e sexo do cadastro oferecido pela operadora. As entrevistas foram realizadas face a face no domicilio. O medo de quedas, variável dependente, foi avaliado através da FES-I-BR. As seguintes variáveis clínicas, funcionais e psicossociais foram avaliadas como variáveis independentes: histórico de quedas,
fratura pós-queda, número de comorbidades, número de medicamentos, internação no último ano, uso de dispositivo de auxílio à marcha, dependência funcional nas atividades básicas e instrumentais de vida diária, dificuldade visual e auditiva, força de preensão palmar, velocidade de marcha, autopercepção de saúde, sintomas depressivos, alteração cognitiva, morar só, apoio social instrumental e nível de atividade. As associações foram avaliadas através de regressão logística. Resultados: Dentre os 742 idosos avaliados, 51,9% apresentaram medo de quedas,
sendo esta prevalência maior no sexo feminino e nos mais idosos. Na análise logística multivariada, houve associação com histórico de 1 ou 2 quedas (OR=2,18; IC95%1,42-3,36), 3 ou mais quedas (OR=2,72; IC95% 1,10-6,70), usar 7 ou mais
medicamentos (OR=1,70; IC95%1,04-2,80), dificuldade auditiva (OR=1,66; IC95% 1,10-2,49), ter dependência funcional nas atividades de vida diária (AVDs) (OR=1,73; IC95%1,07-2,79), velocidade de marcha diminuída (OR=1,64;
IC95%1,04-2,58), autopercepção de saúde regular (OR=1,89; IC95%1,30-2,74) e ruim/muito ruim (OR=4,92; IC95%1,49-16,27) e sintomas depressivos (OR=1,68; IC95%1,07-2,63). Conclusão: Os resultados obtidos mostram a prevalência elevada de medo de quedas. Destaca-se a necessidade de avaliação desta condição nos idosos. Identificar os fatores associados é útil para desenvolver estratégias efetivas de intervenção dos possíveis fatores modificáveis. / Introduction: With the significant increase in the elderly population, falls are common events and lead to adverse health outcomes. The consequences of fear of falling can be as disabling as the falls. Objective: This study aimed to determine the prevalence of fear of falling in elderly and its association with clinical, functional, and psychosocial factors. Methods: We used data from FIBRA-RJ study, who evaluated
customers of a private health provider, aged 65 or older, residing in the northern of Rio de Janeiro city. Fear of falling was measured by the Falls Efficacy Scale-I-BR (FES-I-BR).The following independents variables were assessed: history of falls, fracture post fall, number of comorbidities, number of medications, hospitalization in the previous year, use of walking aid, functional dependency in activities of daily living and instrumental activities of daily living, visual and auditive impaiment, grip strength, walking speed, self-rated health, depressive symptoms, cognitive impairment, living alone, social support and activity level. To evaluate these associations, multiple logistic regression were used. Results: Among the 742
assessed elderly, 51.9% had fear of falling, which were more prevalente in women and with increase age. Was associated with fear of falling: a history of 1 or 2 falls (OR=2.18; IC 95%1.42-3.36), 3 or more falls (OR=2.72; IC95% 1.10-6.70), use of 7 or more drugs (OR=1.70; IC95%1.04-2.80), hearing impairment (OR=1.66; IC95%1.10- 2.49), functional dependence in activities of daily living (ADL) (OR=1.73; IC95%1,07-2,79), gait speed decreased (OR=1.64; IC 95%1.04-2.58), self-rated health regular (OR=1.89; IC 95%1.30-2.74) and poor / very poor (OR=4.92; IC95%1.49-16.27) and depressive symptoms (OR=1.68; IC95%1.07-2.63). Conclusion: The obtained results show a high prevalence of fear of falling in this sample. We highlight the need for the assessment of this condition in the elderly in order to identify these individuals earlier to develop effective intervention strategies of modifiable factors.
|
66 |
Avaliação da inversão da sacarose em um sistema de evaporação (evaporador de filme descendente com promotor de película). / Evaluation of the sugar inversion in an evaporation system (faling film evaporator with promotor of film).Edwin José Castillo Zurita 17 June 2008 (has links)
Neste trabalho é apresentada a avaliação da inversão da sacarose em um sistema constituído de um Evaporador de filme descendente com promotor de película. Foi feita a modelagem da inversão considerando-se os balanços de massa e de entalpia e a cinética de inversão no tubo de evaporação. Os principais parâmetros considerados foram: constante cinética (k), taxa de evaporação(mv), concentração de açúcares totais (C), vazão do líquido no tubo de evaporação (q), pH, temperatura (T) e tempo de residência no tubo de evaporação (T). Usaram-se dois métodos para a resolução do modelo, a primeira através da integração numérica do modelo (Runge Kutta de 4ta ordem) e a outra através de equacionamento simplificado a partir valores médios das propriedades, pH, e calculando as constantes cinéticas nas temperaturas efetivas em cada zona do tubo de evaporação, Tefa (zona de aquecimento) e Tefe (zona de evaporação), possibilitando assim, a integração analítica do modelo. Foram calculados os valores do volume do líquido (V) através dos dois métodos. Os resultados foram expressos em função da vazão do líquido (q). Verificou-se que os resultados calculados pelos dois métodos foram muito próximos. Os modelos desenvolvidos podem ser aplicados para a otimização do processo de evaporação visando à minimização da inversão da sacarose. O método desenvolvido possibilita a determinação do tempo de residência no tubo de evaporação. / In this work the evaluation of sucrose inversion in a system formed by falling film Evaporator with Promoter of film is presented. The modeling was made considering: mass and enthalpy balances and the kinetic of inversion in the evaporation tube. The mean parameters investigated were: kinetic constant (k), evaporation rate (mv), concentration of total sugars (C), volumetric velocity of the liquid in the evaporation tube (q), pH, temperature (T) and residence time in the evaporation tube (T). Two methods was used to solve the model, the first by numeric integration (Runge Kutta 4th Order) and the other by analytic integration of simplified model considering mean values of properties and pH, and the kinetic constant calculates at effective temperatures in each zone of the evaporation tube, Tefa and Tefe, allowed the analytic integration of the model. The volume of liquid in the evaporation tube (V) was calculated by the two methods (numeric integration and simplified methods). The results were expressed as a function of liquid flow rate (q). It was verified that the values obtained by the two methods were very closed. These models can be used for the optimization of the evaporation process emphasizing the minimization of the sucrose inversion. The methodology could be used for the determination of the residence time in the evaporation tube.
|
67 |
Medo de quedas em idosos do Núcleo da Unidade Básica de Saúde João da Silva VizellaSantos, Jéssica Janete Novais January 2012 (has links)
Submitted by Fabiana Gonçalves Pinto (benf@ndc.uff.br) on 2015-12-04T15:52:52Z
No. of bitstreams: 1
Jessica Janete Novais Santos.pdf: 1230062 bytes, checksum: 7010840151e0bca98cee207f12500ce1 (MD5) / Made available in DSpace on 2015-12-04T15:52:52Z (GMT). No. of bitstreams: 1
Jessica Janete Novais Santos.pdf: 1230062 bytes, checksum: 7010840151e0bca98cee207f12500ce1 (MD5)
Previous issue date: 2012 / Mestrado Acadêmico em Ciências do Cuidado em Saúde / O envelhecimento da população brasileira, recebeu influências do fenômeno da transição demográfica e a partir dos dados censitários disponíveis já encontramos números semelhantes ao de países desenvolvidos. Com isto aumentaram as preocupações com as comorbidades. As quedas dos idosos são consideradas como um dos grandes problemas dos que envelhecem e investigar as quedas dos idosos foi a proposta deste estudo que investigou os idosos que frequentavam as oficinas propostas no projeto Vida Saudável que ocorreram na Unidade Básica de Saúde João da Silva Vizella. A literatura indica como preditor de queda o medo que as mesmas causam, que tanto pode ocorrer pós uma queda, como também sem a pessoa reconhecer a existência de uma queda importante na sua vida. O objetivo geral do estudo foi o de estudar a relação medo e quedas. Utilizou-se como metodologia a aplicação de uma escala denominada FES-I Brasil que investiga a autoeficácia em executar determinadas tarefas, e de uma análise de conteúdo das entrevistas realizadas com as 15 participantes que se dispuseram a participar do estudo. No capítulo 1 discutimos a fundamentação que deu suporte a investigação, na sequência, no capítulo 2, apresentamos as opções metodológicas, descrevemos a forma como se estruturou a pesquisa e a coleta dos dados. No capítulo 3 apresentamos a análise dos dados coletados: encontramos uma medida central através da mediana, sem no entanto, sermos capazes de dizer se quem cai mais é quem tem mais medo; dito de outra forma, quem têm menor autoeficácia. No grupo investigado todos apresentaram quedas importantes e o medo das quedas em maior ou menor grau esteve presente no discurso das entrevistadas. A partir da análise do conteúdo das entrevistas pode-se conhecer melhor sobre as quedas do grupo. Categorias serviram para dialogar com as entrevistas e uma delas não prevista, veio a ser a da “fé como justificativa”, procurou minimizar o problema, desta forma, controlando a emoção expressa pelo sentir medo que acompanhou o grupo investigado. Apresentamos nas nossas considerações finais a relação das quedas que acontecem com os idosos e o sentimento de medo que as mesmas provocam entre as participantes da UBS-Vizella. / The aging population, has been influenced by the phenomenon of demographic transition and from the census data available since we found similar numbers to that of developed countries. With this raised concerns with comorbidities. Falls in elderly are regarded as one of the major problems of aging and to investigate the falls of the elderly was the purpose of this study investigating the elderly who attended the workshops proposed in the Vida Saudável Project which occurred in the Basic Health João da Silva Vizella. The literature indicates the decline as a predictor of fear that they cause, which may occur either after a fall, but no one recognized the existence of a significant drop in his life. The overall objective of the study was to study the relationship fear and falls. Was used as a methodology to apply a scale called FES-I Brazil that investigates the self-efficacy in performing certain tasks, and a content analysis of interviews with 15 participants who were willing to participate. In chapter 1 we discussed the rationale that has supported the research, following, in Chapter 2, we present the methodological options, we describe the way they structured the research and data collection. In chapter 3 we present the analysis of data collected: find a measure through the center median, without however being able to say whether those who fall is over who has more fear, in other words, who have lower self-efficacy. In the group investigated all showed significant falls and fear of falls in greater or lesser degree was present in the discourse of the interviewees. From the analysis of the interviews one can know better about the falls of the group. Categories used to dialogue with the interviews and one not envisaged, became the "faith as a justification," sought to minimize the problem, thereby controlling the emotion expressed by the fear that accompanied the group investigated. We present our final considerations in the relationship of falls that occur with the elderly and the feeling of fear that they cause among the participants of the UBS-Vizella.
|
68 |
Äldres upplevelse av dagliga aktiviteter efter fall : En kvalitativ intervjustudie / Older people' s experience of activities in daily life after fall. : A qualitative interview studyFlygare Pettersson, Julia, Jacklin, Isabelle January 2017 (has links)
Fallolyckor är vanligt förekommande bland äldre personer i Sverige. Trots detta saknas studier på de drabbades upplevelse efter ett fall. Syfte: Examensarbetets syfte var därför att beskriva hur äldre upplever sina dagliga aktiviteter efter fall. Metod: Metoden för examensarbetet var kvalitativ med semistrukturerade intervjuer. Nio personer i södra Sverige mellan 71–94 år har deltagit. Materialet har analyserats genom en kvalitativ innehållsanalys. Resultat: Resultatet mynnade ut i tre kategorier, känslor som påverkar utförandet av aktiviteter, fysiska upplevelser som leder till begränsningar samt strategier för att hantera vardagen. Efter fall upplevde många trötthet, rädsla och oro. Även smärta och försämrad rörelseförmåga förekom bland deltagarna. Konsekvenserna efter fall upplevdes påverka och begränsa vardagliga aktiviteter. Slutsats: I resultatet framkom att de personliga erfarenheterna, känslorna och upplevelsen av fall hade minst lika stor påverkan på vardagen som den tillhörande fysiska skadan. / Fall accidents are common among older people in Sweden. Despite that there is lack of studies about the affected person's experience after a fall. Purpose: The purpose of the study is therefore to describe how older people’s experience their daily activities after falling. Method: The study was a qualitative interview study with semi-structured interviews. Nine people 71-94 years old from south Sweden have been participating in the interview study. The collected data was analyzed with a qualitative content analysis. Result: The result was divided into three categories: Feelings that affect the performance of activities, physical experiences that lead to limitations and strategies for managing everyday life. Many experienced tiredness, fear and anxiety after a fall. Even pain and impaired mobility occurred among the participants. The consequences after a fall were found to affect and limit the everyday life. Conclusion: Based on the results of this study the personal experiences, feelings and the experience of the fall had at least as much influence on the daily life as the physical injury.
|
69 |
Impact Force Reduction Using Variable Stiffness with an Optimal Approach for Jumping RobotsCalderon Chavez, Juan Manuel 22 February 2017 (has links)
Running, jumping and walking are physical activities that are performed by humans in a simple and efficient way. However, these types of movements are difficult to perform by humanoid robots. Humans perform these activities without difficulty thanks to their ability to absorb the ground impact force. The absorption of the impact force is based on the human ability to vary muscles stiffness.
The principal objective of this dissertation is to study vertical jumps in order to reduce the impact force in the landing phase of the jump motion of humanoid robots. Additionally, the impact force reduction is applied to an arm-oriented movement with the objective of preserving the integrity of falling humanoid robot.
This dissertation focuses on researching vertical jump motions by designing, implementing and testing variable stiffness control strategies based on Computed-Torque Control while tracking desired trajectories calculated using the Zero Moment Point (ZMP) and the Center of Mass (CoM) conditions. Variable stiffness method is used to reduce the impact force during the landing phase. The variable stiffness approach was previously presented by Pratt et al. in [1], where they proposed that full stiffness is not always required. In this dissertation, the variable stiffness capability is implemented without the integration of any springs or dampers. All the actuators in the robot are DC Motors and the lower stiffness is achieved by the design and implementation of PID gain values in the PID controller for each motor. The current research proposes two different approaches to generate variable stiffness. The first approach is based on an optimal control theory where the linear quadratic regulator is used to calculate the gain values of the PID controller. The second approach is based on Fuzzy logic theory and it calculates the proportional gain (KP) of the PID controller. Both approaches are based on the idea of computing the PID gains to allow for the displacement of the DC motor positions with respect to the target positions during the landing phase. While a DC motor moves from the target position, the robot CoM changes towards a lower position reducing the impact force. The Fuzzy approach uses an estimation of the impact velocity and a specified desired soft landing level at the moment of impact in order to calculate the P gain of the PID controller. The optimal approach uses the mathematical model of the motor and the factor, which affects the Q matrix of the Linear Quadratic Regulator (LQR), in order to calculate the new PID values.
A One-legged robot is used to perform the jump motion verification in this research. In addition, repeatability experiments were also successfully performed with both the optimal control and the Fuzzy logic methods. The results are evaluated and compared according to the impact force reduction and the robot balance during the landing phase. The impact force calculation is based on the displacement of the CoM during the landing phase. The impact force reduction is accomplished by both methods; however, the robot balance shows a considerable improvement with the optimal control approach in comparison to the Fuzzy logic method. In addition, the Optimal Variable Stiffness method was successfully implemented and tested in Falling Robots. The robot integrity is accomplished by applying the Optimal Variable Stiffness control method to reduce the impact force on the arm joints, shoulders and elbows.
|
70 |
Peur de chuter, contrôle supraspinal de la marche et personne âgée : quelle relation ? / Fear of falling, supraspinal gait control and older people : is there an association?El Mir El Ayoubi, Farah 30 March 2015 (has links)
Les modifications de la marche liées à la peur de chuter sont généralement classées comme des troubles du contrôle de la marche supraspinaux, dits « de haut niveau » car rapportées à une déficience dans le contrôle cortical de la marche. Il est maintenant bien établi que l’étude de la variation des caractéristiques du pas, et notamment celles du temps du pas, est un moyen d’appréhender la désorganisation du caractère automatique de la marche. En effet, la variabilité du temps du cycle de marche qui semble être un marqueur du contrôle cortical de la marche est inversement reliée à la stabilité de la marche.Très peu d’études se sont intéressées à l’association entre la variabilité du temps du cycle de marche et la peur de chuter chez la personne âgée. Ces études ont montré des résultats divergents principalement en raison de la non-prise en compte de potentiels facteurs de confusion. Le travail de thèse que nous présentons a pour objectif principal d’étudier l’association entre la variabilité de la marche et la peur de chuter chez des personnes âgées en tenant compte des potentiels facteurs pouvant influencer la relation entre ces deux variables, afin d’appréhender la relation de causalité qui peut les unir. Nos résultats montrent que la peur de chuter est associée significativement à une augmentation de la variabilité de la marche. En effet, la combinaison peur de chuter et antécédent de chutes augmente la variabilité du temps du cycle de marche. Cependant, l’effet de cette combinaison dépend du niveau de la vitesse de la marche. / Changes in gait performance related to fear of falling (FOF) are usually classified as supraspinal gait control disorders called “higher-level gait disorders” due to impairment in cortical gait control. It is now well established that the study of the variability in stride characteristics and in particular the variability of stride time, provide information on the impairment of the automatic character of gait. In fact, gait variability, which is a biomarker of higher-level gait disorders, is inversely related to gait stability. A limited number of studies have examined the association between FOF and higher stride time variability (STV), and have showed mixed results mainly due to the non-consideration of potential factors that may influence the relationship between STV and FOF. Thus, the main objective of this thesis was to examine the association between STV and FOF in elder people taking into account the potential factors influencing the relationship between these two variables.Our results show that FOF is significantly associated with an increase in STV. Indeed, the combination of FOF and history of previous falls increases STV. The adverse gait effect of this combination depends on the level of the walking speed.
|
Page generated in 0.0748 seconds