6 research outputs found
Embodied Models and Neurorobotics
Neuroscience has become a very broad field indeed: each year around 30,000
researchers and students from around the ... We trace a path from neuron to
cognition via computational neuroscience, but what is computational
neuroscience
The Runbot: engineering control applied to rehabilitation in spinal cord injury patients
Human walking is a complicated interaction among the musculoskeletal system, nervous
system and the environment. An injury affecting the neurological system, such as a spinal
cord injury (SCI) can cause sensor and motor deficits, and can result in a partial or complete
loss of their ambulatory functions. Functional electrical stimulation (FES), a technique to
generate artificial muscle contractions with the application of electrical current, has been
shown to improve the ambulatory ability of patients with an SCI. FES walking systems have
been used as a neural prosthesis to assist patients walking, but further work is needed to
establish a system with reduced engineering complexity which more closely resembles the
pattern of natural walking.
The aim of this thesis was to develop a new FES gait assistance system with a simple and
efficient FES control based on insights from robotic walking models, which can be used in
patients with neuromuscular dysfunction, for example in SCI.
The understanding of human walking is fundamental to develop suitable control strategies.
Limit cycle walkers are capable of walking with reduced mechanical complexity and simple
control. Walking robots based on this principle allow bio-inspired mechanisms to be analysed
and validated in a real environment. The Runbot is a bipedal walker which has been
developed based on models of reflexes in the human central nervous system, without the
need for a precise trajectory algorithm. Instead, the timing of the control pattern is based
on ground contact information. Taking the inspiration of bio-inspired robotic control, two
primary objectives were addressed. Firstly, the development of a new reflexive controller
with the addition of ankle control. Secondly, the development of a new FES walking system
with an FES control model derived from the principles of the robotic control system.
The control model of the original Runbot utilized a model of neuronal firing processes based
on the complexity of the central neural system. As a causal relationship between foot contact
information and muscle activity during human walking has been established, the control
model was simplified using filter functions that transfer the sensory inputs into motor outputs,
based on experimental observations in humans. The transfer functions were applied
to the RunBot II to generate a stable walking pattern. A control system for walking was
created, based on linear transfer functions and ground reaction information. The new control
system also includes ankle control, which has not been considered before. The controller
was validated in experiments with the new RunBot III.
The successful generation of stable walking with the implementation of the novel reflexive
robotic controller indicates that the control system has the potential to be used in controlling
the strategies in neural prosthesis for the retraining of an efficient and effective gait. To aid
of the development of the FES walking system, a reliable and practical gait phase detection
system was firstly developed to provide correct ground contact information and trigger timing
for the control. The reliability of the system was investigated in experiments with ten
able-bodied subjects. Secondly, an automatic FES walking system was implemented, which
can apply stimulation to eight muscles (four in each leg) in synchrony with the user’s walking
activity. The feasibility and effectiveness of this system for gait assistance was demonstrated
with an experiment in seven able-bodied participants.
This thesis addresses the feasibility and effectiveness of applying biomimetic robotic control
principles to FES control. The interaction among robotic control, biology and FES control
in assistive neural prosthesis provides a novel framework to developing an efficient and
effective control system that can be applied in various control applications
Biped locomotion control through a biologically-inspired closed-loop controller
Dissertação de mestrado integrado em Engenharia BiomédicaCurrently motor disability in industrialized countries due to neural and physical impairments
is an increasingly worrying phenomenon and the percentage of patients is expected
to be increasing continuously over the coming decades due to a process of ageing the world
is undergoing. Additionally, rising retirement ages, higher demand of elderly people for an
independent, dignified life and mobility, huge cost in the provision of health care are some
other determinants that motivate the restoration of motor function as one of the main goals of
rehabilitation. Modern concepts of motor learning favor a task-specific training in which all
movements in daily life should be trained/assisted repetitively in a physically correct fashion.
Considering the functional activity of the neuronal circuits within the spinal cord, namely
the central pattern generator (CPG), as the foundation to human locomotion, motor relearning
should be based on intensive training strategies directed to the stimulation and reorganization
of such neural pathways through mechanisms addressed by neural plasticity. To this
end, neuromodelings are required to simulate the human locomotion control to overcome the
current technological challenges such as developing smaller, intelligent and cost-effective
devices for home and work rehabilitation scenarios which can enable a continuous therapy/
assistance to guide the impaired limbs in a gentle manner, avoiding abrupt perturbations
and providing as little assistance as necessary. Biomimetic models, taking neurological and
biomechanical inspiration from biological animals, have been embracing these challenges
and developing effective solutions on refining the locomotion models in terms of energy
efficiency, simplicity in the structure and robust adaptability to environment changes and
unexpected perturbations.
Thus, the aim target of this work is to study the applicability of the CPG model for
gait rehabilitation, either for assistance and/or therapy purposes. Focus is developed on the
locomotion control to increase the knowledge of the underlying principles useful for gait
restoration, exploring the brainstem-spinal-biomechanics interaction more fully. This study
has great application in the project of autonomous robots and in the rehabilitation technology,
not only in the project of prostheses and orthoses, but also in the searching of procedures that
help to recuperate motor functions of human beings.
Encouraging results were obtained which pave the way towards the simulation of more
complex behaviors and principles of human locomotion, consequently contributing for improved
automated motor rehabilitation adapted to the rehabilitation emerging needs.Actualmente a debilidade motora em países industrializados devido a deficiências neurais
e físicas é um fenómeno crescente de apreensão sendo expectável um contínuo aumento do
rácio de pacientes nas próximas décadas devido ao processo de envelhecimento. Inclusivé,
o aumento da idade de reforma, a maior procura por parte dos idosos para uma mobilidade
e vida autónoma e condigna, o elevado custo nos cuidados de saúde são incentivos para a
restauração da função motora como um dos objectivos principais da reabilitação. Conceitos
recentes de aprendizagem motora apoiam um treino de tarefas específicas no qual movimentos
no quotidiano devem ser treinados/assistidos de forma repetitiva e fisicamente correcta.
Considerando a actividade funcional dos circuitos neurais na medula, nomeadamente
o gerador de padrão central (CPG), como a base da locomoção, a reaprendizagem motora
deve-se basear em estratégias intensivas de treino visando a estimulação e reorganização
desses vias neurais através de mecanismos abordados pela plasticidade neural. Assim,
são necessários modelos neurais para simular o controlo da locomoção humana de modo
a superar desafios tecnológicos actuais tais como o desenvolvimento de dispositivos mais
compactos, inteligentes e económicos para os cenários de reabilitação domiciliar e laboral
que podem permitir uma terapia/assistência contínua na guia dos membros debilitados de
uma forma suave, evitando perturbações abruptas e fornecendo assistência na medida do
necessário. Modelos biomiméticos, inspirando-se nos princípios neurológicos e biomecânicos
dos animais, têm vindo a abraçar esses desafios e a desenvolver soluções eficazes na
refinação de modelos de locomoção em termos da eficiência de energia, da simplicidade na
estrutura e da adaptibilidade robusta face a alterações ambientais e perturbações inesperadas.
Então, o objectivo principal do trabalho é estudar a aplicabilidade do modelo de CPG para
a reabilitação da marcha, para efeitos de assistência e/ou terapia. É desenvolvido um foco no
controlo da locomoção para maior entendimento dos princípios subjacentes úteis para a recuperação
da marcha, explorando a interacção tronco cerebral-espinal medula-biomecânica de
forma mais detalhada. Este estudo tem potencial aplicação no projecto de robôs autónomos
e na tecnologia de reabilitação, não só no desenvolvimento de ortóteses e próteses, mas também
na procura de procedimentos úteis para a recuperação da função motora.
Foram obtidos resultados promissores susceptíveis de abrir caminho à simulação de comportamentos
e princípios mais complexos da marcha, contribuindo consequentemente para
uma aprimorada reabilitação motora automatizada adaptada às necessidades emergentes
De animais a máquinas : humanos tecnicamente melhores nos imaginários de futuro da convergência tecnológica
Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Sociais, Departamento de Sociologia, 2020.O tema desta investigação é discutir os imaginários sociais de ciência e tecnologia que emergem
a partir da área da neuroengenharia, em sua relação com a Convergência Tecnológica de quatro
disciplinas: Nanotecnologia, Biotecnologia, tecnologias da Informação e tecnologias Cognitivas -
neurociências- (CT-NBIC). Estas áreas desenvolvem-se e são articuladas por meio de discursos
que ressaltam o aprimoramento das capacidades físicas e cognitivas dos seres humanos, com
o intuito de construir uma sociedade melhor por meio do progresso científico e tecnológico, nos
limites das agendas de pesquisa e desenvolvimento (P&D).
Objetivos:
Os objetivos nesse cenário, são discutir as implicações éticas, econômicas, políticas e sociais
deste modelo de sistema sociotécnico. Nos referimos, tanto as aplicações tecnológicas, quanto
as consequências das mesmas na formação dos imaginários sociais, que tipo de relações se
estabelecem e como são criadas dentro desse contexto.
Conclusão:
Concluímos na busca por refletir criticamente sobre as propostas de aprimoramento humano
mediado pela tecnologia, que surgem enquanto parte da agenda da Convergência Tecnológica
NBIC. No entanto, as propostas de melhoramento humano vão muito além de uma agenda de
investigação. Há todo um quadro de referências filosóficas e políticas que defendem o
aprimoramento da espécie, vertentes estas que se aliam a movimentos trans-humanistas e pós-
humanistas, posições que são ao mesmo tempo éticas, políticas e econômicas. A partir de nossa
análise, entendemos que ciência, tecnologia e política estão articuladas, em coprodução, em
relação às expectativas de futuros que são esperados ou desejados. Ainda assim, acreditamos
que há um espaço de diálogo possível, a partir do qual buscamos abrir propostas para o debate
público sobre questões de ciência e tecnologia relacionadas ao aprimoramento da espécie
humana.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)The subject of this research is to discuss the social imaginaries of science and technology that
emerge from the area of neuroengineering in relation with the Technological Convergence of four
disciplines: Nanotechnology, Biotechnology, Information technologies and Cognitive technologies
-neurosciences- (CT-NBIC). These areas are developed and articulated through discourses that
emphasize the enhancement of human physical and cognitive capacities, the intuition it is to build
a better society, through the scientific and technological progress, at the limits of the research
and development (R&D) agendas.
Objectives:
The objective in this scenery, is to discuss the ethic, economic, politic and social implications of
this model of sociotechnical system. We refer about the technological applications and the
consequences of them in the formation of social imaginaries as well as the kind of social relations
that are created and established in this context.
Conclusion:
We conclude looking for critical reflections about the proposals of human enhancement mediated
by the technology. That appear as a part of the NBIC technologies agenda. Even so, the
proposals of human enhancement go beyond boundaries that an investigation agenda. There is
a frame of philosophical and political references that defend the enhancement of the human
beings. These currents that ally to the transhumanism and posthumanism movements, positions
that are ethic, politic and economic at the same time. From our analysis, we understand that
science, technology and politics are articulated, are in co-production, regarding the expected and
desired futures. Even so, we believe that there is a space of possible dialog, from which we look
to open proposals for the public discussion on questions of science and technology related to
enhancement of human beings