Numerical analysis of the modal coupling at low resonances in a Colombian Andean Bandola in C using the finite element method

The work presented in this thesis is concerned with the dynamical behavior of a CBandola's acoustical box at low resonances -- Two models consisting of two and three coupled oscillators are proposed in order to analyse the response at the first two and three resonances, respectively -- These models describe the first resonances in a bandola as a combination of the lowest modes of vibration of enclosed air, top and back plates -- Physically, the coupling between these elements is caused by the fluid-structure interaction that gives rise to coupled modes of vibration for the assembled resonance box -- In this sense, the coupling in the models is expressed in terms of the ratio of effective areas and masses of the elements which is an useful parameter to control the coupling -- Numerical models are developed for the analysis of modal coupling which is performed using the Finite Element Method -- First, it is analysed the modal behavior of separate elements: enclosed air, top plate and back plate -- This step is important to identify participating modes in the coupling -- Then, a numerical model of the resonance box is used to compute the coupled modes -- The computation of normal modes of vibration was executed in the frequency range of 0-800Hz -- Although the introduced models of coupled oscillators only predict maximum the first three resonances, they also allow to study qualitatively the coupling between the rest of the computed modes in the range -- Considering that dynamic response of a structure can be described in terms of the modal parameters, this work represents, in a good approach, the basic behavior of a CBandola, although experimental measurements are suggested as further work to verify the obtained results and get more information about some characteristics of the coupled modes, for instance, the phase of vibration of the air mode and the radiation e ciency

Medisuite + Iplate Integration EAFIT & Ilimitada S.A.

Force plate or pressure plate analysis came as an innovative tool to biomechanics and sport medicine -- This allows engineers, scientists and doctors to virtually reconstruct the way a person steps while running or walking using a measuring system and a computer -- With this information they can calculate and analyze a whole set of variables and factors that characterize the step -- Then they are able to make corrections and/or optimizations, designing appropriate shoes and insoles for the patient -- The idea is to study and understand all the hardware and software implications of this process and all the components involved, and then propose an alternative solution -- This solution should have at least similar performance to existing systems -- It should increase the accuracy and/or the sampling frequency to obtain better results -- By the end, there should be a working prototype of a pressure measuring system and a mathematical model to govern it -- The costs of the system have to be lower than most of the systems in the market