Sistema de control d'un MEMS ressonant per aplicacions espacials (CUBECAT)
Tutor / directorDomínguez Pumar, Manuel
Document typeMaster thesis, Master thesis (pre-Bologna period)
Rights accessOpen Access
The subject of labor of this project is based in PDO systems (Pulsed Digital Oscillator) for resonant MEMS with thermoelectric actuation. As its name indicates, they are a type of digital control oscillators, using a PLD, in which the MEMS actuation signal is formed by pulses. Its main characteristic is that, externally, its operation can be controlled so that the MEMS can oscillate in one of its different points of resonance. In addition, it captures and sends the digital value of this frequency to a PC. For the development of this project, we designed a new PDO model that fits to the maximum the definitive model intended for the CubeSat. The control, in this case, is made entirely from the PC, the same that receive the value of the oscillation frequency in digital measures. The aim of this project is to design a PDO control that allows making rounds of alternated measures for each of the modes for an undetermined period of time and save them in a text file with the corresponding time value. This approach and the PDO design conditions have forced the design of an auxiliary board needed to set communication with the PC as well as to the PLD can be programmed. The second purpose of this project has been the study of the behavior of the resonant frequency for the different MEMS modes depending on the pressure and to obtain their theoretical model. The realized work was to search a theoretical mode previously designed for MEMS with similar characteristics and to check that what this model says be what we obtain in the experimental measures. We have shown that the theoretical model characterize the behavior for the first two oscillation modes correctly. The last purpose has been to check the correspondence between the modes in which this PDO oscillates for different configurations and the modes in which it would have to oscillate according to the theory. Firstly, we have shown that using the no-fractional delays theory we do not achieve this correspondence. Then, we used the fractional delays theory to show the effect of the phase shift and the losses in the oscillation and anti-oscillation zones.
Treball acadèmic presentat a dues titulacions: Enginyeria Electrònica i Màster en Enginyeria Electrònica