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Synthesis of continuous whole-body motion in hexapod robot for humanitarian demining
This thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University LondonIn the context of control, the motion of a legged robot is very challenging compared
with traditional fixed manipulator. Recently, many researches have been conducted
to control the motion of legged robot with different techniques. On the other hand,
manipulation tasks have been addressed in many applications. These researches solved
either the mobility or the manipulation problems, but integrating both properties
in one system is still not available. In this thesis, a control algorithm is presented
to control both locomotion and manipulation in a six legged robot. Landmines
detection process is considered as a case study of this project to accelerate the mine
detection operation by performing both walking and scanning simultaneously. In
order to qualify the robot to perform more tasks in addition to the walking task,
the joint redundancy of the robot is exploited optimally. The tasks are arranged
according to their importance to high level of priority and low level of priority. A new
task priority redundancy resolution technique is developed to overcome the effect
of the algorithmic singularities and the kinematic singularity. The computational
aspects of the solution are also considered in view of a real-time implementation.
Due to the dynamic changes in the size of the robot motion space, the algorithm
has the ability to make a trade-off between the number of achieved tasks and the
imposed constraints. Furthermore, an appropriate hierarchy is imposed in order
to ensure an accurate decoupling between the executed tasks. The dynamic effect
of the arm on the overall performance of the robot is attenuated by reducing the
optimisation variables. The effectiveness of the method is evaluated on a Computer
Aided Design (CAD) model and the simulations of the whole operation are conducted
using MATLAB and SimMechanics.Iraqi ministry of Higher Education and Scientific Researc
Mechatronic Systems
Mechatronics, the synergistic blend of mechanics, electronics, and computer science, has evolved over the past twenty five years, leading to a novel stage of engineering design. By integrating the best design practices with the most advanced technologies, mechatronics aims at realizing high-quality products, guaranteeing at the same time a substantial reduction of time and costs of manufacturing. Mechatronic systems are manifold and range from machine components, motion generators, and power producing machines to more complex devices, such as robotic systems and transportation vehicles. With its twenty chapters, which collect contributions from many researchers worldwide, this book provides an excellent survey of recent work in the field of mechatronics with applications in various fields, like robotics, medical and assistive technology, human-machine interaction, unmanned vehicles, manufacturing, and education. We would like to thank all the authors who have invested a great deal of time to write such interesting chapters, which we are sure will be valuable to the readers. Chapters 1 to 6 deal with applications of mechatronics for the development of robotic systems. Medical and assistive technologies and human-machine interaction systems are the topic of chapters 7 to 13.Chapters 14 and 15 concern mechatronic systems for autonomous vehicles. Chapters 16-19 deal with mechatronics in manufacturing contexts. Chapter 20 concludes the book, describing a method for the installation of mechatronics education in schools
Anatomic Characterization and Profilometry of Tissues with Natural Shape: A Real-time Approach for Robotic-Assisted Minimally Invasive Surgery
This master thesis is divided into two major sections. First, anatomic characterization and profilometry of tissues with natural shape: a real-time approach for robotic-assisted minimally invasive surgery (RMIS); and second, design and characterization of a novel tactile array sensor capable of differentiating among different viscoelastic tissues that exhibit time-dependent behaviour.
The first part of this thesis is focused on a tissue characterization system for RMIS applications. RMIS has gained immense popularity with the advent of high-precision robotic systems. The lack of haptic feedback, however, is considered as being one of the main drawbacks of present-day RMIS systems. In order to compensate for this deficiency, a novel tissue characterization system is proposed which is inspired from the human haptic system. Hence, kinesthetic and tactile feedback which are constitutive components of human haptic system are used to characterize naturally shaped tissues. Toward this goal, a 5-degree-of-freedom robot which is called Catalys5 is equipped with a ball caster force-cell. The system is used to simulate robotic surgery maneuvers in which an admittance control approach is implemented to design the force feedback controller. The proposed method characterizes naturally shaped tissues, which is capable of touching and palpating to: a) Identify the 2D or 3D surface profile of the target tissue (profilometry), b) Measure the modulus of elasticity of any desired point on the tissue’s surface, c) Find and map the location of any lump in the tissue, and d) Map hardness distribution around the lump.
Initially, silicon-rubber materials were used to build tissue phantoms with different curvatures and degrees of softness. The surface profiles were obtained using the developed profilometry algorithm and validated using a 3D scanner. In addition, several experiments were conducted on bovine tissues to evaluate all above mentioned capabilities of the system. The results of experiments on real tissues were also compared to those that are available in current literature. The results indicate that the proposed approach can be used for reliable material characterization for RMIS application.
The second part of this thesis is focused on developing an array tactile sensor for distinguishing softness of viscoelastic tissues with time-dependent behaviour for use in MIS and RMIS. Review of literature on tactile sensors reveals that the vast majority deals with determining the applied contact force and object elasticity. In this research, a novel idea is proposed in which a tactile sensor array can measure rate of displacement in addition to force and displacement of any viscoelastic material during the course of a single touch. In order to verify this new array sensor, several experiments were conducted on a range of biological tissues. It was concluded that this novel tactile sensor can distinguish among the softness of real biological tissue with time-dependent behaviour
Using MapReduce Streaming for Distributed Life Simulation on the Cloud
Distributed software simulations are indispensable in the study of large-scale life models but often require the use of technically complex lower-level distributed computing frameworks, such as MPI. We propose to overcome the complexity challenge by applying the emerging MapReduce (MR) model to distributed life simulations and by running such simulations on the cloud. Technically, we design optimized MR streaming algorithms for discrete and continuous versions of Conway’s life according to a general MR streaming pattern. We chose life because it is simple enough as a testbed for MR’s applicability to a-life simulations and general enough to make our results applicable to various lattice-based a-life models. We implement and empirically evaluate our algorithms’ performance on Amazon’s Elastic MR cloud. Our experiments demonstrate that a single MR optimization technique called strip partitioning can reduce the execution time of continuous life simulations by 64%. To the best of our knowledge, we are the first to propose and evaluate MR streaming algorithms for lattice-based simulations. Our algorithms can serve as prototypes in the development of novel MR simulation algorithms for large-scale lattice-based a-life models.https://digitalcommons.chapman.edu/scs_books/1014/thumbnail.jp
Whole-hand input
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Architecture, 1992.Includes bibliographical references (p. 219-233).by David Joel Sturman.Ph.D
ENABLING HARDWARE TECHNOLOGIES FOR AUTONOMY IN TINY ROBOTS: CONTROL, INTEGRATION, ACTUATION
The last two decades have seen many exciting examples of tiny robots from a few cm3 to less than one cm3. Although individually limited, a large group of these robots has the potential to work cooperatively and accomplish complex tasks. Two examples from nature that exhibit this type of cooperation are ant and bee colonies. They have the potential to assist in applications like search and rescue, military scouting, infrastructure and equipment monitoring, nano-manufacture, and possibly medicine.
Most of these applications require the high level of autonomy that has been demonstrated by large robotic platforms, such as the iRobot and Honda ASIMO. However, when robot size shrinks down, current approaches to achieve the necessary functions are no longer valid. This work focused on challenges associated with the electronics and fabrication. We addressed three major technical hurdles inherent to current approaches: 1) difficulty of compact integration; 2) need for real-time and power-efficient computations; 3) unavailability of commercial tiny actuators and motion mechanisms. The aim of this work was to provide enabling hardware technologies to achieve autonomy in tiny robots.
We proposed a decentralized application-specific integrated circuit (ASIC) where each component is responsible for its own operation and autonomy to the greatest extent possible. The ASIC consists of electronics modules for the fundamental functions required to fulfill the desired autonomy: actuation, control, power supply, and sensing. The actuators and mechanisms could potentially be post-fabricated on the ASIC directly. This design makes for a modular architecture.
The following components were shown to work in physical implementations or simulations: 1) a tunable motion controller for ultralow frequency actuation; 2) a nonvolatile memory and programming circuit to achieve automatic and one-time programming; 3) a high-voltage circuit with the highest reported breakdown voltage in standard 0.5 μm CMOS; 4) thermal actuators fabricated using CMOS compatible process; 5) a low-power mixed-signal computational architecture for robotic dynamics simulator; 6) a frequency-boost technique to achieve low jitter in ring oscillators. These contributions will be generally enabling for other systems with strict size and power constraints such as wireless sensor nodes
Development of Piezoresistive Tactile Sensors and a Graphical Display System for Minimally Invasive Surgery and Robotics
Development of Piezoresistive Tactile Sensors and a Graphical Display System for Minimally Invasive Surgery and Robotics
Masoud Kalantari, PhD
Concordia University, 2013
This PhD work presents a new tactile and feedback systems for minimally invasive
surgery (MIS)and robotics. The thesis is divided into two major sections: the tactile
sensing system, and the graphical display system.
In the tactile sensing system, piezoresistive materials are used as measuring elements.
The first part of the thesis is focused on the theoretical modeling of piezoresistive
sensing elements, which are semiconductive polymer composites. The model
predicts the piezoresistive behavior in semiconductive polymer composites, including
their creep effect and contact resistance. A single force sensing resistor (FSR) is, then, developed by using the semiconductive polymer composite materials. The developed
FSR is used in the structure of a novel tactile sensor as the transduction element.
The developed tactile sensor is designed to measure the difference in the hardness
degree of soft tissues. This capability of the sensor helps surgeons to distinguish different types of tissues involved in the surgery. The tactile sensor is integrated on the extremity of a surgical tool to provide tactile feedback from the interaction between surgical instruments and the tissue during MIS. Mitral valve annuloplasty repair by MIS is of our particular interest to be considered as a potential target for the use of the developed tactile sensor. In the next step, the contact interaction of the tactile sensor with soft tissues is modelled, parametrically. Viscoelastic interaction is considered between the tactile sensor and atrial tissue in annuloplasty mitral valve repair; and a parametric solution for the viscoelastic contact is achieved.
In addition to the developed sensor, a novel idea regarding measuring the indentation
rate, in addition to measuring force and displacement is implemented in a new
design of an array tactile sensor. It is shown that the indentation-rate measurement is
an important factor in distinguishing the hardness degree of tissues with viscoelastic
behaviour.
The second part of the thesis is focused on the development of a three-dimensional
graphical display that provides visual palpation display to any surgeon performing
robotic assisted MIS. Two matrices of the developed piezoresistive force sensor are
used to palpate the tissue and collect the tactile information. The collected data are processed with a new algorithm and graphically rendered in three dimensions.
Consequently, the surgeon can determine the presence, location, and the size of any
hidden superficial tumor/artery by grasping the target tissue in a quasi-dynamic way
The Irresistible Animacy of Lively Artefacts
This thesis explores the perception of ‘liveliness’, or ‘animacy’, in robotically driven artefacts. This perception is irresistible, pervasive, aesthetically potent and poorly understood. I argue that the Cartesian rationalist tendencies of robotic and artificial intelligence research cultures, and associated cognitivist theories of mind, fail to acknowledge the perceptual and instinctual emotional affects that lively artefacts elicit. The thesis examines how we see artefacts with particular qualities of motion to be alive, and asks what notions of cognition can explain these perceptions. ‘Irresistible Animacy’ is our human tendency to be drawn to the primitive and strangely thrilling nature of experiencing lively artefacts. I have two research methodologies; one is interdisciplinary scholarship and the other is my artistic practice of building lively artefacts. I have developed an approach that draws on first-order cybernetics’ central animating principle of feedback-control, and second-order cybernetics’ concerns with cognition. The foundations of this approach are based upon practices of machine making to embody and perform animate behaviour, both as scientific and artistic pursuits. These have inspired embodied, embedded, enactive, and extended notions of cognition. I have developed an understanding using a theoretical framework, drawing upon literature on visual perception, behavioural and social psychology, puppetry, animation, cybernetics, robotics, interaction and aesthetics. I take as a starting point, the understanding that the visual cortex of the vertebrate eye includes active feature-detection for animate agents in our environment, and actively constructs the causal and social structure of this environment. I suggest perceptual ambiguity is at the centre of all animated art forms. Ambiguity encourages natural curiosity and interactive participation. It also elicits complex visceral qualities of presence and the uncanny. In the making of my own Lively Artefacts, I demonstrate a series of different approaches including the use of abstraction, artificial life algorithms, and reactive techniques
Biomimetic Based Applications
The interaction between cells, tissues and biomaterial surfaces are the highlights of the book "Biomimetic Based Applications". In this regard the effect of nanostructures and nanotopographies and their effect on the development of a new generation of biomaterials including advanced multifunctional scaffolds for tissue engineering are discussed. The 2 volumes contain articles that cover a wide spectrum of subject matter such as different aspects of the development of scaffolds and coatings with enhanced performance and bioactivity, including investigations of material surface-cell interactions
Life Sciences Program Tasks and Bibliography for FY 1997
This document includes information on all peer reviewed projects funded by the Office of Life and Microgravity Sciences and Applications, Life Sciences Division during fiscal year 1997. This document will be published annually and made available to scientists in the space life sciences field both as a hard copy and as an interactive internet web page