Validação experimental de um modelo matemático representativo de um sistema pneumático de posicionamento

Abstract

Pneumatic positioning systems are relatively light, clean and of low cost presenting a good relationship between weight and power. These features make this kind of system a good choice of actuating for most applications. It appears, however, that these systems present some disadvantages among which stand out their nonlinearities imposed mainly by the compressibility of air, by the leaks of the system, by the friction and by the dead zone and that hinder its modeling, these being, target of study of several authors. In this context, it is observed that there is a point less explored then other ones, related to the mathematical modeling of the dynamics of the adopted control valve. Several authors neglect the dynamic behavior of these valves by considering it is very high compared to the rest of the system dynamic. Related to this claim, it is intended, in this paper, continue a specific modeling process, representative of the dynamic behavior of a pneumatic positioning system including the dynamic behavior of a proportional directional control valve, aiming check its validity. The results for the validation of the model are obtained by computer simulation, which are then compared to experimental results and to data of the adopted components, extracted from the datasheets of the manufacturers.