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In this paper, we explore the capabilities of a sound classification system that combines both a novel FPGA cochlear model implementation and a bio-inspired technique based on a trained convolutional spiking network. The neuromorphic auditory system that is used in this work produces a form of representation that is analogous to the spike outputs of the biological cochlea. The auditory system has been developed using a set of spike-based processing building blocks in the frequency domain. They form a set of band pass filters in the spike-domain that splits the audio information in 128 frequency channels, 64 for each of two audio sources. Address Event Representation (AER) is used to communicate the auditory system with the convolutional spiking network. A layer of convolutional spiking network is developed and trained on a computer with the ability to detect two kinds of sound: artificial pure tones in the presence of white noise and electronic musical notes. After the training process, the presented system is able to distinguish the different sounds in real-time, even in the presence of white noise. Ministerio de Economía y Competitividad TEC2012-37868-C04-02

This paper presents a technique for synchronizing synchronous generators without speed control. The proposed construction is under development in a research project which aims to control auxiliary synchronous generators in a hydroelectric power unit. An UPFC device is used to achieve the synchronism of the synchronous generator with the power system. Simulation with different phases angles and voltage magnitude are presented to demonstrate the effectiveness and robustness of the proposed technique.

This paper presents an innovative proposal for a SCADA system platform, integrating oscillographic capabilities to the set of functions found in standard supervisory and control systems. The proposed SCADA system was developed using C++ language, targeted to x86-64/Windows 7 processing platforms, and is based on multithreading programming. The resulting system has a low implementation cost. The hardware architecture, along with the adopted software tools, satisfactorily meets all the requirements originally planned for the proposed system.

This paper presents the initial results of a research project that aims to develop a control system for active power regulation in synchronous auxiliary generators connected to hydraulic generation units. In this sense, the developed system is based on the compensation of the inductive impedance of the auxiliary generator using TCSC switched by IGBT0s. The control of IGBT0s firing angle is achieved by symmetric pulses generated by a PWM module. The proposed system was implemented and tested digitally in Simulink/MatLab environment considering several active power values demanded by an auxiliary distribution system of 400VCA. The promising results obtained in these simulations show the efficiency and robustness of the proposed methodology.

With the evolution observed nowadays in power electronics systems, frequency converters are increasingly used in the grid. However, due to switching techniques employed, the harmonic distortion of the resulting signals became an important parameter to be considered in the design of such converters. For this reason, special attention has been given to the techniques of pulse width modulation (PWM) aimed at reducing the harmonic content. This paper proposes a new methodology for the determination of the PWM pulses, based on the application of nonlinear numerical optimization technique using the Lagrange algorithm for minimizing an objective function. The application of this new technique enables the minimization of the total harmonic distortion (THD) at the same time that restrictions are imposed on the amplitudes of harmonic components of interest. Numerical results demonstrate the potentiality of the proposed methodology.

This paper presents initial project and test results of an active power control scheme development for auxiliary synchronous generators of an AES-Distribution System connected Hydraulic Generation Unit. An open loop control system using TCSC switched by IGBT's is proposed to compensate the inductive impedance of the synchronous generator and control the active power injection. Several switching angles were evaluated at different compensation levels and simulations are presented to analyze the effectiveness and robustness of the proposed controller project.

Neuromorphic engineers study models and implementations of systems that mimic neurons behavior in the brain. Neuro-inspired systems commonly use spikes to represent information. This representation has several advantages: its robustness to noise thanks to repetition, its continuous and analog information representation using digital pulses, its capacity of pre-processing during transmission time, ... , Furthermore, spikes is an efficient way, found by nature, to codify, transmit and process information. In this paper we propose, design, and analyze neuro-inspired building blocks that can perform spike-based analog filters used in signal processing. We present a VHDL implementation for FPGA. Presented building blocks take advantages of the spike rate coded representation to perform a massively parallel processing without complex hardware units, like floating point arithmetic units, or a large memory. Those low requirements of hardware allow the integration of a high number of blocks inside a FPGA, allowing to process fully in parallel several spikes coded signals. Junta de Andalucía P06-TIC-O1417 Ministerio de Ciencia e Innovación TEC2009-10639-C04-02 Ministerio de Ciencia e Innovación TEC2006-11730-C03-02

Correcting digital images tilt needs huge quantities of memory, high computational resources, and use to take a considerable amount of time. This demonstration shows how a spikes-based silicon retina dynamic vision sensor (DVS) tilt can corrected in real time using a commercial accelerometer. DVS output is a stream of spikes codified using the address-event representation (AER). Event-based processing is focused on change in real time DVS output addresses. Taking into account this DVS feature, we present an AER based layer able to correct in real time the DVS tilt, using a high speed algorithmic mapping layer and introducing a minimum latency in the system. A co-design platform (the AER-Robot platform), based into a Xilinx Spartan 3 FPGA and an 8051 USB microcontroller, has been used to implement the system.

Neuromorphic engineering tries to mimic biological information processing. Address-Event Representation (AER) is a neuromorphic communication protocol for spiking neurons between different chips. We present a new way to drive robotic platforms using spiking neurons. We have simulated spiking control models for DC motors, and developed a mobile robot (Eddie) controlled only by spikes. We apply AER to the robot control, monitoring and measuring the spike activity inside the robot. The mobile robot is controlled by the AER-Robot tool, and the AER information is sent to a PC using the USBAERmini2 interface. Junta de Andalucía P06-TIC-01417 Ministerio de Educación y Ciencia TEC2006-11730-C03-02

Address-event representation (AER) is a neuromorphic communication protocol for transferring information of spiking neurons implemented into VLSI chips. These neuro-inspired implementations have been used to design sensor chips (retina, cochleas), processing chips (convolutions, filters) and learning chips, what makes possible the development of complex, multilayer, multichip neuromorphic systems. In biology one of the last steps of the processing is to move a muscle, to apply the results of these complex neuromorphic processing to the real world. One interesting question is to be able to transform, or translate, the AER information into robot movements, like for example, moving a DC motor. This paper presents several ways to translate AER spikes into DC motor power, and to control a DC motor speed, based on Pulse Frequency Modulation. These methods have been simulated into Simulink with Xilinx system generator, and tested into the AER-Robot platform.

Address-event-representation (AER) is an asynchronous protocol for transferring the information of spiking neuro-inspired systems. Actually AER systems are able to see, to ear, to process information, and to learn. Regarding to the actuation step, the AER has been used for implementing central pattern generator algorithms, but not for controlling the actuators in a closed-loop spike-based way. In this paper we analyze an AER based model for a real-time neuro-inspired closed-loop control system. We demonstrate it into a differential control system for a two-wheel vehicle using feedback AER information. PFM modulation has been used to power the DC motors of the vehicle and translation into AER of encoder information is also presented for the close-loop. A codesign platform (called AER-Robot), based into a Xilinx Spartan 3 FPGA and an 8051 USB microcontroller, with power stages for four DC motors has been used for the demonstrator.

Address-Event-Representation (AER) is a communication protocol for transferring asynchronous events between VLSI chips, originally developed for bio-inspired processing systems (for example, image processing). Such systems may consist of a complicated hierarchical structure with many chips that transmit data among them in real time, while performing some processing (for example, convolutions). The event information is transferred using a high speed digital parallel bus (typically 16 bits and 20ns-40ns per event). This paper presents a testing platform for AER systems that allows analysing a LVDS Serial AER link produced by a Spartan 3 FPGA, or by a commercial LVDS transceiver. The interface allows up to 0.728 Gbps (~40Mev/s, 16 bits/ev). The eye diagram ensures that the platform could support 1.2 Gbps. Commission of the European Communities IST-2001-34124 (CAVIAR) Comisión Interministerial de Ciencia y Tecnología TIC-2003-08164-C03-02

Address-event-representation (AER) is a communication protocol for transferring asynchronous events between VLSI chips, originally developed for bio-inspired processing systems (for example, image processing). Such systems may consist of a complicated hierarchical structure with many chips that transmit data among them in real time, while performing some processing (for example, convolutions). The event information is transferred using a high speed digital parallel bus (typically 16 bits and 20ns-40ns per event). This paper presents a testing platform for AER systems that allows to analyse a LVDS Serial AER link. The interface allows up to 0.7 Gbps (~40Mev/s, 16 bits/ev). The eye diagram ensures that the platform could support 1.2 Gbps.

A high speed sample image processing application using AER-based components is presented. The setup objective is to distinguish between two propellers of different shape rotating at high speed (around 1000 revolutions/sec) to show event-based systems capabilities in high speed applications. Event-based schemes allow the most relevant information to propagate faster through the system layers. So image processing is sped up because a rough result may be available when only a little part of the input has arrived. This setup is much faster than the conventional frame-based image processing systems because they would need to process more than 10kFrames/s to do the same task proposed here, whereas only few events are required with the event based technique.

Address-Event-Representation (AER) is a communications protocol for transferring images between chips, originally developed for bio-inspired image processing systems. Such systems may consist of a complicated hierarchical structure with many chips that transmit images among them in real time, while performing some processing (for example, convolutions). In developing AER based systems it is very convenient to have available some kind of means of generating AER streams from on-computer stored images. In this paper we present a method for generating AER streams in real time from images stored in a computer’s memory. The method exploits the concept of linear feedback shift register random number generators. This method has been tested by software and compared to other possible algorithms for generating AER streams. It has been found that the proposed method yields a minimum error with respect to the ideal situation. A hardware platform that exploits this technique is currently under development.

The architecture of a modular VLSI signal processor with highly reconfigurable architecture is discussed. The processor has three types of modules: function modules; interconnection modules; and signal generation/nonlinear function generation modules. Signals are represented as currents. Multiplying transconductance amplifiers are used to implement linear and nonlinear programmable building blocks. >

This paper presents a method for designing fuzzy logic controllers by using the experience of human operators and/or control engineers. This five-step method, involving a fuzzy logic controller, uses a modified fuzzy associative memory (FAM) approach. The Magnetic Ball Suspension Problem (a nonlinear system problem) is used for illustrative purposes. Comparisons with an optimal PD controller in the linearized and nonlinear cases are made with the result that not only is the fuzzy logic controller more robust than the optimal PD controller in the sense of stability, but it also provides better performance for a given performance index. >

The authors present data demonstrating early cardiovascular responses to simulated gravity levels between 1G and -1G. A noninvasive, cardiac impedance cardiography system (the IQ System) was used to evaluate cardiac output (CO), stroke volume (SV), ventricular ejection time (VET), ejection fraction (EF), and pre-ejection period (PEP). Seven subjects were positioned at selected angles of +90/spl deg/, +45/spl deg/, 0/spl deg/, -45/spl deg/, and -90/spl deg/ for five minutes at each angle. These postural changes simulate different gravitational forces on the human body ranging from +1G to -1G. This study's findings demonstrate an overall increasing trend in CO, SV, VET and EF, and a slight decrease in PEP with postural changes from +90/spl deg/ to -90/spl deg/. Findings may aid responses to low and negative gravity environments. >