Development of an active orthosis prototype for lower limbs

ARAUJO, Márcio V. ; ALSINA, Pablo J. ; MEDEIROS, Adelardo A. D. ; PEREIRA, Jonathan P.P. ; DOMINGOS, Elber C. ; ARAÚJO, Fábio M.U. ; SILVA, Jáder S. . Development of an Active Orthosis Prototype for Lower Limbs. In: INTERNATIONAL CONGRESS OF MECHANICAL ENGINEERING, 20., 2009, Gramado, RS. Proceedings… Gramado, RS: [s. n.], 2009

Desenvolvimento de Uma Órtese Ativa Para os Membros Inferiores Com Sistema Eletrônico Embarcado

This work presents the development of a prototype of an intelligent active orthosis for lower limbs whit an electronic embedded system. The proposed orthosis is an orthopedical device with the main objective of providing walking capacity to people with partial or total loss of lower limbs movements. In order to design the kinematics, dynamics and the mechanical characteristics of the prototype, the biomechanics of the human body was analized. The orthosis was projected to reproduce some of the movements of the human gait as walking in straight forward, sit down, get up, arise and go down steps. The joints of the orthosis are controlled by DC motors equipped with mechanical reductions, whose purpose is to reduce rotational speed and increase the torque, thus generating smooth movements. The electronic embedded system is composed of two motor controller boards with two channels that communicate with a embedded PC, position sensors and limit switches. The gait movements of the orthosis will be controlled by high level commands from a human-machine interface. The embedded electronic system interprets the high level commands, generates the angular references for the joints of the orthosis, controls and drives the actuators in order to execute the desired movements of the user

Avaliação da capacidade de caminhar do portador de obesidade mórbida utilizando teste de caminhada de 6 minutos

Introduction: The ability to walk is impaired in obese by anthropometric factors (BMI and height), musculoskeletal pain and level of inactivity. Little is known about the influence of body adiposity and the acute response of the cardiovascular system during whole the 6-minute walk test (6mWT). Objective: To evaluate the effect of anthropometric measures (BMI and WHR waist-to-hip ratio), the effort heart and inactivity in ability to walk the morbidly obese. Materials and Methods: a total 36 morbidly obese (36.23 + 11.82 years old, BMI 49.16 kg/m2) were recruited from outpatient department of treatment of obesity and bariatric surgery in University Hospital Onofre Lopes and anthropometric measurements of obesity (BMI and WHR), pulmonary function, pattern habitual physical activity (Baecke Questionnaire) and walking capacity (6mWT). The patient was checking to measure: heart rate (HR), breathing frequency (BF), peripheral oxygen saturation, level of perceived exertion, systemic arterial pressure and duplo-produto (DP), moreover the average speed development and total distance walking. The data were analysed between gender and pattern of body adiposity, measuring the behavior minute by minute of walking. The Pearson and Spearmam correlation coefficients were calculated, and stepwise multiple Regression examined the predictors of walking capacity. All analyses were performed en software Statistic 6.0. Results: 20 obese patients had abdominal adiposity (WHR = 1.01), waist circumference was 135.8 cm in women (25) and 139.8 cm in men (10). Walked to the end of 6mWT 412.43 m, with no differences between gender and adiposity. The total distance walked by obesity alone was explained by BMI (45%), HR in the sixth minute (43%), the Baecke (24%) and fatigue (-23%). 88.6% of obese (31) performed the test above 60% of maximal HR, while the peak HR achieved at 5-minute of 6mWT. Systemic arterial pressure and DP rised after walking, but with no differences between gender and adiposity. Conclusion: The walk of obese didn´t suffers influence of gender or the pattern of body adiposity. The final distance walked is attributed to excess body weight, stress heart, the feeling of effort required by physical activity and level of sedentary to obese. With a minute of walking, the obeses achieved a range of intensity cardiovascular trainning

Development of an active orthosis prototype for lower limbs

ARAUJO, Márcio V. ; ALSINA, Pablo J. ; MEDEIROS, Adelardo A. D. ; PEREIRA, Jonathan P.P. ; DOMINGOS, Elber C. ; ARAÚJO, Fábio M.U. ; SILVA, Jáder S. . Development of an Active Orthosis Prototype for Lower Limbs. In: INTERNATIONAL CONGRESS OF MECHANICAL ENGINEERING, 20., 2009, Gramado, RS. Proceedings… Gramado, RS: [s. n.], 2009