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This paper has numerically analyzed the problem of enhanced the dynamic response of an electrohydrostatic actuators used in aerospace systems. Based on physical and mathematical model using both Matlab / Simulink and AMESim Software Student Edition some characteristics of this type of servo actuator were obtained. The results proved that a good tracking of reference is achieved and that the servo actuator meets very well the design requirements imposed in the time domain. [ABSTRACT FROM AUTHOR]

This paper presents a study concerning a canard UAV improvement using vectored thrust. There are taken into account the take-off and landing behavior. Vectored thrust can extent the attack angle range for a canard UAV, and so, one can decrease the take-off and landing speeds and also the take-off and landing distances. [ABSTRACT FROM AUTHOR]

In this paper is presented the simulation and analysis of a Fuzzy Energy Management for Hybrid Fuel cell/Battery Systems used for More Electric Aircraft. The fuel cell hybrid system contains of fuel cell, lithium-ion batteries along with associated dc to dc boost converters. In this configuration the battery has a dc to dc converter, because it is an active in the system. The energy management scheme includes the rule based fuzzy logic strategy. This scheme has a faster response to load change and is more robust to measurement imprecisions. Simulation will be provided using Matlab/Simulink based models. Simulation results are given to show the overall system performance. [ABSTRACT FROM AUTHOR]

In this paper one presents a model and an analysis of a dc-to-dc Buck converter, in closed loop, from 24V to 12 V with a power of 500 W. Model is implemented in MATLAB/SIMULINK toolbox SIMPOWERSYS. Control system is a fuzzy logic one, Mamdani type, and using P.I. configuration. One opted for a fuzzy controller due to its flexibility in its configuration and tuning process, and also because it doesn’t need to know a mathematical model for the Buck converter. Fuzzy controller is composed of two sub-controllers in parallel, one for the proportional component and a second for integrative component. One proposes this configuration because fewer inference rules are necessary and also the tuning process is easily accomplished compared to a fuzzy controller with two inputs. Implemented model is validated by numerical simulations and the results are realistic and confirm the possibility to use this type of controller. [ABSTRACT FROM AUTHOR]

The paper presents a way to obtain an intelligent miniaturized three-axial accelerometric sensor, based on the on-line estimation and compensation of the sensor errors generated by the environmental temperature variation. Taking into account that this error's value is a strongly nonlinear complex function of the values of environmental temperature and of the acceleration exciting the sensor, its correction may not be done off-line and it requires the presence of an additional temperature sensor. The proposed identification methodology for the error model is based on a neuro-fuzzy procedure which process off-line the numerical values obtained from the accelerometer experimental testing for different values of acceleration applied to its axes of sensitivity and for different values of operating temperature. In the sections of the paper are shown the results of the experimental testing of the accelerometer on all the three sensitivity axes, the identification of the error models on each axis by using fuzzy logic techniques combined with adaptive neural-network techniques, and the validation of the obtained models with experimental values. After the training of the neuro-fuzzy developed models for all of the three detection channels was obtained a reduction by almost two orders of magnitude of the acceleration absolute maximum error due to environmental temperature variation. [ABSTRACT FROM AUTHOR]

A way to improve the transient regime of a miniature accelerometer by using a smart control structure to close its loop is here presented. The control structure is developed by using the fuzzy logic techniques and it replaces an electronic block on the feedback path of the closed loop, block that, in the classical architecture, assured the system damping and, in the same time, played the role of elastic link of the accelerometer proof mass. The paper exposes gradually the operating principle of the miniature accelerometer, its mathematical modeling, the results obtained for classical closed loop architecture, the design procedure for the smart closed-loop control structure, and the results of the smart architecture. Finally, a comparative numerical study between the classical and the proposed accelerometer architectures is made [ABSTRACT FROM AUTHOR]