Search results for "Microcontroller"
showing 10 items of 53 documents
Design and Low-Cost Implementation of an Optimally Robust Reduced-Order Rotor Flux Observer for Induction Motor Control
2007
The aim of this paper is to design and analyze reduced-order observers of the rotor flux of induction motors. The design is carried out in two steps. In the first step, a boundary of the stability region of the observation error is obtained corresponding to a chosen Lyapunov function. In the second step, the boundary is translated into a performance index that is minimized with respect to stator and rotor resistance variations and differences of voltages supplying the motor and those supplying the observer in order to obtain the largest stability region. Implementation of the observer on a low-cost fixed-point digital signal processor using look-up tables is described. Experimental results …
New ultraportable data logger to perform magnetic surveys
2019
This article presents the realization of a device for magnetic surveys It is a flexible, user-reprogramable, lightweight, and compact tool that can be easily integrated with aerial and marine drones. The device can accurately measure the local magnetic anomalies. It is based on the Atmega 2560 microcontroller and a digital 3-axis fluxgate magnetometer.
Design and realization of a portable multichannel continuous wave fNIRS
2014
A design and implementation of a portable functional Near InfraRed Spectroscopy embedded system prototype is described. In this theoretical and experimental work, we present an embedded system hosting 64 LED sources and 128 Silicon PhotoMultiplier detectors (SiPM). The elementary part of the structure is a flexible probe “leaf” consisting of 16 SiPMs, 4 couples of LEDs, each operating at two wavelengths, and a temperature sensor. The hardware system is based on an ARM main microcontroller that allows to perform both the switching time of LEDs and the acquisition of the SiPM outputs. The performed preliminary experimental tests achieved very promising results, thus demonstrating the effectiv…
PPG embedded system for blood pressure monitoring
2014
In this work, we have designed and implemented a microcontroller-based embedded system for blood pressure monitoring through a PhotoPlethysmoGraphic (PPG) technique. In our system, it is possible to perform PPG measurements via reflectance mode. Hardware novelty of our system consists in the adoption of Silicon PhotoMultiplier detectors. The signal received from the photodetector is used to calculate the instantaneous heart rate and therefore the heart rate variability. The obtained results show that, by using our system, it is possible to easily extract both the PPG and the breath signal. These signals can be used to monitor the patients during the convalescence both in hospital and at hom…
A new gas sensor electronic interface with generalized impedance converter
2008
A new gas sensor conditioning circuit that allows a direct resistance-to-frequency conversion, as well as the procedure for the design, is presented. The generalized impedance converter (GIC) proposed is configured as a variable capacitor connected with the capacitor timing terminal of an astable multivibrator implemented by a PSoC (programmable system on chip) microcontroller device. The GIC effective input impedance, which is controlled by the gas sensor resistance, controls the astable output frequency. Good correlation of the experimental output frequency, which depends on the gas concentration, is achieved. The circuit is a simple gas sensor digital interface with frequency output.
Study and design of a controlled oscillator for an embedded system to measure the complex impedance of PEM fuel cell »
2017
We present in this paper the study and the design of a voltage controlled oscillator (VCO) for an embedded system to diagnose the PEM fuel cell. Some problems related to fuel cells used in the electric vehicle field are the management of its efficiency and the lifetime of its membranes. To do this, the diagnosis using measuring the complex impedance is an important phase. It is based on the injection of a perturbation signal at the output of the PEM fuel cell, then we observe its behavior by measuring its impedance. The used measurement method is the electrochemical impedance spectroscopy (EIS) using the load modulation technique, which is implemented in an embedded measurement system based…
Real time estimation of photovoltaic modules characteristics and its application to maximum power point operation
2007
In this paper, an approximate curve fitting method for photovoltaic modules is presented. The operation is based on solving a simple solar cell electrical model by a microcontroller in real time. Only four voltage and current coordinates are needed to obtain the solar module parameters and set its operation at maximum power in any conditions of illumination and temperature. Despite its simplicity, this method is suitable for low cost real time applications, as control loop reference generator in photovoltaic maximum power point circuits. The theory that supports the estimator together with simulations and experimental results are presented.
Embedding Monitoring Systems for Cured-In-Place Pipes
2017
This paper proposes a non-intrusive electrical measurement system for monitoring some relevant parameters in pipeline systems. Temperature and flow-rate are monitored, using MEMS sensors. The flow-rate is evaluated by measuring pipe vibration, with a 3 axis accelerometer, induced by turbulence when fluid flows within the tube. The sensors are embedded, during the curing process of the cured-in-place pipes, in the pipes wall making the system suitable to be installed in renewed or new pipeline. The first experimental results show that it may be possible to obtain, at low-cost, a fully monitored distribution network.
Multithreaded Peripheral Processor for a Multicore Embedded System
2012
Multithreaded and multicore architectures represent a good solution used for increasing of parallelism degree exploited in modern computing systems and they can reduce the power dissipated in the chip by using low-frequency clock signals. These advantages recommend these parallel architectures for integration in the embedded systems, with restrictions imposed by the relatively small integration area. Particularities of embedded applications require hardware support able to handling in real time the peripheral interrupt requests. The performance of this hardware influences the performance of the entire parallel system. The current trend is to integrate in one microcontroller more processors …
Sensor-Oriented Passive RFID
2010
This chapter addresses the design of new UHF tag antennas for sensing applications able to host detectors and additional electronics but also to act as passive sensor itself for some modification of the target. Starting from the consideration that the tag is both a digital and an analog device, sensing data may be achieved without using microcontrollers by a simple signal processing of the tag response and of the turn-on power. The chapter is particularly focused on the monitoring of human body features even if the proposed ideas and devices, here demonstrated by simulations and experimentation, may also be applied in a variety of scenarios.