Javier Echanobe

Efficient Hardware/Software Implementation of an Adaptive Neuro-Fuzzy System

This paper describes the development of efficient hardware/software (HW/SW) neuro-fuzzy systems. The model used in this work consists of an adaptive neuro-fuzzy inference system modified for efficient HW/SW implementation. The design of two different on-chip approaches are presented: a high-performance parallel architecture for offline training and a pipelined architecture suitable for online parameter adaptation. Details of important aspects concerning the design of HW/SW solutions are given. The proposed architectures have been implemented using a system-on-a-programmable-chip. The device contains an embedded-processor core and a large field programmable gate array (FPGA). The processor provides flexibility and high precision to implement the learning algorithms, while the FPGA allows the development of high-speed inference architectures for real-time embedded applications.

Fuzzy systems, neural networks and neuro-fuzzy systems: A vision on their hardware implementation and platforms over two decades

Abstract In recent decades, and in order to develop applications covering several areas of knowledge, different researchers have been performing hardware implementations around paradigms such as fuzzy systems, neural networks or systems resulting from the hybridization of the previous two systems, known as neuro–fuzzy systems. Applications have been performed on different types of devices and/or platforms. The point of view of this paper is focused on a hardware taxonomy (devices where the applications have been implemented) and highlights the characteristics of the different applications covering the aforementioned paradigms done over the last two decades, and the beginning of the current decade. Special mention is made up of reconfigurable devices.

A System-on-Chip Development of a Neuro–Fuzzy Embedded Agent for Ambient-Intelligence Environments

This paper presents the development of a neuro-fuzzy agent for ambient-intelligence environments. The agent has been implemented as a system-on-chip (SoC) on a reconfigurable device, i.e., a field-programmable gate array. It is a hardware/software (HW/SW) architecture developed around a MicroBlaze processor (SW partition) and a set of parallel intellectual property cores for neuro-fuzzy modeling (HW partition). The SoC is an autonomous electronic device able to perform real-time control of the environment in a personalized and adaptive way, anticipating the desires and needs of its inhabitants. The scheme used to model the intelligent agent is a particular class of an adaptive neuro-fuzzy inference system with piecewise multilinear behavior. The main characteristics of our model are computational efficiency, scalability, and universal approximation capability. Several online experiments have been performed with data obtained in a real ubiquitous computing environment test bed. Results obtained show that the SoC is able to provide high-performance control and adaptation in a life-long mode while retaining the modeling capabilities of similar agent-based approaches implemented on larger computing machines.

Digital Hardware Implementation of High Dimensional Fuzzy Systems

This paper presents an algorithm to compute high dimensional piecewise linear (PWL) functions with simplicial division of the input domain, and introduces the circuit scheme for its implementation in a FPGA. It is also investigated how to modify this algorithm and implementation to compute a class of PWL fuzzy systems.

Deformed fuzzy automata for correcting imperfect strings of fuzzy symbols

Presents a fuzzy method for the recognition of strings of fuzzy symbols containing substitution, deletion, and insertion errors. As a preliminary step, we propose a fuzzy automaton to calculate a similarity value between strings. The adequate selection of fuzzy operations for computing the transitions of the fuzzy automaton allows us to obtain different string similarity definitions (including the Levenshtein distance). A deformed fuzzy automaton based on this fuzzy automaton is then introduced in order to handle strings of fuzzy symbols. The deformed fuzzy automaton enables the classification of such strings having an undetermined number of insertion, deletion and substitution errors. The selection of the parameters determining the deformed fuzzy automaton behavior would allow to implement recognizers adapted to different problems. The paper also presents algorithms that implement the deformed fuzzy automaton. Experimental results show good performance in correcting these kinds of errors.

A hardware/software embedded agent for real-time control of ambient-intelligence environments

This paper presents the development of an embedded intelligent agent able to perform real-time control of ambient-intelligence environments. The system has been implemented as a system-on-programmable chip (SoPC) on a field programmable gate array (FPGA). The scheme used for realizing the intelligent agent is an adaptive neuro-fuzzy system (NFS) enhanced with a principal component analysis (PCA) pre-processor. The PCA pre-processing stage allows a reduction of the input dimensions (features) with no meaningful loss of modeling capability. As a consequence, the computational complexity of the system is significantly reduced, allowing its implementation on a single electronic device. The NFS-PCA agent has been tested with data obtained in a real ubiquitous computing environment test bed. Results obtained show that the agent is able to perform real-time control of the environment in a proactive and non-intrusive way, and also to adapt to changes of users preferences in a life-long mode.

A real-time driver identification system based on artificial neural networks and cepstral analysis

The availability of advanced driver assistance systems (ADAS), for safety and well-being, is becoming increasingly important for avoiding traffic accidents caused by fatigue, stress, or distractions. For this reason, automatic identification of a driver from among a group of various drivers (i.e. real-time driver identification) is a key factor in the development of ADAS, mainly when the drivers comfort and security is also to be taken into account. The main focus of this work is the development of embedded electronic systems for in-vehicle deployment of driver identification models. We developed a hybrid model based on artificial neural networks (ANN), and cepstral feature extraction techniques, able to recognize the driving style of different drivers. Results obtained show that the system is able to perform real-time driver identification using non-intrusive driving behavior signals such as brake pedal signals and gas pedal signals. The identification of a driver from within groups with a reduced number of drivers yields promising identification rates (e.g. 3-driver group yield 84.6%). However, real-time development of ADAS requires very fast electronic systems. To this end, an FPGA-based hardware coprocessor for acceleration of the neural classifier has been developed. The coprocessor core is able to compute the whole ANN in less than 4 μs.

An FPGA-based multiprocessor-architecture for intelligent environments

Abstract In this paper we propose a SoPC-based multiprocessor embedded system for controlling ambiental parameters in an Intelligent Inhabited Environment. The intelligent features are achieved by means of a Neuro-Fuzzy system which has the ability to learn from samples, reason and adapt itself to changes in the environment or in user preferences. In particular, a modified version of the well known ANFIS (Adaptive Neuro-Fuzzy Inference System) scheme is used, which allows the development of very efficient implementations. The architecture proposed here is based on two soft-core microprocessors: one microprocessor is dedicated to the learning and adaptive procedures, whereas the other is dedicated to the on-line response. This second microprocessor is endowed with 4 efficient ad hoc hardware modules intended to accelerate the neuro-fuzzy algorithms. The implementation has been carried out on a Xilinx Virtex-5 FPGA and obtained results show that a very high performance system is achieved.

A neuro-genetic approach for modeling and optimizing a complex cogeneration process

Graphical abstractDisplay Omitted HighlightsA strategy for modeling and optimizing a cogeneration process of a industrial plant is presented.A multi-objective optimization approach is chosen.A computational study reveals that the ESPEA algorithm performs best.ESPEA approximates the Pareto front and puts an emphasis on regions that maximize efficiency. Cogeneration is the simultaneous generation of electricity and useful heat with the aim of exploiting more efficiently the energy stored in the fuel. Cogeneration is, however, a complex process that encompasses a great amount of sub-systems and variables. This fact makes it very difficult to obtain an analytical model of the whole plant, and therefore providing a mechanism or a methodology able to optimize the global behavior. This paper proposes a neuro-genetic strategy for modeling and optimizing a cogeneration process of a real industrial plant. Firstly, the modeling of the process is carried out by means of several interconnected neural networks where, each neural network deals with a particular sub-system of the plant. Next, the obtained models are used by a genetic algorithm, which solves a multiobjective optimization problem of the plant, where the goal is to minimize the fuel consumption and maximize both the generated electricity and the use of the heat. The proposed approach is evaluated with data of a real cogeneration plant collected over a one-year period. Obtained results show not only that the modeling of the plant is correct but also that the optimization increases significantly the efficiency of the cogeneration plant.

Driving Behavior Signals and Machine Learning: A Personalized Driver Assistance System

The progressive integration of driver assistance systems (DAS) into vehicles in recent decades has contributed to improving the quality of the driving experience. Currently, there is a need for individualization of advanced DAS with the aim of improving safety, security and comfort of the driver. In particular, the need to adapt the vehicle to individual preferences and requirements of the driver is an important research focus. In this work, an individualized and non-intrusive monitoring system for real-time driver support is proposed. The kernel of the system is a driver identification module based on driving behavior signals and a high-performance machine learning technique. The scheme is suitable for the development of single-chip embedded systems. Moreover, most of the measurement units used in this research are nowadays available in commercial vehicles, so the deployment of the system can be performed with minimal additional cost. Experimental results using a reduced set of features are very encouraging. Identification rates greater than 75% are obtained for a working set of 11 drivers, 86% for five-driver groups, 88% for four-driver groups, and 90% for three-driver groups.