397 research outputs found

    Robots and tools for remodeling bone

    Get PDF
    The field of robotic surgery has progressed from small teams of researchers repurposing industrial robots, to a competitive and highly innovative subsection of the medical device industry. Surgical robots allow surgeons to perform tasks with greater ease, accuracy, or safety, and fall under one of four levels of autonomy; active, semi-active, passive, and remote manipulator. The increased accuracy afforded by surgical robots has allowed for cementless hip arthroplasty, improved postoperative alignment following knee arthroplasty, and reduced duration of intraoperative fluoroscopy among other benefits. Cutting of bone has historically used tools such as hand saws and drills, with other elaborate cutting tools now used routinely to remodel bone. Improvements in cutting accuracy and additional options for safety and monitoring during surgery give robotic surgeries some advantages over conventional techniques. This article aims to provide an overview of current robots and tools with a common target tissue of bone, proposes a new process for defining the level of autonomy for a surgical robot, and examines future directions in robotic surgery

    Study of the application of a collaborative robot for machining tasks

    Full text link
    [EN] The importance of collaborative robots is increasing very fast in the industry. They have several advantages over the 'classical' robot arms: they may work side-by-side with humans, their environment needs less adaptation, they may be easily transported, etc. Their joints are more elastic than those in classical robots. For this reason, they are less suited for machining. In this work, a collaborative robot, a sensor of 6 Degree of Freedom (DOF) and a spindle with flex-shaft attachment are used to perform milling operations on soft materials. An inner/outer loop control is being developed to control the movements and the cutting forces. The experiments have been designed to evaluate the capability of the robot with milling operations with different parameters. An analysis of the dimensions and the finished surface will be carried out. The contribution of this article is to determine the possibilities and limitations of the collaborative robots in machining applications, with external control of forces.The authors are grateful for the financial support of the Spanish Ministry of Economy and European Union, grant DPI2016-81002-R (AEI/FEDER, UE). This work was funded by the CONICYT PFCHA/DOCTORADO BECAS CHILE/2017 - 72180157Pérez-Ubeda, R.; Gutiérrez, SC.; Zotovic Stanisic, R.; Lluch-Cerezo, J. (2019). Study of the application of a collaborative robot for machining tasks. Procedia Manufacturing. 41:867-874. https://doi.org/10.1016/j.promfg.2019.10.009S86787441International Federation of Robotics, IFR forecast: 1.7 million new robots to transform the world´s factories by 2020, IFR. (2017). https://ifr.org/ifr-press-releases/news/ifr-forecast-1.7-million-new-robots-to-transform-the-worlds-factories-by-20 (accessed February 15, 2019).Robotic Industries Association (RIA), Top 6 Future Trends in Robotic Automation, RIA. (2018). https://www.robotics.org/blog-article.cfm/Top-6-Future-Trends-in-Robotic-Automation/101 (accessed May 6, 2019).A. Grau, M. Indri, L. Lo Bello, T. Sauter, Industrial robotics in factory automation: From the early stage to the Internet of Things, in: Proc. IECON 2017 - 43rd Annu. Conf. IEEE Ind. Electron. Soc., 2017: pp. 6159–6164. doi:10.1109/IECON.2017.8217070.Hui Zhang, Jianjun Wang, G. Zhang, Zhongxue Gan, Zengxi Pan, Hongliang Cui, Zhenqi Zhu, Machining with flexible manipulator: toward improving robotic machining performance, in: Proceedings, 2005 IEEE/ASME Int. Conf. Adv. Intell. Mechatronics., IEEE, 2005: pp. 1127–1132. doi:10.1109/AIM.2005.1511161.Klimchik, A., Ambiehl, A., Garnier, S., Furet, B., & Pashkevich, A. (2017). Efficiency evaluation of robots in machining applications using industrial performance measure. Robotics and Computer-Integrated Manufacturing, 48, 12-29. doi:10.1016/j.rcim.2016.12.005Iglesias, I., Sebastián, M. A., & Ares, J. E. (2015). Overview of the State of Robotic Machining: Current Situation and Future Potential. Procedia Engineering, 132, 911-917. doi:10.1016/j.proeng.2015.12.577U. Robots, An introduction to common collaborative robot applications, White Pap. (2018) 18. https://info.universal-robots.com/common-collaborative-robot-applications (accessed September 23, 2018).R. Perez, S.C. Gutierrez Rubert, R. Zotovic, A Study on Robot Arm Machining: Advance and Future Challenges, in: 29TH DAAAM Int. Symp. Intell. Manuf. Autom., 2018: pp. 0931–0940. doi:10.2507/29th.daaam.proceedings.134.Chen, S., & Zhang, T. (2018). Force control approaches research for robotic machining based on particle swarm optimization and adaptive iteration algorithms. Industrial Robot: An International Journal, 45(1), 141-151. doi:10.1108/ir-03-2017-0045B. Siciliano, Robotics: Modelling, Planning and Control (2nd edition), 2010. doi:10.1007/978-1-84628-642-1

    Propuesta de inclusión de esfuerzos en el control de un brazo robot para asegurar el cumplimiento de la rugosidad superficial durante operaciones de lijado en diferentes materiales

    Full text link
    Tesis por compendio[ES] El mecanizado con brazos robots ha sido estudiado aproximadamente desde los años 90, durante este tiempo se han llevado a cabo importantes avances y descubrimientos en cuanto a su campo de aplicación. En general, los robots manipuladores tienen muchos beneficios y ventajas al ser usados en operaciones de mecanizado, tales como, flexibilidad, gran área de trabajo y facilidad de programación, entre otras, frente a las Máquinas Herramientas de Control numérico (MHCN) que necesitan de una gran inversión para trabajar piezas muy grandes o incrementar sus grados de libertad. Como desventajas, frente a las MHCN, los brazos robóticos poseen menor rigidez, lo que combinado con las altas fuerzas producidas en los procesos de mecanizado hace que aparezcan errores de precisión, desviaciones en las trayectorias, vibraciones y, por consiguiente, una mala calidad en las piezas fabricadas. Entre los brazos robots, los brazos colaborativos están en auge debido a su programación intuitiva y a sus medidas de seguridad, que les permiten trabajar en el mismo espacio que los operadores sin que estos corran riesgos. Como desventaja añadida de los robots colaborativos se encuentra la mayor flexibilidad que estos tienen en sus articulaciones, debido a que incluyen reductores del tipo Harmonic drive. El uso de un control de fuerza en procesos de mecanizado con brazos robots permite controlar y corregir en tiempo real las desviaciones generadas por la flexibilidad en las articulaciones del robot. Utilizar este método de control es beneficioso en cualquier brazo robot; sin embargo, el control interno que incluyen los robots colaborativos presenta ventajas que permiten que el control de fuerza pueda ser aplicado de una manera más eficiente. En el presente trabajo se desarrolla una propuesta real para la inclusión del control de esfuerzos en el brazo robot, así como también, se evalúa y cuantifica la capacidad de los robots industriales y colaborativos en tareas de mecanizado. La propuesta plantea cómo mejorar la utilización de un control de fuerza por bucle interior/exterior aplicado en un brazo colaborativo cuando se desconocen los pares reales de los motores del robot, así como otros parámetros internos que los fabricantes no dan a conocer. Este bucle de control interior/exterior ha sido utilizado en aplicaciones de pulido y lijado sobre diferentes materiales. Los resultados indican que el robot colaborativo es factible para realizar tales operaciones de mecanizado. Sus mejores resultados se obtienen cuando se utiliza un bucle de control interno por velocidad y un bucle de control externo de fuerza con algoritmos, Proporcional-Integral-Derivativo o Proporcional más Pre-Alimentación de la Fuerza.[CA] El mecanitzat amb braços robots ha estat estudiat aproximadament des dels anys 90, durant aquest temps s'han dut a terme importants avanços i descobriments en el que fa al seu camp d'aplicació. En general, els robots manipuladors tenen molts beneficis i avantatges al ser usats en operacions de mecanitzat, com ara, flexibilitat, gran àrea de treball i facilitat de programació, entre d'altres, davant de Màquines Eines de Control Numèric (MECN) que necessiten d'una gran inversió per treballar peces molt grans o incrementar els seus graus de llibertat. Com a desavantatges, enfront de les MECN, els braços robòtics posseeixen menor rigidesa, el que combinat amb les altes forces produïdes en els processos de mecanitzat fa que apareguin errors de precisió, desviacions en les trajectòries, vibracions i, per tant, una mala qualitat en les peces fabricades. Entre els braços robots, els braços col·laboratius estan en auge a causa de la seva programació intuïtiva i a les seves mesures de seguretat, que els permeten treballar en el mateix espai que els operadors sense que aquests corrin riscos. Com desavantatge afegida als robots col·laboratius es troba la major flexibilitat que aquests tenen en les seves articulacions, a causa de que inclouen reductors del tipus Harmonic drive. L'ús d'un control de força en processos de mecanitzat amb braços robots permet controlar, i corregir, en temps real les desviacions generades per la flexibilitat en les articulacions del robot. Utilitzar aquest mètode de control és beneficiós en qualsevol braç robot, però, el control intern que inclouen els robots col·laboratius presenta avantatges que permeten que el control de força es puga aplicar d'una manera més eficient. En el present treball es desenvolupa una proposta real per a la inclusió del control d'esforços en el braç robot, així com s'avalua i quantifica la capacitat dels robots industrials i col·laboratius en tasques de mecanitzat. La proposta planteja com millorar la utilització d'un control de força per bucle interior/exterior aplicat en un braç col·laboratiu, quan es desconeixen els parells reals dels motors del robot, així com altres paràmetres interns que els fabricants no donen a conèixer. Aquest bucle de control interior/exterior ha estat utilitzat en aplicacions de polit sobre diferents materials. Els resultats indiquen que el robot col·laboratiu és factible de realitzar aquestes operacions de mecanitzat. Els seus millors resultats s'obtenen quan s'utilitza un bucle de control intern per velocitat i un bucle de control extern de força amb els algoritmes Proporcional-Integral-Derivatiu o Proporcional més Pre-alimentació de la Força.[EN] Machining with robot arms has been studied approximately since the 90s; during this time, important advances and discoveries have been made in its field of application. In general, manipulative robots have many benefits and advantages when they are used in machining operations, such as flexibility, large work area, and ease of programming, among others, compared to Numerical Control Machine Tools (NCMT) that need a great investment to work very large pieces or increase their degrees of freedom. As for disadvantages, compared to NCMT, robotic arms have lower rigidity, which, combined with the high forces produced in machining processes, causes precision errors, path deviations, vibrations, and, consequently, poor quality in the manufactured parts. Among robot arms, collaborative arms are on the rise due to their intuitive programming and safety measures, which allow them to work in the same space without risk for the operators. An added disadvantage of collaborative robots is their flexibility in their joints because they include Harmonic drive type reducers. The use of force control in machining processes with robot arms makes possible to control and correct, in real-time, the deviations generated by the flexibility in the robot's joints. The use of this control method is beneficial for any robot arm. However, the internal control included in collaborative robots has advantages that allow the force control to be applied more efficiently. In this work, a real proposal is developed to include effort control in the robot arm. The capacity of industrial and collaborative robots in machining tasks is evaluated and quantified. The proposal recommends how to improve the use of an inner/outer force control loop applied in a collaborative arm, when the real torques of the robot's motors are unknown and other internal parameters that manufacturers do not disclose. This inner/outer control loop has been used in polishing and sanding applications on different materials. The results indicate that the collaborative robot is feasible to perform such machining operations. Best results are obtained using an internal velocity control loop and external force control loop with Proportional-Integral-Derivative or Proportional plus Feed Forward.The authors are grateful for the financial support of the Spanish Ministry of Economy and European Union, grant DPI2016-81002-R (AEI/FEDER, UE). This work was funded by the CONICYT PFCHA/DOCTORADO BECAS CHILE/2017 – 72180157.Pérez Ubeda, RA. (2022). Propuesta de inclusión de esfuerzos en el control de un brazo robot para asegurar el cumplimiento de la rugosidad superficial durante operaciones de lijado en diferentes materiales [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/182000TESISCompendi

    Kinematic analysis of a novel 2-d.o.f. orientation device

    Get PDF
    This paper presents the development of a new parallel robot designed for helping with bone milling surgeries. The robot is a small modular wrist with 2 active degrees of freedom, and it is proposed to be used as an orientation device located at the end of a robotic arm designed for bone milling processes. A generic kinematic geometry is proposed for this device. This first article shows the developments on the workspace optimization and the analysis of the force field required to complete a reconstruction of the inferior jawbone. The singularities of the mechanism are analyzed, and the actuator selection is justified with the torque requirements and the study of the force space. The results obtained by the simulations allow building a first prototype using linear motors. Bone milling experiment video is shown as additional material

    Intraoperative tissue classification methods in orthopedic and neurological surgeries: A systematic review

    Full text link
    Accurate tissue differentiation during orthopedic and neurological surgeries is critical, given that such surgeries involve operations on or in the vicinity of vital neurovascular structures and erroneous surgical maneuvers can lead to surgical complications. By now, the number of emerging technologies tackling the problem of intraoperative tissue classification methods is increasing. Therefore, this systematic review paper intends to give a general overview of existing technologies. The review was done based on the PRISMA principle and two databases: PubMed and IEEE Xplore. The screening process resulted in 60 full-text papers. The general characteristics of the methodology from extracted papers included data processing pipeline, machine learning methods if applicable, types of tissues that can be identified with them, phantom used to conduct the experiment, and evaluation results. This paper can be useful in identifying the problems in the current status of the state-of-the-art intraoperative tissue classification methods and designing new enhanced techniques

    Characterization of a Contact-Stylus Surface Digitization Method Using Collaborative Robots: Accuracy Evaluation in the Context of Shoulder Replacement or Resurfacing

    Get PDF
    Total shoulder arthroplasty (TSA) is the third most common joint replacement. While robot-assisted hip and knee replacement technologies have enjoyed extensive development, this has been limited in the upper limb. This work focused on quantifying the localization accuracy of a robotic system, and evaluating its efficacy in the context of TSA. A collaborative robot was fitted with a stylus tip to perform manual surface digitizations using the robot’s encoder output. In the first experiment, two precision-machined master cubes, representing the working volume around a glenoid structure, were used for system validation. Next, cadaveric glenoids were digitized and compared to a ‘gold standard’ laser scanner. Digitization errors were 0.37±0.27 mm, showing that collaborative robotics can be used for osseous anatomy digitization. This thesis presents two novel concepts: 1) use of collaborative robotics for manually operated surface digitizing, and 2) optical fiducial technique, allowing registration between a laser scanner and stylus digitizer

    Robotizing the conventional and Hot-Forging Wire Arc Additive Manufacturing processes for producing 3D parts with complex geometries

    Get PDF
    Wire Arc Additive Manufacturing (WAAM) is an Additive Manufacturing (AM) process which has high deposition rates at reduced costs, being suitable to produce large size compo-nents. Hot-Forging WAAM (HF-WAAM) is a WAAM variant which uses an oscillating hammer to forge the material as it is deposited, improving mechanical properties and the microstruc-ture of the produced parts. This study aimed to use and validate the WAAM and HF-WAAM to robotize the pro-duction of compact metallic and complex geometry parts. Thus, a welding torch capable of performing forging was redesign, developed and assembled in a 6 degree-of-freedom (6-DoF) manipulator robot. 316LSi stainless steel parts were produced using WAAM and HF-WAAM processes. During their production, the vibration signal of the robot was acquired and then processed and compared. The AM robotic system demonstrated to be suitable to build these parts, since the tool tip speed and tool tip to substrate distance are controlled, and the tool path optimized. It was also observed that vibration did not negatively affect the built parts quality.O Wire Arc Additive Manufacturing (WAAM) é um processo de Manufatura Aditiva (MA) que apresenta elevadas taxas de deposição a custos reduzidos sendo adequado para produzir peças de grandes dimensões. O Hot-Forging WAAM (HF-WAAM) é uma variante do WAAM que usa um martelo oscilante para forjar o material à medida que este vai sendo depositado, melhorando as propriedades mecânicas e a microestrutura das peças produzidas. Este trabalho tem como objetivo usar e validar o WAAM e HF-WAAM para robotizar a produção de peças metálicas com geometria complexa. Para isto, uma tocha de soldadura com capacidade de realizar forjamento foi redesenhada, fabricada, e montada num robô manipu-lador de 6 graus de liberdade (6-DoF). Foram produzidas peças em aço inoxidável 316LSi uti-lizando os processos de WAAM e HF-WAAM. Durante a sua produção, o sinal de vibração do robô foi adquirido e posteriormente processado e comparado. O sistema robótico de MA demonstrou ser adequado para produzir peças quando a velocidade da ponta da ferramenta e a distância da ponta da ferramenta ao substrato estavam controladas e o percurso da ferramenta otimizado. Também se observou que a vibração não afetou negativamente a qualidade das peças produzidas

    Robots in machining

    Get PDF
    Robotic machining centers offer diverse advantages: large operation reach with large reorientation capability, and a low cost, to name a few. Many challenges have slowed down the adoption or sometimes inhibited the use of robots for machining tasks. This paper deals with the current usage and status of robots in machining, as well as the necessary modelling and identification for enabling optimization, process planning and process control. Recent research addressing deburring, milling, incremental forming, polishing or thin wall machining is presented. We discuss various processes in which robots need to deal with significant process forces while fulfilling their machining task
    • …
    corecore