Desenvolvimento de uma plataforma vibratória associada a um volante de inércia

Abstract

There has been a recent increase in the use of new technologies playing an important role in promoting physical fitness, due to the positive impact they have on the health and quality of life of the individual. Taking this into consideration, the present work describes the development of a vibration platform linked to a flywheel (PV²I), which permits whole-body vibration (WBV) and resistance or isoinertial training. Correct measurement of the force values given by the flywheel and amplitude, frequency and acceleration ranges provided by the vibration platform was necessary for production of the prototype. The need to adapt various pieces of equipment and materials was also identified, such as the vibrator motor, springs, vibration dampers, roller bearings, axis, flywheel and frequency inverter. The equipment was validated through laboratory testing, aimed at verifying the performance of the PV²I. A comparator clock was used to measure amplitude, and a triaxial accelerometer provided the platform acceleration data. A frequency inverter was used to regulate the platform frequency. The vibration platform frequencies chosen for the prototype operation evaluation tests were 5Hz to 60Hz, with no platform load, the vibrator motor set at minimum intensity, with acceleration on all three axes (x, y and z) and amplitude measured every 5Hz. Tests were subsequently performed with a 52kg load, simulating the weight of a person, and the vibrator motor set at a vibration intensity of 10% and 20%. Both the platform displacement amplitude and acceleration measurements were acquired at 15Hz, 20Hz, 25Hz, 30Hz and 35Hz, and acceleration alone was also recorded at 40 Hz and 45 Hz. Two further tests were performed with a 55kg load and vibrator motor set at 30% and 40% intensity. These choices were based on findings in the literature, where the most encountered frequency ranges varied between 15Hz and 44Hz. The results demonstrate a relationship between frequency and amplitude; when one is altered the other also changes. The acceleration values collected during testing were used to analyze the vibration levels, in accordance with the ISO 2631-1 (1997) standard. The vibration levels of the platform, in the test configurations used, were confirmed as being acceptable.