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Inference and criticism of dynamical models to accelerate microrobot designLivitz, Dimitri Gennady January 2023 (has links)
This thesis seeks to advance the field of microrobotics by leveraging Bayesian principles and computational tools to design system parameters for information gain and microrobot propulsion. Inspired by living cells, the development of mobile robots on the micron scale (microrobots) promises new capabilities for advancing human health, renewable energy, and environmental sustainability. To help pave the way towards this goal we develop practical recipes for applying computational and analytical tools to physics-based dynamical models of our microrobot experiments. We apply methods of criticism and validation to identify robust models for the motion of magnetic particles at curved interfaces, and identify optimal conditions for propulsion in our model system. We then develop tools for identifying optimal experimental conditions for most efficiently learning model parameters. By studying microscale actuation in depth, we seek to provide a roadmap of how to apply these computational tools to other microrobot design challenges, accelerating the scientific process.
In Chapter 1, we focus on the actuation of magnetic particles adsorbed at curved liquid interfaces by external fields, a phenomenon that can be utilized for applications such as droplet mixing or propulsion. To optimize these behaviors, the development and validation of predictive models are essential. We employ Bayesian data analysis as a principled approach to infer model parameters from experimental observations, assess the capabilities of candidate models, and select the most plausible among them. Specifically, we identify and validate a dynamical model which accounts for the effects of gravity and tilting of the particle, a Janus sphere, at the interface. We show how this favored model can predict complex particle trajectories with micron-level accuracy across the range of driving fields considered.
Chapter 2 builds on this modeling to develop the optimal properties of a mobile liquid droplet, driven by an adsorbed magnetic particle. This configuration enables the design of responsive emulsions, which can be actuated by a magnetic field. This work develops the properties of such a swimmer and validates our findings with an experimental realization of a ferromagnetic ellipsoid adsorbed onto a stationary water droplet in decane. Accounting for geometric differences, the model developed in the previous chapter is demonstrated to be accurate for this new system. We find that the configuration of the magnetic moment of our ellipsoid prohibits swimming of the assembly, but if it can be modified during fabrication, propulsion is possible.
In Chapter 3 we show how automated experiments based on Bayesian inference and design can accurately and efficiently characterize another microscale propulsion system, the acoustic field within resonant chambers used to propel acoustic nanomotors. Repeated cycles of observation, inference, and design are guided by a physical model that describes the rate at which levitating particles approach the nodal plane. We show how this iterative process serves to discriminate between competing hypotheses and efficiently converges to accurate parameter estimates using only a few automated experiments. This work demonstrates how Bayesian methods can learn the parameters of nonlinear hierarchical models used to describe video microscopy data of active colloids.
Finally, the forward-looking perspective in Chapter 4 illustrates how best to leverage these techniques and models to provide a path forward for self-guided microrobots. Existing microrobots based on field-driven particles rely on knowledge of the particle position and the target destination to control particle motion through fluid environments. These external control strategies are challenged by limited information and global actuation, where a common field directs multiple robots with unknown positions. We discuss how time-varying magnetic fields can be used to encode self-guided behaviors of magnetic particles conditioned on local environmental cues. Programming these behaviors is framed as a design problem: we seek to identify the design variables (e.g. particle shape, magnetization, elasticity, stimuli-response) that achieve the desired performance in a given environment. We discuss strategies for accelerating the design process using the methods developed in this thesis—including automated experiments, computational models, and statistical inference—as well as other approaches such as machine learning. Based on the current understanding of field-driven particle dynamics and existing capabilities for particle fabrication and actuation, we argue that self-guided microrobots with potentially transformative capabilities are close at hand.
This research offers a unique contribution by demonstrating the practicality and efficiency of Bayesian computational methods in microrobot design, and provides a template that is applicable anywhere that physics-based dynamical models can be used to guide experimental effort.
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Intuitive programming of mobile manipulation applications : A functional and modular GUI architecture for End-User robot programming / Intuitiv programmering av mobil manipulations applikationer : En funktionell och modulär GUI arkitektur för slutanvändares robot programmeringDe Martini, Alessandro January 2021 (has links)
Mobile manipulators are changing the way companies and industries complete their work. Untrained end users risk facing unfunctional and nonuser- friendly Graphical User Interfaces. Recently, there has been shortages of people and talent in the heathcare industry where these applications would benefit in being used to accomplish easy and low level tasks. All these reasons contribute to the need of finding functional robot-user ways of communicating that allow the expansion of mobile manipulation applications. This thesis addresses the problem of finding an intuitive way to deploy a mobile manipulator in a laboratory environment. This thesis has analyzed whether it is possible to permit the user to work with a manipulator efficiently and without too much effort via a functional graphical user interface. Creating a modular interface based on user needs is the innovation value of this work. It allows the expansion of mobile manipulator applications that increases the number of possible users. To accomplish this purpose a Graphical User Interface application is proposed using an explanatory research strategy. First, user data was acquired using an ad hoc research survey and mixed with literature implementations to create the right application design. Then, an iterative implementation based on code-creation and tests was used to design a valuable solution. Finally, the results from an observational user study with non-roboticist programmers are presented. The results were validated with the help of 10 potential end users and a validation matrix. This demonstrated how the system is both functional and user-friendly for novices, but also expressive for experts. / Mobilmanipulatorer förändrar sättet som företag och industrier utför sitt arbete. Otränade slutanvändare och särskilt de utan programmeringskunskap kommer att bemötas av icke-funktionella och användarovänliga grafiska användargränssnitt. Den senaste tiden har det varit brist på specialiserad personal inom hälsovårdsindustrin som har resulterat i ett beroende på dessa applikationer för att genomföra enkla uppgifter samt uppgifter på låg nivå. Alla dessa faktorer bidrar till det ökande behovet att hitta ett funktionellt sätt att kommunicera mellan robot och slutanvändare vilket tillåter expansionen av mobilmanipulatorapplikationer. Arbetet som beskrivs i denna avhandling adresserar problemet att finna ett intuitivt sätt att använda en mobilmanipulator i ett laboratoriemijö. Möjligheten att tillåta användaren att på ett enkelt och effektivt sätt arbeta med en manipulator via ett funtionellt grafiskt användargränssnitt analyseras. Innovationsvärdet och detta examensarbetes bidrag till nuvarande kunskap betraktar möjligheten att skapa ett modulärt gränssnitt baserat på användares behov. Detta möjliggör expansionen av mobilmanipulatörers applikation vilket ökar antalet möjliga användare. En förklarande forskningsstrategi används för att föreslå en grafisk användargränssnittsapplikation för att uppnå detta mål. Först användes data från ad hoc-undersökningar blandat med litteraturimplementeringar för att skapa den rätta applikationsdesignen. En iterativ implementering baserad på kodskapande samt tester användes sedan för att designa en värdefull lösning redo att testas. Slutligen presenteras resultat från en användarobservationsstudie med icke-robotikprogrammerare. De insamlade resultaten som samlades in under valideringsstadiet tack vare en grupp bestående av tio potentiella slutanvändare har analyserats genom användandet av en valideringsmatris som är baserad på tre parametrar. Detta demonstrerade hur systemet är både funktionellt och användarvänligt för nybörjare men också expressivt för experter.
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Design and development of a graphical user interface for the monitoring process of an automated guided vehicle fleetPaul, Johanna January 2020 (has links)
Many different autonomously driving mobile robots are used for industrial transports of materials or oods in the context of internal logistic processes because of different use cases. The problem for the users that need to monitor the robots is that each manufacturer provides its own graphical user interface (GUI) wi th different operating modes and visual designs, which requires different trainings and constant swi tching between software. Therefore, this paper shows the design and development process of a graphical user interface in the form of a web application for the monitoring process of a fleet of automated guided vehicles from different manufacturers and answers the following question: "What are the main criteria when designing a graphical user interface with high usability for the monitoring process of manufacturer-independent automa ted guided vehicle f leets?” To answer the question, existing graphical user interfaces from different manufacturers were analyzed and interviews with developers and end-users of the GUIs were conducted. Requirements were then derived, on whose basis sketching, wireframing and high-fidelity prototyping have been performed. Usability testing and a heuristic evaluation were chosen to improve the application and its usability continually. As a result, the following six main criteria could be derived that summarize the most essential points to consider when designing such a GUI: administrabi lity, adaptiveness, observability, analyzability, robot and job awareness, and intervention. / Många olika autonomt körande mobila robotar används för industriell transport av material eller varor i samband med interna logistiska processer till följd av olika användningsfall. Problemet för de användare som behöver övervaka robotarna är att varje tillverkare tillhandahåller sitt eget grafiska användargränssnitt (GUI) med olika driftsätt och visuella utformningar, vilket kräver olika utbildningar och ständig växling mellan mjukvara. Denna uppsats visar därför design- och utvecklingsprocessen för ett grafiskt användargränssnitt i form av en webbapplikation för övervakningsprocessen för en samling av automatiserade guidade fordon från olika tillverkare, och svarar på följande fråga: "Vilka är de viktigaste kriterierna vid utformningen av ett grafiskt användargränssnitt med hög användbarhet för övervakningsprocessen av automatiserade guidade fordonsamlingar, oboeroande av tillverkare?” För att svara på frågan analyserades befintliga grafiska användargränssnitt från olika tillverkare, samt intervjuer med utvecklare och slutanvändare av GUI:erna utfördes. Krav härleddes sedan, baserat på vilka skisser, wireframing och hifi -prototyper som har utförts. Användbarhetstest och en heuristisk utvärdering valdes för att kontinuerligt förbättra applikationen och dess användbarhet. Som ett resultat kan följande sex huvudkriterier härledas, de sammanfattar de viktigaste punkterna att tänka på när man utformar ett sådant GUI: förmåga att administrera, anpassningsförmåga, observerbarhet, analyserbarhet, robot- och jobbmedvetenhet och intervention.
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Neurobiologically-based Control System for an Adaptively Walking HexapodLewinger, William Anthony 17 March 2011 (has links)
No description available.
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ON THE MUTUAL VISIBILITY OF FAT MOBILE ROBOTSAlsaedi, Rusul Jabbar 27 April 2016 (has links)
No description available.
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Dynamics and controls for an omnidirectional robotHenning, Timothy Paul January 2003 (has links)
No description available.
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[pt] MODELAGEM E CONTROLE CINEMÁTICO DE UM ROBÔ MÓVEL PARA NAVEGAÇÃO AUTÔNOMA EM CAMPOS AGRÍCOLAS / [en] MODELING AND KINEMATIC CONTROL OF A MOBILE ROBOT FOR AUTONOMOUS NAVIGATION IN AGRICULTURAL FIELDSADALBERTO IGOR DE SOUZA OLIVEIRA 25 February 2021 (has links)
[pt] Nos últimos anos, os robôs móveis têm emergido como uma solução alternativa
para o aumento do nível de automação e mecanização na agricultura.
Neste contexto, o foco da agricultura de precisão é a otimização do uso de
insumos, redução de perdas nas lavouras, redução do desperdício de água
e melhorar a produtividade em áreas cada vez menores, tornando a produção
mais eficiente e sustentável. Os robôs agrícolas, ou AgBots podem
ser controlados remotamente ou atuar de forma autônoma, utilizando diferentes
sistemas de locomoção, bem como serem equipados com atuadores
e sensores que lhes permitem realizar diversas tarefas agrícolas, tais como
plantio, colheita, poda, fenotipagem, monitoramento e coleta de dado, entre
outros. Neste trabalho será realizado um estudo em robôs móveis com
rodas direcionado para os modelos de tração diferencial e no modelo similar
ao carro (com atuação do sistema de direção) e suas aplicações em
navegação autônoma em ambientes agrícolas. A modelagem e o projeto de
controle baseiam-se em técnica clássicas e avançadas, utilizando abordagens
de controle robusto por modo deslisante, tanto de primeira como de segunda
ordens (Super Twisting Algorithm) para lidar com incertezas e interferências
externas, comumente encontradas no tipo de ambiente agrícola a que se
destina. Teste de verificação e validação são realizados através de simulações
numéricas (MATLAB) e em ambiente de virtualização 3D (Gazebo). Testes
experimentais preliminares são incluídos para ilustrarem as possibilidades
de aplicação das metodologias de controle propostas em um ambiente real.
Conclusões a respeito do trabalho são apresentadas, desenvolvendo uma discussão
sobre os seus pontos mais relevantes, bem como sobre as perspectivas
de melhorias futuras e pontos que ainda podem ser melhor pesquisados. / [en] In the last years, mobile robots have emerged as an alternative solution
for increasing the levels of automation and mechanization in agricultural
fields. In this context, the key idea of precision agriculture is to optimize
the use of production inputs, crop losses, waste of water and to increase
the crop production in small areas, in an efficient and sustainable manner.
Agricultural robots or AgBots may be autonomous or remotely controlled,
being endowed with different types of locomotion apparatus, actuation and
sensory systems, as well as specialized tools which enable them to carry out
a number of agricultural tasks such as, seeding, pruning, harvesting, phenotyping,
monitoring and data collection. In this work, we perform a study
on two type of wheeled mobile robots (i.e., differential-drive and car-like)
and their application for autonomous navigation in agricultural fields. The
modeling and control design is based on classical and advanced approaches,
using robust control approaches such as Sliding Mode Control (first order)
and Super Twisting Algorithm (second order) to deal with parametric uncertainties
and external disturbances, commonly founded in agricultural fields.
Verification and validation are carried out by means of numerical simulations
in MATLAB and 3D computer simulations in Gazebo. Preliminary
experimental tests are included to illustrate the performance and feasibility
of the proposed modeling and control methodologies. Concluding remarks
and perspectives are presented to summarize the strengths and weaknesses
of the proposed solution and to suggest the scope for future improvements.
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Structure and Gait Optimizationof a Soft Quadrupedal Robot / Struktur- och gångoptimeringav en mjuk fyrbent robotDanelia, David, Fu, Shuo January 2021 (has links)
Quadrupedal robots are mobile robots with four limbs. Compared with other mobile robots, quadrupedal robots are more capable of moving in complex environment. Specifically, softquadrupedal robots have the limbs that are flexible and more compliant with the environmentthan that of rigid quadrupedal robots. This project is based on a previous work at KTH where a soft quadrupedal robot prototype was built. The first part of this project is to build a test rig, analyze the dynamics of the 3D printed soft continuum actuators and choose one configuration toachieve the best dynamics. The second part of this project is to build a soft quadrupedal robotand analyze the standing and walking performance. The mechanical and electrical structure ofthe robot are re-designed to reduce the weight. Furthermore, gait analyses are conducted toenable the robot to walk. Cost of transport is calculated to compare the efficiency of differentgaits. / Mobila robotar som har fyra lemmar kallas fyrbenta robotar. Jämfört med andra mobila robotarär fyrbenta robotar mer kapabla att röra sig i komplexa miljöer. Särskild de mjuka fyrbentarobotar, vars flexibla lemmar är mer kompatibla med miljön än dem av stela fyrbenta robotar. Det här projektet är baserat på ett tidigare arbete på KTH där prototypen av en mjuk fyrbentrobot byggdes. Den första delen av detta projekt är att bygga en provrigg, analysera dynamikenav det 3D-skrivna mjuka kontinuumställdon och välja den konfigurationen som har bästadynamiken. Den andra delen av detta projekt är att bygga en mjuk fyrbent robot och analyseradess stå- och gångprestation. Den mekaniska och elektriska strukturen av roboten designades omför att minska vikten. Vidare är gångs analyser genomförda för att möjliggöra robotens gång. Cost of transport (COT) är uträknat för att jämföra olika gångs effektivitet.
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[en] EXPLORATION AND VISUAL MAPPING ALGORITHMS DEVELOPMENT FOR LOW COST MOBILE ROBOTS / [pt] DESENVOLVIMENTO DE ALGORITMOS DE EXPLORAÇÃO E MAPEAMENTO VISUAL PARA ROBÔS MÓVEIS DE BAIXO CUSTOFELIPE AUGUSTO WEILEMANN BELO 16 October 2006 (has links)
[pt] Ao mesmo tempo em que a autonomia de robôs pessoais e
domésticos
aumenta, cresce a necessidade de interação dos mesmos com
o ambiente. A
interação mais básica de um robô com o ambiente é feita
pela percepção deste e
sua navegação. Para uma série de aplicações não é prático
prover modelos
geométricos válidos do ambiente a um robô antes de seu
uso. O robô necessita,
então, criar estes modelos enquanto se movimenta e percebe
o meio em que está
inserido através de sensores. Ao mesmo tempo é necessário
minimizar a
complexidade requerida quanto a hardware e sensores
utilizados. No presente
trabalho, um algoritmo iterativo baseado em entropia é
proposto para planejar
uma estratégia de exploração visual, permitindo a
construção eficaz de um modelo
em grafo do ambiente. O algoritmo se baseia na
determinação da informação
presente em sub-regiões de uma imagem panorâmica 2-D da
localização atual do
robô obtida com uma câmera fixa sobre o mesmo. Utilizando
a métrica de
entropia baseada na Teoria da Informação de Shannon, o
algoritmo determina nós
potenciais para os quais deve se prosseguir a exploração.
Através de procedimento
de Visual Tracking, em conjunto com a técnica SIFT (Scale
Invariant Feature
Transform), o algoritmo auxilia a navegação do robô para
cada nó novo, onde o
processo é repetido. Um procedimento baseado em
transformações invariáveis a
determinadas variações espaciais (desenvolvidas a partir
de Fourier e Mellin) é
utilizado para auxiliar o processo de guiar o robô para
nós já conhecidos. Também
é proposto um método baseado na técnica SIFT. Os processos
relativos à obtenção
de imagens, avaliação, criação do grafo, e prosseguimento
dos passos citados
continua até que o robô tenha mapeado o ambiente com nível
pré-especificado de
detalhes. O conjunto de nós e imagens obtidos são
combinados de modo a se criar
um modelo em grafo do ambiente. Seguindo os caminhos, nó a
nó, um robô pode
navegar pelo ambiente já explorado. O método é
particularmente adequado para
ambientes planos. As componentes do algoritmo proposto
foram desenvolvidas e
testadas no presente trabalho. Resultados experimentais
mostrando a eficácia dos
métodos propostos são apresentados. / [en] As the autonomy of personal service robotic systems
increases so has their
need to interact with their environment. The most basic
interaction a robotic agent
may have with its environment is to sense and navigate
through it. For many
applications it is not usually practical to provide robots
in advance with valid
geometric models of their environment. The robot will need
to create these models
by moving around and sensing the environment, while
minimizing the complexity
of the required sensing hardware. This work proposes an
entropy-based iterative
algorithm to plan the robot´s visual exploration strategy,
enabling it to most
efficiently build a graph model of its environment. The
algorithm is based on
determining the information present in sub-regions of a 2-
D panoramic image of
the environment from the robot´s current location using a
single camera fixed on
the mobile robot. Using a metric based on Shannon s
information theory, the
algorithm determines potential locations of nodes from
which to further image the
environment. Using a Visual Tracking process based on SIFT
(Scale Invariant
Feature Transform), the algorithm helps navigate the robot
to each new node,
where the imaging process is repeated. An invariant
transform (based on Fourier
and Mellin) and tracking process is used to guide the
robot back to a previous
node. Also, an SIFT based method is proposed to accomplish
such task. This
imaging, evaluation, branching and retracing its steps
continues until the robot has
mapped the environment to a pre-specified level of detail.
The set of nodes and
the images taken at each node are combined into a graph to
model the
environment. By tracing its path from node to node, a
service robot can navigate
around its environment. This method is particularly well
suited for flat-floored
environments. The components of the proposed algorithm
were developed and
tested. Experimental results show the effectiveness of the
proposed methods.
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Fusão de informações obtidas a partir de múltiplas imagens visando à navegação autônoma de veículos inteligentes em abiente agrícola / Data fusion obtained from multiple images aiming the navigation of autonomous intelligent vehicles in agricultural environmentUtino, Vítor Manha 08 April 2015 (has links)
Este trabalho apresenta um sistema de auxilio à navegação autônoma para veículos terrestres com foco em ambientes estruturados em um cenário agrícola. É gerada a estimativa das posições dos obstáculos baseado na fusão das detecções provenientes do processamento dos dados de duas câmeras, uma estéreo e outra térmica. Foram desenvolvidos três módulos de detecção de obstáculos. O primeiro módulo utiliza imagens monoculares da câmera estéreo para detectar novidades no ambiente através da comparação do estado atual com o estado anterior. O segundo módulo utiliza a técnica Stixel para delimitar os obstáculos acima do plano do chão. Por fim, o terceiro módulo utiliza as imagens térmicas para encontrar assinaturas que evidenciem a presença de obstáculo. Os módulos de detecção são fundidos utilizando a Teoria de Dempster-Shafer que fornece a estimativa da presença de obstáculos no ambiente. Os experimentos foram executados em ambiente agrícola real. Foi executada a validação do sistema em cenários bem iluminados, com terreno irregular e com obstáculos diversos. O sistema apresentou um desempenho satisfatório tendo em vista a utilização de uma abordagem baseada em apenas três módulos de detecção com metodologias que não tem por objetivo priorizar a confirmação de obstáculos, mas sim a busca de novos obstáculos. Nesta dissertação são apresentados os principais componentes de um sistema de detecção de obstáculos e as etapas necessárias para a sua concepção, assim como resultados de experimentos com o uso de um veículo real. / This work presents a support system to the autonomous navigation for ground vehicles with focus on structured environments in an agricultural scenario. The estimated obstacle positions are generated based on the fusion of the detections from the processing of data from two cameras, one stereo and other thermal. Three modules obstacle detection have been developed. The first module uses monocular images of the stereo camera to detect novelties in the environment by comparing the current state with the previous state. The second module uses Stixel technique to delimit the obstacles above the ground plane. Finally, the third module uses thermal images to find signatures that reveal the presence of obstacle. The detection modules are fused using the Dempster-Shafer theory that provides an estimate of the presence of obstacles in the environment. The experiments were executed in real agricultural environment. System validation was performed in well-lit scenarios, with uneven terrain and different obstacles. The system showed satisfactory performance considering the use of an approach based on only three detection modules with methods that do not prioritize obstacle confirmation, but the search for new ones. This dissertation presents the main components of an obstacle detection system and the necessary steps for its design as well as results of experiments with the use of a real vehicle.
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