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This document proposes a new mathematical model of a solar cell that can be implemented in various software platforms. The model is based on an hyperbolic tangent function and linear equations for short circuit current, open circuit voltage and saturation conductance. It incorporates the irradiation and temperature effects and fits to the physical solar cell behavior by measuring the currents and...
This document exposes the architecture and performance of an improved Maximum Power Point Tracking (MPPT) circuit, applied to a high power solar cell. The circuit uses event-based control, such that the solar cell power oscillates between maximum value and a limit falling factor of its maximum. The circuit is composed in general by analog components as comparators, switches, attenuators and incorporates...
This paper presents the development of a collaborative event-based control applied to the problem of formation of a group of VTOL-UAVs (Vertical Take-off and Landing, Unmanned Aerial Vehicles). Each VTOL-UAV decides, based on the difference of its current state (linear position and velocity) and its latest broadcast state, when it has to send a new value to its neighbors. The asymptotic convergence...
This work presents an algorithm based on a non-linear observer to estimate the flexion and extension angle of the knee joint during the gait cycle. The proposed algorithm is evaluated in real-time using low-cost inertial sensors and a 32 bits Microcontroller.
This paper presents the development of a collaborative event-based control applied to the problem of consensus and formation of a group of VTOL-UAVs (Vertical Take-off and Landing, Unmanned Aerial Vehicles). Each VTOL-UAV decides, based on the difference of its current state (linear position and velocity) and its latest broadcast state, when it has to send a new value to its neighbors. The asymptotic...
In this paper the mathematical model of a fixed-wing UAV powered by solar energy is presented, the aim is to show the performance of a longitudinal control for this UAV, using successive loop closure. Also is presented a methodology for a photovoltaic (PV) array reconfiguration allowing the load to be matched and delivering the maximum power. The system model the longitudinal controller together with...
This paper presents the development of a quaternion-based nonlinear control for the attitude stabilization of VTOL-UAVs. Firstly, it is proved the existence of a Control Lyapunov Function (CLF). Unlike some previously proposed schemes, the aim of this paper is to propose an optimal control using the relationship between Sontag's Formula and optimal control problem. The control law ensures the asymptotic...
The next article describes the application of an alternative soft fault model strategy considering the cross-coupling effect analyse at the structural architecture for hydroelectric power system generator.The scheme is based on the Fuzzy Recursive Decision Feedback Extension (RDFE) tested and verify on a non-linear hydroelectric power system model obtained by a real system.The Timing, Sequencing and...
This paper discusses design constraints for low distortion Operational Transconductance Amplifiers (OTAs) on integrated analog front ends. It also compares traditional OTA topologies and proposes a new OTA showing significant reduction on distortion for wideband applications, the comparison is presented on a 0.35μm CMOS process. The proposed OTA is designed for on-chip analog front ends for radiation...
In this work, we investigate how WSN performs in the case when sink node moves using different radio models and metrics. We consider routing efficiency, delay and number of received packet metrics to evaluate the performance of WSN using AODV routing protocol, lattice topology, and TwoRayGround and Shadowing radio models. We evaluate the performance of WSN by simulations. The performance evaluation...
Call Admission Control (CAC) is one of the resource management functions, which regulates network access to ensure QoS provisioning. However, the decision for CAC is very challenging issue due to user mobility, limited radio spectrum, and multimedia traffic characteristics. We proposed a fuzzy-based CAC system by considering the priority of the on-going connections. We called this system FACS-P. In...
In this paper, we investigate how the sensor network performs in the case when the event moves with special movement path. We compare the simulation results for four scenarios: when the event is stationary, moving randomly, moving with simple 4 path and boids path. The simulation results have shown that for the case when event is moving randomly the performance is the worst in the four scenarios....
Vehicle Ad-hoc Network (VANET) is a kind of Mobile Ad-hoc Network (MANET) that establishes wireless connection between cars. In VANETs and MANETs, the topology of the network changes very often, therefore implementation of efficient routing protocols is very important problem. In MANETs, the Random Waypoint (RW) model is used as a simulation model for generating node mobility pattern. On the other...
For a long time, permanent magnet synchronous motors (PMSM) were only applied in some particular fields, e.g. for servo drives. However, in recent years PMSM gained increasing importance in novel domains like automotive hybrid drive trains. For Mexico, this boom represents a valuable opportunity for universities and research institutions, so that together with Mexican industry of the Electric Vehicle...
Wireless mobile networks and devices are becoming increasingly popular to provide users the access anytime and anywhere. The mobile systems are based on cellular approach and the area is covered by cells that overlap each other. Many handover algorithms are proposed in the literature. However, to make a better handover and keep the QoS in wireless networks is very difficult task. For this reason,...
The mobile cellular systems are expected to support multiple services with guaranteed quality of service (QoS).But, the ability of wireless systems to accommodate expected growth of traffic load and broadband services is limited by available radio frequency spectrum. Call admission control (CAC) is one of the resource management functions, which regulates network access to ensure QoS provisioning...
An induction motor drive, including a loss-model based efficiency controller, is presented in this paper. To improve the robustness of the control system, a self-tuning controller has been designed. Thermal effects and saturation are considered by an on-line rotor resistance estimator, and by the estimation of the mutual inductance respectively. Analysis, simulation, and experimental results are presented...
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