This thesis explores the field of hand exoskeleton robotic systems with slip detection and its applications. It presents the design and control of the intelligent sensing and force- feedback exoskeleton robotic (iSAFER) glove to create a system capable of intelligent object grasping initiated by detection of the user’s intentions through motion amplification. Using a combination of sensory feedback streams from the glove, the system has the ability to identify and prevent object slippage, as well as adapting grip geometry to the object properties. The slip detection algorithm provides updated inputs to the force controller to prevent an object from being dropped, while only requiring minimal input from a user who may have varying degrees of functionality in their injured hand. This thesis proposes the use of a high dynamic range, low cost conductive elastomer sensor coupled with a negative force derivative trigger that can be leveraged in order to create a controller that can intelligently respond to slip conditions through state machine architecture, and improve the grasping robustness of the exoskeleton. The mechanical and electrical improvements to the previous design, the sensing and force- feedback exoskeleton robotic (SAFER) glove, are described while details of the controller design and the proposed assistive and rehabilitative applications are explained. Experimental results confirming the validity of the proposed system are also presented. In closing, this thesis concludes with topics for future exploration. / Master of Science / Exoskeletons are robotic systems that have rigid external covering, such as links, joints, and/or soft artificial tendons or muscles, for the desired body part to provide support and/or protection. These are typically used to enhance power and strength, provide rehabilitation and assistance, and teleoperate other robots from a distance. While the US Army developed exoskeletons for strengthening purposes, another potential purpose of exoskeletons, which is serving medical needs, such as rehabilitation, attracted a lot of attention. Among numerous illnesses and injuries that may lead to impaired hand functionality, the U.S. Department of Health and Human Services estimated that approximately 470,000 people survive strokes every year in the United States and require continuous rehabilitation to recover their motor functions. Though medical professionals believe that the intensity and duration of rehabilitation is the key for maximizing the rate of recovery, it is often limited due to many reasons, such as cost or difficulty in attending rehabilitation sessions. To augment the availability and quality of rehabilitation, the study of exoskeletons has earned popularity. Beyond the capability of providing simple movements, such as passive rehabilitation, many scientists researched to provide active rehabilitation, which involves active participation from the patients. Furthermore, detecting the patient’s intention to activate the rehabilitation glove became a topic of interest, and many types of sensors were utilized in research. This thesis explores the design and control of the intelligent sensing and force- feedback exoskeleton robotic (iSAFER) glove, which detects the user’s intentions to activate the system through motion amplification. The iSAFER glove performs soft initial grasp until the fingers touch an object. After the object is gently grabbed and lifted, the grasp is autonomously adjusted through slip detection until there is no more slip. To facilitate this idea, a low cost force sensor was created and leveraged to improve the grasping control of the exoskeleton. The mechanical and electrical improvements to the previous design, the sensing and force-feedback exoskeleton robotic (SAFER) glove, are described while details of the controller design and the proposed assistive and rehabilitative applications are explained. Experimental results confirming the validity of the proposed system are also presented. In closing, this thesis concludes with topics for future exploration.

This thesis explores the field of robotic hand exoskeletons and their applications. These systems have emerged in popularity over the years, due to their potentials to advance the medical field as assistive and rehabilitation devices, and the field of virtual reality as haptic gloves. Although much progress has been made, hand exoskeletons are faced with several design challenges that are hard to overcome without having some tradeoffs. These challenges include: (1) the size and weight of the system, which can affect both the comfort of wearing it and its portability, (2) the ability to impose natural joint angle relationships among the user's fingers and thumb during grasping motions, (3) safety in terms of limiting the range of motions produce by the system to that of the natural human hand and ensuring the mechanical design does not cause harm or injury to the user during usage, (4) designing a device that is user friendly to use, and (5) the ability to effectively perform grasping motions and provide sensory feedback for the system to be applicable in various application fields. In order to address these common issues of today's state-of-the-art hand exoskeleton systems, this thesis proposes a mechanism design for a novel hand exoskeleton and presents the integration of several prototypes. The proposed hand exoskeleton is designed to assist the user with grasping motions while maintaining a natural coupling relationship among the finger and thumb joints to resemble that of a normal human hand. The mechanism offers the advantage of being small-size and lightweight, making it ideal for prolong usage. Several applications are discussed to highlight the proposed hand exoskeleton functionalities in processing sensory information, such as position and interactive forces. / MS / Hand exoskeletons are wearable devices that are designed to augment, reinforce, and/or restore hand performances and movements among the fingers and thumb. These hand exoskeleton systems have emerged in popularity within the medical field, where they serve as rehabilitation devices or assistive gloves, and within the field of virtual reality as haptic devices. Throughout the years, many hand exoskeleton designs have been proposed and even developed further into commercial products. Unfortunately, there still exist many design challenges for making an efficient and feasible hand exoskeleton without experiencing major tradeoffs. Some of the common challenges include designing a hand exoskeleton that is small in size, lightweight, and able to achieving natural grasping motions efficiently. As an attempt to overcome these design challenges, the work of this thesis presents a mechanism design for a novel hand exoskeleton that can serve as a general purpose glove across several applications. The design of the mechanism is described in detail with preliminary analysis. In addition, this thesis presents the design and development of several prototypes, which were made by extending the mechanism into fully integrated systems. The experimental validations of these prototypes are presented as well as their application potentials. To conclude the thesis, a discussion of the on-going future work is given.

Modern Rapid Prototyping (RP) technology has been available for more than a decade and has aided in shortening product development times and costs in the manufacturing sector. Stereolithography (SL), the most mature of RP technology, has primarily been used to build small to medium sized parts although there are largescale applications i.e. the automotive industry that uses “mammoth SLA”. Recent developments in SL have been aimed at increasing the speed of the additive process of most SL apparatus (SLA). Developments include the chemistry of photopolymer resins, integral-curing processes as opposed to vector-by-vector processes, and what is now called microstereolithography. Integral curing has been made possible by the advent of dynamic masking generators such as liquid crystal displays (LCDs) and digital micromirror devices (DMDs). Much of the theory for this new layering process has been applied to the micro-scale and awaits application for medium to large sized parts. The Limaye Model was applied to a microstereolithography apparatus (µSLA) and used as a process planning method for curing dimensionally accurate micro parts. Examination of the results of this mathematical model shows an irradiance map simulating the irradiances on the resin surface. The light is expected to attenuate from the central axis according to a measured irradiance curve. Improvements can be made to the Limaye Model to make it applicable for the process planning of medium to large parts. It is the aim of this research to present an improved mathematical model of the Limaye Model, so that a given irradiance map will produce an evenly distributed irradiance and account for errors in the optical imaging system. It is hoped that the field of exposure of 200mm x 270mm or larger will be achieved.

Mechatronic systems encompass a wide range of disciplines, including mechanical and electrical engineering, and hence the development process for mechatronic system is collaborative in nature. Currently the collaborative development of mechatronic systems is inefficient and error-prone because contemporary design environments do not allow sufficient information flow of design and manufacturing data across different engineering domains. Mechatronic systems need to be designed in an integrated fashion allowing designers from multiple engineering domains to receive updates regarding design modifications throughout the design process. One approach to facilitate integrated design of mechatronic systems is to integrate mechanical with electrical engineering CAD systems. Currently there exist numerous techniques that were developed to support various levels of integration between CAD/CAE systems. Standardized data exchange formats, e.g., STEP and IGES, support information exchange between various different CAD and PDM systems. Multi-Representation Architecture (Peak et al.) supports the integration of geometric information in CAD tools with analysis information in CAE tools. Other integration techniques include the Core Product Model (developed at NIST), Active Semantic Networks (Roller et al.), Constraint Linking Bridge (Kleiner et al.), and others. All these techniques have their areas of focus as well as research gaps that need to be covered. One area that needs research attention is the information exchange between mechanical and electrical domains, which is the focus of this thesis. In this thesis, the information exchange between mechanical and electrical domains is explored from two perspectives: conceptual design perspective, in which constraint relationship between attributes of mechanical and electrical components is identified and classified based on the physical forms, functions, and behavior of the mechatronic system; system realization perspective, in which the identified constraints are modeled for propagation between MCAD and ECAD systems. SysML is used to model the constraints between mechanical and electrical components. By means of an illustrative example (a robot arm), the constraint modeling and propagation developed in my thesis are demonstrated and implemented utilizing a MCAD system (SolidWorks) and an ECAD system (EPLAN Electric P8).

<p dir="ltr">Over 150,000 people undergo lower-extremity amputations yearly in the United States. In recent years, multiple efforts have been made to improve the human-robot interaction between amputees and active lower limb prostheses. Using lightweight wearable technologies has been a viable solution to implement algorithms that can estimate gait kinematics and prosthesis users’ intent. Examples of wearable technologies include inertial measurement units, strain gauges, and electromyography sensors. Kinematic and force data is inputted into an Error-State Kalman filter to estimate the inversion-eversion, external-internal, and dorsiflexion-plantarflexion ankle angle. The filter tracked the ankle angle with an accuracy of 0.7724°, 0.8826°, and 1.3520°, respectively. The gait phase was estimated using a linear regression model based on a shank kinematics ground truth pattern with an average normalized accuracy of 97.79 %. A numerical simulation of a gait emulator in the form of a 3-Revolute-Prismatic-Revolute (3-RPR) manipulator. The gait emulator can test lower limb prostheses independent of human subjects, eliminating many hurdles associated with human subject testing. The manipulator was simulated with two control strategies: a traditional PID and a hybrid PID + Active Force Control controller (AFC). The hybrid PID+AFC provided higher accuracy in tracking the desired end-effector trajectory due to improved disturbance rejection. A low-cost surface electromyography (sEMG) platform was developed to robustly acquire sEMG signals, with an overall component cost of 35.06 US$. The sEMG platform integrates directly into a Micro:bit microcontroller through an expansion board. During testing with human subjects, sEMG Micro:bit platform had a reported average signal-to-noise ratio of 24.7 dB.</p>

<div>Polymer nanocomposites (PNC) have an excellent potential for in-situ strain sensing applications in static and dynamic loading scenarios. These PNCs have a polymer matrix of polyvinylidene fluoride (PVDF) with a conductive filler of multi-walled carbon nanotubes (MWCNT) and have both piezoelectric and piezoresistive characteristics. Generally, this composite would accurately measure either low-frequency dynamic strain using piezoresistive characteristic or high-frequency dynamic strains using piezoelectric characteristics of the MWCNT/PVDF film sensor. Thus, the frequency bands of the strain sensor are limited to either piezoresistive or piezoelectric ranges. In this study, a novel weighted fusion technique, called Piezoresistive/Piezoelectric Fusion (PPF), is proposed to combine both piezoresistive and piezoelectric characteristics to capture the wide frequency bands of strain measurements in real-time. This fuzzy logic (FL)-based method combines the salient features (i.e., piezoresistive and piezoelectric) of the nanocomposite sensor via reasonably accurate models to extend the frequency range over a wider band. The FL determines the weight of each signal based on the error between the estimated measurements and the actual measurements. These weights indicate the contribution of each signal to the final fused measurement. The Fuzzy Inference System (FIS) was developed using both optimization and data clustering techniques. In addition, a type-2 FIS was utilized to overcome the model’s uncertainty limitations. The developed PPF methods were verified with experimental data at different dynamic frequencies that were obtained from existing literature. The fused measurements of the MWCNT/PVDF were found to correlate very well with the actual strain, and a high degree of accuracy was achieved by the subtractive clustering PPF’s FISs algorithm. <br></div><div><br></div><div>3D force sensors have proven their effectiveness and relevance for robotics applications. They have also been used in medical and physical therapy applications such as surgical robots and Instrument Assisted Soft Tissue Manipulation (IASTM). The 3D force sensors have been utilized in robot-assisted surgeries and modern physical therapy devices to monitor the 3D forces for improved performances. The 3D force sensor performance and specifications depend on different design parameters, such as the structural configuration, placement of the sensing elements, and load criterion. In this work, different bioinspired structure configurations have been investigated and analyzed to obtain the optimal 3D force sensor configuration in terms of structural integrity, compactness, the safety factor, and strain sensitivity. A Finite Element Analysis (FEA) simulation was used for the analysis to minimize the time of the development cycle.</div><div><br></div><div><br></div><div>A tree branch design was used as the 3D force sensor’s elastic structure. The structure was made of aluminum with a laser-cutting fabrication process. The PVDF/MWCNT films contained piezoresistive and piezoelectric characteristics that allowed for static/low strain measurements and dynamic strain measurements, respectively. Two compositions with 0.1 wt.% and 2 wt.% PVDF/MWCNT sensing elements were selected for piezoelectric and piezoresistive strain measurements, respectively. These characteristic measurements were investigated under different vibration rates in a supported beam experiment. The 3D force sensor was tested under dynamic excitation in the Z-direction and the X-direction. A Direct Piezoresistive/Piezoelectric Fusion (DPPF) method was developed by fusing the piezoresistive and piezoelectric measurements at a given frequency that overcomes the limited frequency ranges of each of the strain sensor characteristics. The DPPF method is based on a fuzzy inference system (FIS) which is constructed and tuned using the subtractive clustering technique. Different nonlinear Hammerstein-Wiener (nlhw) models were used to estimate the actual strain from piezoresistive and piezoelectric measurements at the 3D force sensor. The DPPF method was tested and validated for different strain signal types using presumed Triangle and Square signal waves data. The DPPF has proven its effectiveness in fusing piezoresistive and piezoelectric measurements with different types of signals. In addition, an Extended Direct Piezoresistive/Piezoelectric Fusion (EPPF) is introduced to enhance the DPPF method and perform the fusion in a range of frequencies instead of a particular one. The DPPF and EPPF methods were implemented on the 3D force sensor data, and the developed fusion algorithms were tested on the proposed 3D force sensor experimental data. The simulation results show that the proposed fusion methods have been effective in achieving lower Root Mean Square Error (RMSE) than those obtained from the tuned nlhw models at different operating frequencies.</div>

<p dir="ltr">This research project aims to develop a robotic platform capable of drilling horizontal laterals from existing wellbores, offering data-guided steering and control features using information captured by sensors. The project provides an opportunity to expand the application of downhole drilling robots toward semi-autonomous operations in existing fields, especially those with declining production. Mature fields represent a global resource, and even modest hydrocarbon reserves additions are substantial to keep up the energy demand, having positive economic and environmental impacts. Available lateral drilling techniques do not fit the constraints offered by the challenge; moreover, they are not cost-effective.</p><p dir="ltr">The project will be organized into three phases to accomplish this developmental study. First, design criteria and key performance aspects will be identified and established to design a self-propelled robotic prototype capable of drilling lateral sections from an existing wellbore with an internal diameter of 4” to 6”. The creation of lateral sections can potentially add hydrocarbon reserves taking advantage of an already-drilled vertical section of a mature field. Second, the design of the prototype will take place, along with the design of a sub-surface communication and control system. The third phase is manufacturing and subsystems integration, finishing with a pilot test in a controlled environment. Based on the pilot testing results, design optimization will occur. Finally, a field version will be designed, and IP (Intellectual Property) disclosures and plans for commercialization will be identified and addressed.</p>

<p>The academic subject of mechatronics has been definedpreviously in numerous publications. This study aims atanalyzing mechatronics by using categories developed within theeducational science of Didactics. The result of the analysis,that relies on data from mechatronics education at KTH andother universities, shows that the identity of mechatronics canbe described as thematic, and the legitimacy as functional,which gives implications for the questions of communication andselection: what should be taught, and how. This is combinedwith a study of the evolution of the subject of mechatronics,where it is possible to see the gradually changing identity,from a combination of a number of disciplinary subjects to onethematic subject.</p><p>The first part of the thesis concludes that mechatronics isautonomous, thematic and functional. Teaching and learningmechatronics according to the identity and legitimacy of thesubject benefits from collaborative, experimental andinternational settings. The functional legitimacy todayrequires the collaborative and the international setting,meaning that the mechatronics employer requires these skillswhen employing a mechatronic engineer. Further, an exemplifyingselection requires the experimental setting, in particular whencomparing a representative selection with the reproduction ofknowledge, and an exemplifying selection with the creation ofknowledge.</p><p>To conclude, there are a number of important aspects to takeinto account when teaching and learning mechatronics. Three ofthese aspects, collaborative, experimental and internationalare suggested as important, and also a direct consequence ofthe identity of mechatronics. This thesis shows that thesethree aspects are indeed possible to integrate intomechatronics education, which will benefit greatly fromthis.</p> / QC 20100609

Propõe o modelo de referência para o processo de desenvolvimento de produtos mecatrônicos, denominado MRM, que consiste em um conjunto de melhores práticas sistematizadas das bibliografias de desenvolvimento de produtos, eletrônica, engenharia de software e projeto de engenharia. Discute o conceito de mecatrônica propondo um conjunto de componentes que caracterizariam esses produtos. Utiliza conceitos de modelagem de empresas para apresentar o MRM. Estrutura o desenvolvimento de produtos mecatrônicos em doze fases intercaladas por pontos de decisão e caracterizadas pelos documentos gerados no final de cada uma. Elabora uma metodologia de aplicação do modelo com base no conceito de capabilidade de áreas de processo. Descreve a aplicação do MRM em uma empresa que desenvolve produtos mecatrônicos. A aplicação abrange todas as fases do modelo e é avaliada por meio de entrevistas com os principais usuários das melhorias aplicadas na empresa. O trabalho utiliza dois procedimentos básicos de pesquisa: a análise de conteúdo no estudo da bibliografia utilizada na pesquisa; e a pesquisa-ação como método de aplicação do modelo. O uso do MRM permitiu à empresa a consecução da certificação ISO 9000 para seu processo de desenvolvimeto de produtos (PDP), assim como o registro de produtos mecatrônicos em órgãos regulatórios nacionais e internacinais. A avaliação realizada ao final da aplicação do trabalho mostra que o modelo melhorou indicadores de custo dos projetos, controle de prazos ao longo dos projetos, assim como reduziu as reclamações dos setores de manufatura com relação às especificações geradas pela engenharia. Os entrevistados consideraram que a capacidade de integração de pessoas novas aos projetos em desenvolvimento é a melhoria mais significativa conseguida com a aplicação do MRM na empresa. Os resultados permitem considerar o modelo coerente com a bibliografia de PDP, indicam que a utilização de modelos de referência podem melhorar o PDP de uma empresa e demonstram haver uma relação entre o aumento da capabilidade de um processo e a melhoria de seus indicadores de desempenho / This thesis proposes the reference model for the mechatronic product development process, called MRM, i.e. a set of best practices about product development, engineering design, electronics and software engineering. It discusses the concept of mechatronic and proposes a set of elements that characterize this kind of products. It takes into account enterprise modeling techniques to present MRM. MRM framework is composed by twelve phases with well defined checkpoints and outputs. The work describes a methodology to apply MRM based on process areas capability indexes. It presents a MRM application in a company that develops mechatronic products. The application is evaluated based on interviews with model users. Research methods are content analysis and action research. The skilled results are ISO 9000 certification and product registration. Inteviews show that cost and schedule control were improved by MRM use. Manufacture disfuctions based on bad engineering specifications were decresed. The evaluation suggests that new engineers and technician integration is the best result of model application. These results allow to verify the effectiveness of reference models to improve product development and demonstrate that there is a relationship between increments of process capability and improvements critical succes factors rates

novel approach to extend the decision-making capabilities of unmanned surface vehicles (USVs) is presented in this work. A multi-objective framework is described where separate controllers command different behaviors according to a desired trajectory. Three behaviors are examined – transiting, station-keeping and reversing. Given the desired trajectory, the vehicle is able to autonomously recognize which behavior best suits a portion of the trajectory. The USV uses a combination of a supervisory switching control structure and a reinforcement learning algorithm to create a hybrid deliberative and reactive approach to switch between controllers and actions. Reinforcement learning provides a deliberative method to create a controller switching policy, while supervisory switching control acts reactively to instantaneous changes in the environment. Each action is restricted to one controller. Due to the nonlinear effects in these behaviors, two underactuated backstepping controllers and a fully-actuated backstepping controller are proposed for each transiting, reversing and station-keeping behavior, respectively, restricted to three degrees of freedom. Field experiments are presented to validate this system on the water with a physical USV platform under Sea State 1 conditions. Main outcomes of this work are that the proposed system provides better performance than a comparable gain-scheduled nonlinear controller in terms of an Integral of Absolute Error metric. Additionally, the deliberative component allows the system to identify dynamically infeasible trajectories and properly accommodate them. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection