RESUMO
UNLABELLED: The recent engagement of Brazil in the construction and utilization of the International Space Station has motivated several Brazilian research institutions and universities to establish study centers related to Space Sciences. The Pontificia Universidade Catolica do Rio Grande do Sul (PUCRS) is no exception. METHOD: The University initiated in 1993 the first degree course training students to operate commercial aircraft in South America (the School of Aeronautical Sciences. A further step was the decision to build the first Brazilian laboratory dedicated to the conduct of experiments in ground-based microgravity simulation. Established in 1998, the Microgravity Laboratory, which was located in the Instituto de Pesquisas Cientificas e Tecnologicas (IPCT), was supported by the Schools of Medicine, Aeronautical Sciences and Electrical Engineering/Biomedical Engineering. At the end of 2006, the Microgravity Laboratory became a Center and was transferred to the School of Engineering. RESULTS: The principal activities of the Microgravity Centre are the development of research projects related to human physiology before, during and after ground-based microgravity simulation and parabolic flights, to aviation medicine in the 21st century and to aerospace biomedical engineering. CONCLUSION: The history of Brazilian, and why not say worldwide, space science should unquestionably go through PUCRS. As time passes, the pioneering spirit of our University in the aerospace area has become undeniable. This is due to the group of professionals, students, technicians and staff in general that have once worked or are still working in the Center of Microgravity, a group of faculty and students that excel in their undeniable technical-scientific qualifications.
RESUMO
This study aimed to develop a Walking Pattern Evaluation System during Hypogravity Simulation (SAMSH), which included the adaptation of a body suspension device, the instrumentation of a treadmill and the development of a virtual environment. SAMSH was developed using one subject. Kinematic analyses were performed whilst one individual was walking on the treadmill during body weight reduction simulating the gravitational forces of the Moon (reduction of 60%) and Mars (reduction of 30%) with and without virtual reality glasses (Head Mounted Display, HMD). The walking pattern was evaluated by means of knee and ankle electrogoniometers, foot switches placed on the front and back part of the plantar region, and five video cameras. Results showed that the body weight reduction during Moon simulation alter the walking pattern, including the increase in step time, contact time, step length and aerial time, and the decrease of walking cadence time (steps per minute). The findings of this study also suggested that hypogravity simulation reduces walking effort. The utilization of the HMD allowed the evaluation of the head position three-dimensionally during hypogravity simulation. The virtual environment reduced postural balance, due to the absence of visual input, which was evidenced by a protective extension reaction.
Assuntos
Engenharia/métodos , Marcha , Caminhada , Algoritmos , Fenômenos Biomecânicos , Peso Corporal , Simulação por Computador , Planeta Terra , Desenho de Equipamento , Humanos , Hipogravidade , Marte , Modelos Teóricos , Lua , Equilíbrio Postural , AstronaveRESUMO
A headward fluid shift occurs during microgravity exposure, which causes the cardiovascular adaptive syndrome. Different countermeasures have been proposed to decrease its symptomatology, like the application of lower body negative pressure (LBNP). A LBNP box with an environment control system was developed, aiming to improve features of LBNP boxes used worldwide. It consists of five carbon steel ribs in the shape of a cylinder, which is wrapped with high pressure resistant and transparent vinyl. Inner and outer-wheeled trolleys can comfortably and easily move the subject in and out of the box. A custom-made skirt is secured around the subject's waist by an adjustable belt. The other end is secured between two window-type wooden structures, which seal the LBNP box. Inlet and an outlet valves connect the external to the internal environment of the chamber and tube system allows air to circulate gently. Electronic sensors are used to adjust the airflow keeping a pre-set negative pressure without changing humidity and temperature inside the box. Structural, pressure profile and leaking tests were performed with successful results. The improvements of the present LBNP box have substantially decreased the undesirable side effects of uncontrolled environment conditions during rapid pressure changes, and increased test subjects' comfort.