A. Barriga

Implementation of CMOS fuzzy controllers as mixed-signal integrated circuits

This paper discusses architectural and circuit-level aspects related to hardware realizations of fuzzy controllers. A brief overview on fuzzy inference methods is given focusing on chip implementation. The singleton or zero-order Sugenos method is chosen since it offers a good tradeoff between hardware simplicity and control efficiency. The CMOS microcontroller described herein processes information in the current-domain, but input-output signals are represented as voltage to ease communications with conventional control circuitry. Programming functionalities are added by combining analog and digital techniques, giving rise to a versatile microcontroller, capable of solving different control problems. After identifying the basic component blocks, the circuits used for their implementation are discussed and compared with other alternatives. This study is illustrated with the experimental results of prototypes integrated in different CMOS technologies.

Design and application of digital fuzzy controllers

This paper focuses on hardware implementations of fuzzy inference systems which provide low silicon cost, high operational speed and adaptability to different application domains. The architecture and basic building blocks of two fuzzy logic controllers are described and their functionality is illustrated with experimental results showing the capability of these systems to be applied as function approximators.

Integrated circuit implementation of fuzzy controllers

This paper describes a system architecture for implementing fuzzy systems. Programming functionalities are added by combining analog and digital techniques, giving rise to a versatile microcontroller. Novel circuits to implement the required building blocks are provided and illustrated with experimental results.

Rapid design of fuzzy systems with Xfuzzy

The crecient use of fuzzy systems in complex applications has motivated us to develop a new version of Xfuzzy, the design environment for fuzzy system created at the IMSE (Instituto de Microelectronica de Sevilla). This new version, Xfuzzy 3.0, offers the advantages of being enterely programmed in Java, and allows designing hierarchical rule bases that can interchange fuzzy or non fuzzy values as well as employ user-defined fuzzy connectives, linguistic hedges, membership functions, and defuzzification methods. Xfuzzy 3.0 integrates tools that facilitate the description, tuning, verification, and synthesis of complex fuzzy systems. This is illustrated in this paper with the design of a fuzzy controller to solve a parking problem.

Hardware/software codesign of configurable fuzzy control systems

Abstract Fuzzy inference techniques are an attractive and well-established approach for solving control problems. This is mainly due to their inherent ability to obtain robust, low-cost controllers from the intuitive (and usually ambiguous or incomplete) linguistic rules used by human operators when describing the control process. This paper focuses on the hardware/software codesign of configurable fuzzy control systems. Two prototype systems implemented on general-purpose development boards are presented. In both of them, hardware components are based on specific and configurable fuzzy inference architecture whereas software tasks are supported by a microcontroller. The first prototype uses an off-the-shelf microcontroller and a low-complexity Xilinx XC4005XL field programmable gate array (FPGA). The second one is implemented as a system on programmable chip (SoPC), integrating the microcontroller together with the fuzzy hardware architecture and its interface circuits into a Xilinx Spartan2E200 FPGA.

Xfuzzy: a design environment for fuzzy systems

Xfuzzy is a CAD tool that eases the development of fuzzy systems from their conception to their final implementation. It is composed of a set of modules and programs that share a common specification language and cover the different stages of the design process. Modules for describing, verifying and tuning the behavior of the system are integrated within the environment. In addition to these features, common to other fuzzy design tools, a relevant characteristic of Xfuzzy is that it includes several synthesis facilities for implementing the system on either software or hardware.

XFVHDL: a tool for the synthesis of fuzzy logic controllers

A tool for the synthesis of fuzzy controllers is presented in this paper. This tool takes as input the behavioral specification of a controller and generates its VHDL description according to a target architecture. The VHDL code can be synthesized by means of two implementation methodologies, ASIC and FPGA. The main advantages of using this approach are rapid prototyping, and the use of well-known commercial design environments like Synopsys, Mentor Graphics, or Cadence.

Using Xfuzzy Environment for the Whole Design of Fuzzy Systems

Since 1992, Xfuzzy environment has been improving to ease the design of fuzzy systems. The current version, Xfuzzy 3, which is entirely programmed in Java, includes a wide set of new featured tools that allow automating the whole design process of a fuzzy logic based system: from its description (in the XFL3 language) to its synthesis in C, C++ or Java (to be included in software projects) or in VHDL (for hardware projects). The new features of the current version have been exploited in different application areas such as autonomous robot navigation and image processing.

SODS: a new CMOS differential-type structure

Differential-type structures to implement boolean functions find very interesting applications in self-timed circuits. A new structure of CMOS differential circuits is presented in this communication. This cell has been implemented on a standard 1.5 ¿m technology and has served to assess the structure and compare it with previously reported differential structures. Experimental laboratory results show improved timing and power performance, as well as gain in terms of transistor-count and area.

Accelerating Viola-Jones face detection for embedded and SoC environments

In this communication a speed optimized implementation of Viola-Jones Face Detection Algorithm based on the baseline OpenCV face detection application is presented. The baseline OpenCV face detection application is analyzed. Then the necessary modifications and improvements are described in order to accelerate the execution speed in an embedded or SoC (System-on-Chip) environments.