8 research outputs found
Towards an intelligent and supportive environment for people with physical or cognitive restrictions
AmbienNet environment has been developed with the aim
of demonstrating the feasibility of accessible
intelligent environments designed to support people with
disabilities and older persons living independently. Its main
purpose is to examine in depth the advantages and disadvantages
of pervasive supporting systems based on the paradigm of
Ambient Intelligence for people with sensory, physical or
cognitive limitations. Hence diverse supporting technologies
and applications have been designed in order to test their
accessibility, ease of use and validity. This paper presents
the architecture of AmbienNet intelligent environment and
an intelligent application to support indoors navigation for
smart wheelchairs designed for validation purposes.Ministerio de Educación y Ciencia TIN2006-15617-C[01,02,03
Adapted control methods for cerebral palsy users of an intelligent wheelchair
The development of an intelligent wheelchair (IW) platform that may be easily adapted to any commercial electric powered wheelchair and aid any person with special mobility needs is the main objective of this project. To be able to achieve this main objective, three distinct control methods were implemented in the IW: manual, shared and automatic. Several algorithms were developed for each of these control methods. This paper presents three of the most significant of those algorithms with emphasis on the shared control method. Experiments were performed by users suffering from cerebral palsy, using a realistic simulator, in order to validate the approach. The experiments revealed the importance of using shared (aided) controls for users with severe disabilities. The patients still felt having complete control over the wheelchair movement when using a shared control at a 50% level and thus this control type was very well accepted. Thus it may be used in intelligent wheelchairs since it is able to correct the direction in case of involuntary movements of the user but still gives him a sense of complete control over the IW movement
Shared Control for Wheelchair Interfaces
Independent mobility is fundamental to the quality of life of people with impairment. Most people with severe mobility impairments, whether congenital, e.g., from cerebral palsy, or acquired, e.g., from spinal cord injury, are prescribed a wheelchair. A small yet significant number of people are unable to use a typical powered wheelchair controlled with a joystick. Instead, some of these people require alternative interfaces such as a head- array or Sip/Puff switch to drive their powered wheelchairs. However, these alternative interfaces do not work for everyone and often cause frustration, fatigue and collisions. This thesis develops a novel technique to help improve the usability of some of these alternative interfaces, in particular, the head-array and Sip/Puff switch. Control is shared between a powered wheelchair user, using an alternative interface and a pow- ered wheelchair fitted with sensors. This shared control then produces a resulting motion that is close to what the user desires to do but a motion that is also safe. A path planning algorithm on the wheelchair is implemented using techniques in mo- bile robotics. Afterwards, the output of the path planning algorithm and the user’s com- mand are both modelled as random variables. These random variables are then blended in a joint probability distribution where the final velocity to the wheelchair is the one that maximises the joint probability distribution. The performance of the probabilistic approach to blending the user’s inputs with the output of a path planner, is benchmarked against the most common form of shared control called linear blending. The benchmarking consists of several experiments with end users both in a simulated world and in the real-world. The thesis concludes that probabilistic shared control provides safer motion compared with the traditional shared control for difficult tasks and hard-to-use interfaces
Mobile Robots
The objective of this book is to cover advances of mobile robotics and related technologies applied for multi robot systems' design and development. Design of control system is a complex issue, requiring the application of information technologies to link the robots into a single network. Human robot interface becomes a demanding task, especially when we try to use sophisticated methods for brain signal processing. Generated electrophysiological signals can be used to command different devices, such as cars, wheelchair or even video games. A number of developments in navigation and path planning, including parallel programming, can be observed. Cooperative path planning, formation control of multi robotic agents, communication and distance measurement between agents are shown. Training of the mobile robot operators is very difficult task also because of several factors related to different task execution. The presented improvement is related to environment model generation based on autonomous mobile robot observations
Classificação de pacientes para adaptação de cadeira de rodas inteligente
Doutoramento em Engenharia InformáticaA importância e preocupação dedicadas à autonomia e independência das
pessoas idosas e dos pacientes que sofrem de algum tipo de deficiência tem
vindo a aumentar significativamente ao longo das últimas décadas. As
cadeiras de rodas inteligentes (CRI) são tecnologias que podem ajudar este
tipo de população a aumentar a sua autonomia, sendo atualmente uma área
de investigação bastante ativa. Contudo, a adaptação das CRIs a pacientes
específicos e a realização de experiências com utilizadores reais são assuntos
de estudo ainda muito pouco aprofundados.
A cadeira de rodas inteligente, desenvolvida no âmbito do Projeto IntellWheels,
é controlada a alto nível utilizando uma interface multimodal flexível,
recorrendo a comandos de voz, expressões faciais, movimentos de cabeça e
através de joystick. Este trabalho teve como finalidade a adaptação automática
da CRI atendendo às características dos potenciais utilizadores.
Foi desenvolvida uma metodologia capaz de criar um modelo do utilizador. A
investigação foi baseada num sistema de recolha de dados que permite obter
e armazenar dados de voz, expressões faciais, movimentos de cabeça e do
corpo dos pacientes. A utilização da CRI pode ser efetuada em diferentes
situações em ambiente real e simulado e um jogo sério foi desenvolvido
permitindo especificar um conjunto de tarefas a ser realizado pelos
utilizadores. Os dados foram analisados recorrendo a métodos de extração de
conhecimento, de modo a obter o modelo dos utilizadores. Usando os
resultados obtidos pelo sistema de classificação, foi criada uma metodologia
que permite selecionar a melhor interface e linguagem de comando da cadeira
para cada utilizador.
A avaliação para validação da abordagem foi realizada no âmbito do Projeto
FCT/RIPD/ADA/109636/2009 - "IntellWheels - Intelligent Wheelchair with
Flexible Multimodal Interface". As experiências envolveram um vasto conjunto
de indivíduos que sofrem de diversos níveis de deficiência, em estreita
colaboração com a Escola Superior de Tecnologia de Saúde do Porto e a
Associação do Porto de Paralisia Cerebral. Os dados recolhidos através das
experiências de navegação na CRI foram acompanhados por questionários
preenchidos pelos utilizadores. Estes dados foram analisados estatisticamente,
a fim de provar a eficácia e usabilidade na adequação da interface da CRI ao
utilizador. Os resultados mostraram, em ambiente simulado, um valor de
usabilidade do sistema de 67, baseado na opinião de uma amostra de
pacientes que apresentam os graus IV e V (os mais severos) de Paralisia
Cerebral. Foi também demonstrado estatisticamente que a interface atribuída
automaticamente pela ferramenta tem uma avaliação superior à sugerida pelos
técnicos de Terapia Ocupacional, mostrando a possibilidade de atribuir
automaticamente uma linguagem de comando adaptada a cada utilizador.
Experiências realizadas com distintos modos de controlo revelaram a
preferência dos utilizadores por um controlo compartilhado com um nível de
ajuda associado ao nível de constrangimento do paciente. Em conclusão, este
trabalho demonstra que é possível adaptar automaticamente uma CRI ao
utilizador com claros benefícios a nível de usabilidade e segurança.The importance and concern given to the autonomy and independence of
elderly people and patients suffering from some kind of disability has been
growing significantly in the last few decades. Intelligent wheelchairs (IW) are
technologies that can increase the autonomy and independence of this kind of
population and are nowadays a very active research area. However, the
adaptations to users’ specificities and experiments with real users are topics
that lack deeper studies.
The intelligent wheelchair, developed in the context of the IntellWheels project,
is controlled at a high-level through a flexible multimodal interface, using voice
commands, facial expressions, head movements and joystick as its main input
modalities. This work intended to develop a system enabling the automatic
adaptation, to the user characteristics, of the previously developed intelligent
wheelchair.
A methodology was created enabling the creation of a user model. The
research was based on the development of a data gathering system, enabling
the collection and storage of data from voice commands, facial expressions,
head and body movements from several patients with distinct disabilities such
as Cerebral Palsy. The wheelchair can be used in different situations in real
and simulated environments and a serious game was developed where
different tasks may be performed by users.
Data was analysed using knowledge discovery methods in order to create an
automatic patient classification system. Based on the classification system, a
methodology was developed enabling to select the best wheelchair interface
and command language for each patient.
Evaluation was performed in the context of Project FCT/RIPD/ADA/109636/
2009 – “IntellWheels – Intelligent Wheelchair with Flexible Multimodal
Interface”. Experiments were conducted, using a large set of patients suffering
from severe physical constraints in close collaboration with Escola Superior de
Tecnologia de Saúde do Porto and Associação do Porto de Paralisia Cerebral.
The experiments using the intelligent wheelchair were followed by user
questionnaires. The results were statistically analysed in order to prove the
effectiveness and usability of the adaptation of the Intelligent Wheelchair
multimodal interface to the user characteristics. The results obtained in a
simulated environment showed a 67 score on the system usability scale based
in the opinion of a sample of cerebral palsy patients with the most severe cases
IV and V of the Gross Motor Function Scale. It was also statistically
demonstrated that the data analysis system advised the use of an adapted
interface with higher evaluation than the one suggested by the occupational
therapists, showing the usefulness of defining a command language adapted to
each user. Experiments conducted with distinct control modes revealed the
users' preference for a shared control with an aid level taking into account the
level of constraint of the patient. In conclusion, this work demonstrates that it is
possible to adapt an intelligent wheelchair to the user with clear usability and
safety benefits