243 research outputs found

    Design of an Anthropomorphic, Compliant, and Lightweight Dual Arm for Aerial Manipulation

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    This paper presents an anthropomorphic, compliant and lightweight dual arm manipulator designed and developed for aerial manipulation applications with multi-rotor platforms. Each arm provides four degrees of freedom in a human-like kinematic configuration for end effector positioning: shoulder pitch, roll and yaw, and elbow pitch. The dual arm, weighting 1.3 kg in total, employs smart servo actuators and a customized and carefully designed aluminum frame structure manufactured by laser cut. The proposed design reduces the manufacturing cost as no computer numerical control machined part is used. Mechanical joint compliance is provided in all the joints, introducing a compact spring-lever transmission mechanism between the servo shaft and the links, integrating a potentiometer for measuring the deflection of the joints. The servo actuators are partially or fully isolated against impacts and overloads thanks to the ange bearings attached to the frame structure that support the rotation of the links and the deflection of the joints. This simple mechanism increases the robustness of the arms and safety in the physical interactions between the aerial robot and the environment. The developed manipulator has been validated through different experiments in fixed base test-bench and in outdoor flight tests.Unión Europea H2020-ICT-2014- 644271Ministerio de Economía y Competitividad DPI2015-71524-RMinisterio de Economía y Competitividad DPI2017-89790-

    Design and control of a loader mechanism for the NMBU agricultural robot

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    Despite the development of new technologies, manual labour still continuous to play a large role within most modern agricultural operations, especially during harvest. Consequently, there is an increasing demand for new machines to reduce labour as a mean to limit costs, while increasing efficiency in a sustainable manner. This thesis concern itself with the design of a mechanism and control system for a robot arm that can substitute workers in logistical operations during strawberry harvest. More specifically, by lifting berry crates onto a robot platform and transporting them from the fields and to the packaging facilities. The robot arm is to be mounted on the platform composing a vehicle- manipulator system. As this thesis is connected to a general research project on agricultural robotics at the Norwegian University of Life Sciences, the chosen platform is the associated field robot Thorvald II. The thesis is divided into two parts, where Part I concerns the mechanical design of the robot arm, while Part II propose a system for controlling the mechanism. The design development process has involved assessments of available solutions before selecting components on the basis of controllability, mechanical properties and costs. The process of selection in Part II is however, based on finding solutions that are compatible with the robot platform’s network (Controller Area Network) and operating system (Robotic Operating System). Part I: Design and Mechanics The design of the robot arm presented in this thesis begun with a preliminary feasibility study conducted by Bjurbeck in September 2016. Following the assessment of this study, the robot arm is designed to have two degrees of freedom operating in the xz-plane. When mounted on the platform, the arm will be free to operate in a 3-dimensional space, as the platform moves in x and y-direction, and rotates around the z-axis. The arm is assembled from two parallel link pairs made from rectangular aluminium tubes, and a revolute and prismatic joint. Both joints are actuated by LinAk LA36 linear electric actuators. The end effector of the arm is a gripper head designed to grasp the handles of the strawberry crate. The gripper head is self-aligning with the crate’s orientation in order to reduce the precision of control needed to envelop and grasp the crate. The frame of the gripper head is made from aluminium angle profiles and sheet metal. A worm drive DC motor actuate the gripper claws via a double link mechanism. Part II: Modeling and Control The geometry of the design presented in Part I is modelled mathematically and the inverse kinematics solved analytically. The kinematics will be used in future implementation of a position control system. Two RoboteQ SDC2160 dual-channel controllers are chosen to control all four actuator mo- tors. The linear actuators are controlled in closed loop position tracking mode with absolute feedback. The gripper motor is controlled in open loop mode with end stop switches detecting the position of the claws. Experiments was conducted to match the controllers with the actuator motors. The experiments revealed firmware issues with the controller. The experiments also affirmed the controller need a script to operate the actuators efficiently. The thesis provides the foundations to build a prototype and write an operating script to test the mechanical design and control system.Til tross for den stadige utviklingen av ny teknologi spiller manuelt arbeid fortsatt en stor rolle i moderne landbruk, særlig i innhøsting. På grunn av den store arbeidkraften som trengs er det en stadig større etterspørsel etter nye maskiner som kan redusere behovet for manuelt arbeid for å redusere utgifter og effektivisere gårdsbruk på en bærekraftig måte. Denne masteroppgaven omhandler det mekaniske designet og reguleringssystemet til en robotarm laget for å kunne erstatte arbeidere i oppgaver tilknyttet logistikk ved innhøsting av jordbær. Dette gjøres ved at armen løfter kasser med bær opp på en robotplattform som transporterer kassene fra jordet og til et pakkeri. Robotarmen er da montert oppå plattformen. Siden oppgaven er tilknyttet et forskningsprosjekt i landbruksrobotikk ved Norges miljø- og biovitenskapelige universitet, var det naturlig å velge den universitetets robot Thorvald II som plattform.submittedVersionM-MP

    The 31st Aerospace Mechanisms Symposium

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    The proceedings of the 31st Aerospace Mechanisms Symposium are reported. Topics covered include: robotics, deployment mechanisms, bearings, actuators, scanners, boom and antenna release, and test equipment. A major focus is the reporting of problems and solutions associated with the development and flight certification of new mechanisms

    Sailbot 2017-2018

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    The goal of this MQP was to build and program a robot capable of competing in the 2018 International Robotic Sailing Competition (IRSC), also known as Sailbot. This project utilized existing research on control and design of autonomous sailboats, and built on lessons learned from the last two years of WPIÂs Sailbot entries. The final product of this MQP was a more reliable, easier to control, and more innovative design than last yearÂs event-winning boat

    Desenvolvimento de um veículo inovador para armazéns automáticos

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    Intralogistics is increasingly a matter of research and development as a form of optimization, automation, integration and management of the flow of materials and information that circulate within a business unit. With a strong connection to material handling equipment and automation solutions, intralogistics has proved to be one of the main factors responsible for something that is already happening: a fourth industrial revolution where it is possible to convert warehouses and manufacturing units into intelligent environments where the entire process can be controlled and supervised through a single system. It became necessary to develop more and more innovative and efficient solutions to the constant diversity of challenges proposed by the market. In this sense, it was proposed to develop something innovative within the area of Automated Storage and Retrieval Systems (AS/RS), a technology increasingly sought after by today's manufacturing plants. As such, the goal was to improve the most emergent AS/RS in recent years: the Pallet/Box Shuttle AS/RS. In order to achieve the proposed objective, it was necessary to analyze all the existing solutions in the market and, principally, to find the main points to be improved and the direction to follow in order to innovate an already advanced solution. The results show a robotized solution where it was possible to increase the automation of the operations in the storage systems and improve the responsiveness of the system, taking this solution to a new level.A intralogística é cada vez mais uma área de investigação e desenvolvimento como uma forma de otimização, automação, integração e gestão do fluxo de materiais e informações que circulam dentro de uma unidade de negócios. Com uma forte ligação com equipamentos de manipulação de materiais e soluções de automação, a intralogística provou ser um dos principais fatores responsáveis por algo que já está a acontecer: uma quarta revolução industrial, onde é possível converter armazéns e unidades fabris em ambientes inteligentes, onde todo o processo pode ser controlado e supervisionado através de um único sistema. Tornou-se necessário desenvolver soluções cada vez mais inovadoras e eficientes para a constante diversidade de desafios propostos pelo mercado. Nesse sentido, propôs-se desenvolver algo inovador dentro da área dos Armazéns Automáticos, uma solução cada vez mais procurada pelas unidades fabris de hoje. Como tal, estabeleceu-se o objetivo de melhorar o tipo de Armazém Automático mais emergente dos últimos anos: o Armazém Automático com Veículos Satélite para Caixas ou Paletes. Para alcançar o objetivo proposto, foi necessário analisar todas as soluções existentes no mercado e, principalmente, encontrar os principais pontos a serem aprimorados e definir a direção a seguir para se inovar uma solução já avançada. Os resultados obtidos apresentam uma solução robotizada onde foi possível aumentar a automatização das operações dos sistemas de armazenamento e melhorar a capacidade de resposta do sistema, levando esta solução para um novo patamar

    Sailbot 2017-2018

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    The goal of this MQP was to build and program a robot capable of competing in the 2018 International Robotic Sailing Competition (IRSC), also known as Sailbot. This project utilized existing research on control and design of autonomous sailboats, and built on lessons learned from the last two years of WPIs Sailbot entries. The final product of this MQP was a more reliable, easier to control, and more innovative design than last years event-winning boat
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