670 research outputs found
Inter-spikes-intervals exponential and gamma distributions study of neuron firing rate for SVITE motor control model on FPGA
This paper presents a statistical study on a neuro-inspired spike-based implementation of the Vector-Integration-To-End-Point motor controller (SVITE) and compares its deterministic neuron-model stream of spikes with a proposed modification that converts the model, and thus the controller, in a Poisson like spike stream distribution. A set of hardware pseudo-random numbers generators, based on a Linear Feedback Shift Register (LFSR), have been introduced in the neuron-model so that they reach a closer biological neuron behavior. To validate the new neuron-model behavior a comparison between the Inter-Spikes-Interval empirical data and the Exponential and Gamma distributions has been carried out using the Kolmogorov–Smirnoff test. An in-hardware validation of the controller has been performed in a Spartan6 FPGA to drive directly with spikes DC motors from robotics to study the behavior and viability of the modified controller with random components.
The results show that the original deterministic spikes distribution of the controller blocks can be swapped with Poisson distributions using 30-bit LFSRs. The comparative between the usable controlling signals such as the trajectory and the speed profile using a deterministic and the new controller show a standard deviation of 11.53 spikes/s and 3.86 spikes/s respectively. These rates do not affect our system because, within Pulse Frequency Modulation, in order to drive the motors, time length can be fixed to spread the spikes. Tuning this value, the slow rates could be filtered by the motor. Therefore, this SVITE neuro-inspired controller can be integrated within complex neuromorphic architectures with Poisson-like neurons
Performance Study of Software AER-Based Convolutions on a Parallel Supercomputer
This paper is based on the simulation of a convolution model for bioinspired
neuromorphic systems using the Address-Event-Representation (AER)
philosophy and implemented in the supercomputer CRS of the University of
Cadiz (UCA). In this work we improve the runtime of the simulation, by
dividing an image into smaller parts before AER convolution and running each
operation in a node of the cluster. This research involves a test cases design in
which the optimal parameters are set to run the AER convolution in parallel
processors. These cases consist on running the convolution taking an image
divided in different number of parts, applying to each part a Sobel filter for
edge detection, and based on the AER-TOOL simulator. Execution times are
compared for all cases and the optimal configuration of the system is discussed.
In general, CRS obtain better performances when the image is divided than for
the whole image.Ministerio de Ciencia e Innovación TEC2009-10639-C04-0
NeuroPod: a real-time neuromorphic spiking CPG applied to robotics
Initially, robots were developed with the aim of making our life easier, carrying
out repetitive or dangerous tasks for humans. Although they were able
to perform these tasks, the latest generation of robots are being designed
to take a step further, by performing more complex tasks that have been
carried out by smart animals or humans up to date. To this end, inspiration
needs to be taken from biological examples. For instance, insects are able
to optimally solve complex environment navigation problems, and many researchers
have started to mimic how these insects behave. Recent interest in
neuromorphic engineering has motivated us to present a real-time, neuromorphic,
spike-based Central Pattern Generator of application in neurorobotics,
using an arthropod-like robot. A Spiking Neural Network was designed and
implemented on SpiNNaker. The network models a complex, online-change
capable Central Pattern Generator which generates three gaits for a hexapod
robot locomotion. Recon gurable hardware was used to manage both
the motors of the robot and the real-time communication interface with the
Spiking Neural Networks. Real-time measurements con rm the simulation
results, and locomotion tests show that NeuroPod can perform the gaits
without any balance loss or added delay.Ministerio de Economía y Competitividad TEC2016-77785-
Event-based control system on FPGA applied to the pencil balancer robotic platform
An event-based motor controller design is presented.
The system is designed to solve the classic inverted
pendulum problem by using a robotic platform and a totally
neuro-inspired event-based mechanism. Specifically, DVS retinas
provide feedback and an FPGA implements control. The robotic
platform used is the so called ’pencil balancer’. The retinas
provide visual information to the FPGA that processes it and
obtains the center of mass of the pencil. Once this center of
mass is averaged over time, it is used joint with the cart position
provided by a flat potentiometer bar to compute the angle of
the pencil from the vertical. The angle is delivered to an eventbased
Proportional-Derivative (PD) controller that drives the DC
motor using Pulse Frequency Modulation (PFM) to accomplish
the control objective. The results show an accurate, real-time and
efficient controller design
Visual Spike-based Convolution Processing with a Cellular Automata Architecture
this paper presents a first approach for
implementations which fuse the Address-Event-Representation
(AER) processing with the Cellular Automata using FPGA and
AER-tools. This new strategy applies spike-based convolution
filters inspired by Cellular Automata for AER vision
processing. Spike-based systems are neuro-inspired circuits
implementations traditionally used for sensory systems or
sensor signal processing. AER is a neuromorphic
communication protocol for transferring asynchronous events
between VLSI spike-based chips. These neuro-inspired
implementations allow developing complex, multilayer,
multichip neuromorphic systems and have been used to design
sensor chips, such as retinas and cochlea, processing chips, e.g.
filters, and learning chips. Furthermore, Cellular Automata is a
bio-inspired processing model for problem solving. This
approach divides the processing synchronous cells which
change their states at the same time in order to get the solution.Ministerio de Educación y Ciencia TEC2006-11730-C03-02Ministerio de Ciencia e Innovación TEC2009-10639-C04-02Junta de Andalucía P06-TIC-0141
Beneficial effects of dietary supplementation with green tea catechins and cocoa flavanols on aging-related regressive changes in the mouse neuromuscular system
This work was supported by Abbott and a grant from the Spanish Ministerio de Ciencia, Innovacion y Universidades cofinanced by Fondo Europeo de Desarrollo Regional (RTI2018-099278-B-I00 to JC and JE) .Besides skeletal muscle wasting, sarcopenia entails morphological and molecular changes in distinct components of the neuromuscular system, including spinal cord motoneurons (MNs) and neuromuscular junctions (NMJs); moreover, noticeable microgliosis has also been observed around aged MNs. Here we examined the impact of two flavonoid-enriched diets containing either green tea extract (GTE) catechins or cocoa flavanols on age-associated regressive changes in the neuromuscular system of C57BL/6J mice. Compared to control mice, GTE- and cocoa-supplementation significantly improved the survival rate of mice, reduced the proportion of fibers with lipofuscin aggregates and central nuclei, and increased the density of satellite cells in skeletal muscles. Additionally, both supplements significantly augmented the number of innervated NMJs and their degree of maturity compared to controls. GTE, but not cocoa, prominently increased the density of VAChT and VGluT2 afferent synapses on MNs, which were lost in control aged spinal cords; conversely, cocoa, but not GTE, significantly augmented the proportion of VGluT1 afferent synapses on aged MNs. Moreover, GTE, but not cocoa, reduced aging-associated microgliosis and increased the proportion of neuroprotective microglial phenotypes. Our data indicate that certain plant flavonoids may be beneficial in the nutritional management of age-related deterioration of the neuromuscular system.Abbott LaboratoriesSpanish Ministerio de Ciencia, Innovacion y UniversidadesEuropean Commission RTI2018-099278-B-I0
SVITE: A Spike-Based VITE Neuro-Inspired Robot Controller
This paper presents an implementation of a neuro-inspired algorithm
called VITE (Vector Integration To End Point) in FPGA in the spikes domain.
VITE aims to generate a non-planned trajectory for reaching tasks in robots.
The algorithm has been adapted to work completely in the spike domain under
Simulink simulations. The FPGA implementation consists in 4 VITE in parallel
for controlling a 4-degree-of-freedom stereo-vision robot. This work represents
the main layer of a complex spike-based architecture for robot neuro-inspired
reaching tasks in FPGAs. It has been implemented in two Xilinx FPGA
families: Virtex-5 and Spartan-6. Resources consumption comparative between
both devices is presented. Results obtained for Spartan device could allow
controlling complex robotic structures with up to 96 degrees of freedom per
FPGA, providing, in parallel, high speed connectivity with other neuromorphic
systems sending movement references. An exponential and gamma distribution
test over the inter spike interval has been performed to proof the approach to the
neural code proposed.Ministerio de Economía y Competitividad TEC2012-37868-C04-0
Live Demonstration: neuromorphic robotics, from audio to locomotion through spiking CPG on SpiNNaker.
This live demonstration presents an audio-guided
neuromorphic robot: from a Neuromorphic Auditory Sensor
(NAS) to locomotion using Spiking Central Pattern Generators
(sCPGs). Several gaits are generated by sCPGs implemented
on a SpiNNaker board. The output of these sCPGs is sent
in a real-time manner to an Field Programmable Gate Array
(FPGA) board using an AER-to-SpiNN interface. The control
of the hexapod robot joints is performed by the FPGA board.
The robot behavior can be changed in real-time by means of
the NAS. The audio information is sent to the SpiNNaker board
which classifies it using a Spiking Neural Network (SNN). Thus,
the input sound will activate a specific gait pattern which will
eventually modify the behavior of the robot.Ministerio de Economía y Competitividad TEC2016-77785-
Aplicación de MILP para flowshop sin permutación
En este trabajo fin de grado (TFG) se aborda la adaptación de una serie de modelos matemáticos a un entorno
productivo habitual. Se propone así un entorno de taller de flujo regular sin permutación, comparable a alguno
de los entornos reales encontrados en la industria de manufactura. La adaptación se lleva a cabo mediante el
desarrollo de los modelos de programación lineal entera mixta, llamados MILP, definiendo una función objetivo
con una serie de restricciones para cada modelo. Este procedimiento se hace mediante programación en lenguaje
C para automatizar los procesos y llamar al solver Gurobi para obtener los resultados. Por último, se estudiará
el rendimiento de los modelos con respecto a diferentes parámetros.Universidad de Sevilla. Grado en Ingeniería de las Tecnologías Industriale
On Real-Time AER 2-D Convolutions Hardware for Neuromorphic Spike-Based Cortical Processing
In this paper, a chip that performs real-time image
convolutions with programmable kernels of arbitrary shape is presented.
The chip is a first experimental prototype of reduced size
to validate the implemented circuits and system level techniques.
The convolution processing is based on the address–event-representation
(AER) technique, which is a spike-based biologically
inspired image and video representation technique that favors
communication bandwidth for pixels with more information. As
a first test prototype, a pixel array of 16x16 has been implemented
with programmable kernel size of up to 16x16. The
chip has been fabricated in a standard 0.35- m complimentary
metal–oxide–semiconductor (CMOS) process. The technique also
allows to process larger size images by assembling 2-D arrays of
such chips. Pixel operation exploits low-power mixed analog–digital
circuit techniques. Because of the low currents involved (down
to nanoamperes or even picoamperes), an important amount of
pixel area is devoted to mismatch calibration. The rest of the
chip uses digital circuit techniques, both synchronous and asynchronous.
The fabricated chip has been thoroughly tested, both at
the pixel level and at the system level. Specific computer interfaces
have been developed for generating AER streams from conventional
computers and feeding them as inputs to the convolution
chip, and for grabbing AER streams coming out of the convolution
chip and storing and analyzing them on computers. Extensive
experimental results are provided. At the end of this paper, we
provide discussions and results on scaling up the approach for
larger pixel arrays and multilayer cortical AER systems.Commission of the European Communities IST-2001-34124 (CAVIAR)Commission of the European Communities 216777 (NABAB)Ministerio de Educación y Ciencia TIC-2000-0406-P4Ministerio de Educación y Ciencia TIC-2003-08164-C03-01Ministerio de Educación y Ciencia TEC2006-11730-C03-01Junta de Andalucía TIC-141
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