22 research outputs found
Real-Time Trajectory Generation and Control of a Semi-Omnidirectional Mobile Robot
When controlling a wheeled mobile robot with four independently steerable driving wheels, the control of the wheel coordination must be handled. Both the direction and velocity of the wheels must be coordinated to allow for proper operation of the robot. The focus of this work is on the coordination of the wheel directions. Such coordination is mostly done by solving constraint equations of the system kinematics, but when the demands on the coordination are high, it is sometimes necessary to include the steering dynamics in the coordination control. With dynamics included the complexity of the wheel coordination increases, since constraints dependent on required angle changes and current velocities must be fulfilled. By calculating the dynamic limitations in each control cycle, the steering limit for the whole wheel base within the current control cycle can be found. With use of such wheel base limit, followable and coordinated wheel trajectories can be generated online. This thesis includes the construction of a dynamic model for inclusion of the steering dynamic limitations affecting the performance the most, the construction of the online trajectory generation idea, as well as implementation and validation on the real target wheeled mobile robot platform
College of Engineering Senior Design Competition Fall 2012
Senior Design Experience
Part of every UNLV engineering student\u27s academic experience, the Senior Design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs and prototypes a product in this required element of the curriculum. Working in teams, the senior design project encourages students to use everything learned in the engineering and computer design programs to create a practical, real world solution to an engineering challenge.
Beyond the classroom ...
Because of the requirement to work in teams, students also build good communication skills, presentation skills and even business writing skills. They also have to source and purchase the materials for the prototypes themselves, giving them real-world budgeting experience-all necessary skills to have in the business world
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