785 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
Synthetic Generation of Events for Address-Event-Representation Communications
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
Improved Contrast Sensitivity DVS and its Application to Event-Driven Stereo Vision
This paper presents a new DVS sensor with
one order of magnitude improved contrast sensitivity over
previous reported DVSs. This sensor has been applied to a
bio-inspired event-based binocular system that performs
3D event-driven reconstruction of a scene. Events from two
DVS sensors are matched by using precise timing
information of their ocurrence. To improve matching
reliability, satisfaction of epipolar geometry constraint is
required, and simultaneously available information on the
orientation is used as an additional matching constraint.Ministerio de Economía y Competitividad PRI-PIMCHI-2011-0768Ministerio de Economía y Competitividad TEC2009-10639-C04-01Junta de Andalucía TIC-609
Live Demonstration: Retinal ganglion cell software and FPGA implementation for object detection and tracking
This demonstration shows how object detection and
tracking are possible thanks to a new implementation which
takes inspiration from the visual processing of a particular type
of ganglion cell in the retina
An Event-Driven Multi-Kernel Convolution Processor Module for Event-Driven Vision Sensors
Event-Driven vision sensing is a new way of sensing
visual reality in a frame-free manner. This is, the vision sensor
(camera) is not capturing a sequence of still frames, as in conventional
video and computer vision systems. In Event-Driven sensors
each pixel autonomously and asynchronously decides when to
send its address out. This way, the sensor output is a continuous
stream of address events representing reality dynamically continuously
and without constraining to frames. In this paper we present
an Event-Driven Convolution Module for computing 2D convolutions
on such event streams. The Convolution Module has been
designed to assemble many of them for building modular and hierarchical
Convolutional Neural Networks for robust shape and
pose invariant object recognition. The Convolution Module has
multi-kernel capability. This is, it will select the convolution kernel
depending on the origin of the event. A proof-of-concept test prototype
has been fabricated in a 0.35 m CMOS process and extensive
experimental results are provided. The Convolution Processor has
also been combined with an Event-Driven Dynamic Vision Sensor
(DVS) for high-speed recognition examples. The chip can discriminate
propellers rotating at 2 k revolutions per second, detect symbols
on a 52 card deck when browsing all cards in 410 ms, or detect
and follow the center of a phosphor oscilloscope trace rotating at
5 KHz.Unión Europea 216777 (NABAB)Ministerio de Ciencia e Innovación TEC2009-10639-C04-0
Embedding Multi-Task Address-Event- Representation Computation
Address-Event-Representation, AER, is a communication protocol that is
intended to transfer neuronal spikes between bioinspired chips. There are
several AER tools to help to develop and test AER based systems, which may
consist of a hierarchical structure with several chips that transmit spikes
among them in real-time, while performing some processing. Although these
tools reach very high bandwidth at the AER communication level, they require
the use of a personal computer to allow the higher level processing of the
event information. We propose the use of an embedded platform based on a
multi-task operating system to allow both, the AER communication and
processing without the requirement of either a laptop or a computer. In this
paper, we present and study the performance of an embedded multi-task AER
tool, connecting and programming it for processing Address-Event
information from a spiking generator.Ministerio de Ciencia e Innovación TEC2006-11730-C03-0
An AER handshake-less modular infrastructure PCB with x8 2.5Gbps LVDS serial links
Nowadays spike-based brain processing emulation is
taking off. Several EU and others worldwide projects are
demonstrating this, like SpiNNaker, BrainScaleS, FACETS, or
NeuroGrid. The larger the brain process emulation on silicon is,
the higher the communication performance of the hosting
platforms has to be. Many times the bottleneck of these system
implementations is not on the performance inside a chip or a
board, but in the communication between boards. This paper
describes a novel modular Address-Event-Representation (AER)
FPGA-based (Spartan6) infrastructure PCB (the AER-Node
board) with 2.5Gbps LVDS high speed serial links over SATA
cables that offers a peak performance of 32-bit 62.5Meps (Mega
events per second) on board-to-board communications. The
board allows back compatibility with parallel AER devices
supporting up to x2 28-bit parallel data with asynchronous
handshake. These boards also allow modular expansion
functionality through several daughter boards. The paper is
focused on describing in detail the LVDS serial interface and
presenting its performance.Ministerio de Ciencia e Innovación TEC2009-10639-C04-02/01Ministerio de Economía y Competitividad TEC2012-37868-C04-02/01Junta de Andalucía TIC-6091Ministerio de Economía y Competitividad PRI-PIMCHI-2011-076
Efficient DMA transfers management on embedded Linux PSoC for Deep-Learning gestures recognition: Using Dynamic Vision Sensor and NullHop one-layer CNN accelerator to play RoShamBo
This demonstration shows a Dynamic Vision Sensor able
to capture visual motion at a speed equivalent to a highspeed
camera (20k fps). The collected visual information is presented as
normalized histogram to a CNN accelerator hardware, called
NullHop, that is able to process a pre-trained CNN to
play Roshambo against a human. The CNN designed for this
purpose consist of 5 convolutional layers and a fully connected
layer. The
latency for processing one histogram is 8ms. NullHop is deployed
on the FPGA fabric of a PSoC from Xilinx, the Zynq 7100, which
is based on a dual-core ARM computer and a Kintex-7 with 444K
logic cells, integrated in the same chip. ARM computer is running
Linux and a specific C++ controller is running the whole
demo. This controller runs at user space in order to extract the
maximum throughput thanks to an efficient use of the AXIStream,
based of
DMA transfers. This short delay needed to process one
visual histogram, allows us to average several consecutive
classification
outputs. Therefore, it provides the best estimation of the symbol
that the user presents to the visual sensor. This output is then
mapped to present the winner symbol within the 60ms latency
that the brain considers acceptable before thinking that there is a
trick.Ministerio de Economía y Competitividad TEC2016-77785-
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-
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