Mechanical Engineering / Makina Mühendisliği

Permanent URI for this collectionhttps://hdl.handle.net/11147/4129

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  • Conference Object
    Redundancy resolution options for the twin-it-romans robotic hybrid manufacturing system
    (Springer Science and Business Media B.V., 2025) Gündüz, G.M.; Dede, Mehmet İsmet Can; Kiper, Gökhan; Schmitz, M.; Corves, B.
    The Twinnig Iztech in Robotics Manufacturing System (TWIN-IT-ROMANS) project funded by EU Horizon -Widera-2023-Access-02-01 aims to develop a hybrid manufacturing system that can perform additive and subtractive manufacturing processes and inline quality control using a robotic system. The system will incorporate a 6-degree-of-freedom robot arm and a positioner with 2-degree-of-freedom, which will operate synchronously. This manipulation system is to be designed for performing different manufacturing operations with different degrees-of-freedom requirements. In order to reveal alternative trajectory planning scenarios for this system, this paper presents an initial review of redundancy resolution approaches for kinematically redundant robotic manipulators. First, the four main approaches for redundancy resolution techniques are introduced. Then main studies on energy minimization and stiffness maximization for kinematically redundant robotic manipulators are reviewed. Similar or new approaches are planned to be generated and implemented for the redundant system for hybrid manufacturing. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2025.
  • Conference Object
    Towards Sustainable Manufacturing: a Review and Future Directions in Additive Manufacturing of Fiber-Reinforced Polymer Composites
    (Springer Science and Business Media B.V., 2025) Türkcan, M.Y.; Tetik, Halil; Kurt, B.; Dede, Mehmet İsmet Can; Karaş, B.; Tetik, H.; Shokrani, A.; Dede, M.İ.C.
    The United Nations Sustainable Development Goals (SDGs) provide a global framework for addressing critical challenges such as climate change, resource scarcity and sustainable industrialization. With increasing demand for products and improving quality of life, linear consumption of materials and resources following the “take-make-waste” is no longer possible. As such, innovative solutions are increasingly necessary to enable circular economy in manufacturing. Additive manufacturing (AM) has emerged as a transformative technology in achieving SDGs by enhancing resource efficiency and minimizing waste. Fiber reinforced composites are a promising application of AM, as they offer the potential to optimize material use, reduce labor and support sustainable production practices. However, there is an urgent need for considering circular economy strategies, life cycle assessment (LCA) frameworks and effective recycling at the end of their lifetime. This study examines additive manufacturing systems for fiber-reinforced composites, their environmental impact and exploring the potential contributions of robotic integration in composite manufacturing to enhanced sustainability. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2025.
  • Conference Object
    Citation - Scopus: 3
    A Continuously Variable Transmission System Designed for Human–robot Interfaces
    (Springer, 2021) Mobedi, Emir; Dede, Mehmet İsmet Can
    Within a predefined limit, continuously variable transmission (CVT) systems can continuously vary the power transmission ratio. The transmission in CVTs is achieved via friction, belt or gear systems. If CVT designs can incorporate backdrivability, independent output position and impedance variation, shock absorbtion, and low mass and inertia, they can be employed in human–robot interfaces. Among various types of CVT designs, the two-cone drive CVT designs have a major drawback since the output torque and position cannot be changed independent of each other. The friction wheel used in this design does not have a holonomic motion capability and causes this inconvenience. In order to overcome this problem, a sphere is used in this work for the CVT design as the transmission element. In addition, it is stated in the literature that common CVT drive systems do not have the capability to be used in cyclic bidirectional motion. In the presented CVT design, a second sphere is added to the system with two springs from the lower part of the cones for pretension in order to solve the bidirectional transmission problem. In this paper, the working principle and conceptual design details of the novel two-cone CVT drive are presented. Experimental results showed that the novel CVT has the capacity to transmit bidirectional power with some accuracy. © 2021, Springer Nature Singapore Pte Ltd.
  • Book Part
    Citation - WoS: 1
    Citation - Scopus: 1
    A Historical Review of Polyhedral Linkages
    (Springer, 2024) Kiper, Gökhan
    Polyhedral linkages are linkages that resemble polyhedral shapes at different configurations. This paper summarizes the necessary geometrical fundamentals of polyhedral geometry and presents a historical and critical review of the polyhedral linkage designs available in the literature. Basic definitions of polyhedral geometry and operations are needed to comprehend and design polyhedral linkages. First, early works on polyhedral linkages are presented, where flexible polyhedra with rigid faces and flexible edges are issued. The final part is reserved to conformal polyhedral linkages, which go through shape transformations while plane, dihedral and solid angles are preserved. Conformal polyhedral linkages are examined in four categories: 1) Jitterbug-like linkages with screwing polygonal links connected to each other with dihedral angle preserving links, 2) polyhedral linkages with planar kinematic chains in radial motion planes, 3) polyhedral linkages with planar kinematic chains on faces, that are connected to each other with dihedral angle preserving links, and 4) other conformal polyhedral linkages. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2024.
  • Conference Object
    Energy and Exergy Analysis of a Roof-Mounted Photovoltaic System in Gebze-Turkey
    (Springer, 2024) Khalejan, Seyed Hamed Pour Rahmati; Cankurt, Tolga; Dede, Mehmet İsmet Can
    This study investigates the electrical and thermal exergy, power conversion efficiency and exergy efficiency of a roof-mounted photovoltaic (PV) system considering environmental parameters such as solar irradiation, ambient temperature and wind speed over a year. The values of solar exergy and solar potential are obtained by taking into account the solar insolation. Experimental and theoretical results indicate that wind speed and surface temperature have significant effects on the thermal exergy and exergy efficiency of solar PV systems. The mean solar potential in the region was found to be 93%. In addition, the electrical exergy was varied from 9145 W to 40460 W and the thermal exergy of PV systems was varied from 1639 W to 6193 W. While the range of PV power conversion efficiency varies from 6.15% to 11.56% over a year, the range of exergy efficiency varies from 5.31% to 9.78%. © 2024, The Author(s), under exclusive license to Springer Nature Switzerland AG.
  • Conference Object
    Citation - Scopus: 3
    Four-bar function generation using excel solver
    (Springer, 2023) Söylemez, Eres; Kiper, Gökhan
    The Chapter presents a simple and efficient way of approximating a function with a four-bar mechanism using four or five design parameters including one or both of the initial crank angles. The method only involves solution of linear set of equations and evaluating determinants, whereas nonlinear equations are numerically solved using a simple program such as Excel. So, the method is easy to explain and can be taught in an undergraduate course along with the wellknown linear three precision point synthesis problem. Precision point synthesis, order synthesis, mixed order synthesis, least squares approximation and extreme point synthesis can all be treated using the same method. The proposed method is illustrated with numerical examples for all mentioned synthesis problems and shown to be quite efficient with very low amount of structural error values.
  • Conference Object
    Citation - Scopus: 3
    Design and Balancing of a Novel 2r1t Manipulator With Remote Center of Motion
    (Springer, 2023) Yılmaz, Tuğrul; Kiper, Gökhan
    The paper presents a novel manipulator design to be used as an endoscope holder for endonasal skull base surgeries. The manipulator should provide two rotational and one translational motions for the endoscope, where it should be able to be oriented about and slide along the tip of the nostril of a patient as a pivot point. First, suitable manipulators with remote center motion are investigated. Manipulators with serial and hybrid kinematic structure and redundant manipulators with a passive joint are examined. A serial manipulator with a circular arc as the second rotation axis is chosen for the detailed design. The novelty of the kinematic structure of the manipulator is that the end-effector heave motion is achieved in a tangential direction to the circular arc. The constructional design and counter-mass balancing solution for the manipulator are presented. The total assembly mass is 11.6 kg for navigating an endoscope of 0.44 kg mass.
  • Conference Object
    Citation - WoS: 1
    Citation - Scopus: 1
    Modeling a Magneto-Rheological Fluid-Based Brake Via a Neural Network Method
    (Springer international Publishing Ag, 2022) Kucukoglu, Sefa Furkan; Dede, Mehmet Ismet Can; Ceccarelli, Marco
    Identifying the model of a magneto-rheological (MR) fluid-based brake is extremely important for designing and controlling a haptic device with hybrid actuation. Therefore, in this study, an Elman Recurrent Neural Network (ERNN) is designed to understand and model a characterization of an MR fluid-based rotational brake. Three important factors that affect the MR brake's performance are chosen as inputs: current, speed, and the first derivative of the input current. The proposed network is trained, and the performance of the network is tested with three different experimental scenarios. Then, the effect of these inputs on the system is investigated. According to the results, it can be said that the designed ERNN is a good candidate for modelling an MR brake.
  • Conference Object
    Citation - Scopus: 1
    Kinematic Representation of a Biomimetic Squid Soft Robot's Arms in a Simulation Environment
    (Springer international Publishing Ag, 2022) Emet, Hazal; Dede, M. I. Can
    Biomimetic robot systems have received attention from researchers and in accordance the implementation of soft robotic arms has been studied. Kinematic and dynamic modeling of robots with infinite degrees of freedom is challenging and a number of methods have been proposed. In this work, a procedure is proposed to represent soft robot arm motion in a simulation environment. A biomimetic squid robot is used as a case study. This robot's soft arms are modeled by using the Piecewise Constant Curvature approach. This model is visualized by discretizing the soft arms into a finite number of rigid-body manipulators in MatLab using its 3D animation toolbox.
  • Conference Object
    Asymmetry in the Tension and Compression Flow Stress and the Effect of Sub-Cell Size on the Hardness of a Selective Laser Melt 316l Stainless Steel
    (Springer, 2022) Güden, Mustafa; Enser, Samed; Arslan Hamat, Burcu; Tanrıkulu, A. Alptuğ; Yavaş, Hakan
    An asymmetry between tension and compression tests was determined experimentally in the Selective Laser Melt (SLM) stainless steel 316L alloy in the building direction. The asymmetry was ascribed to the used biaxial scanning strategy which resulted in a strong alignment of 〈110〉 along the build direction (fiber texture) and a random distribution of 〈100〉, 〈110〉 and 〈111〉 directions normal to the building direction. The strong fiber texture in the building direction induced lower twinning stress in tension than in compression, while the tension and compression twining stresses were found similar in the normal to building direction. The favored twinning in the specimens tested in the building direction resulted in a higher tensile true fracture strain; hence, a higher ductility. Lastly, the hardness measurements made on the specimens having similar gain sizes, but different sub-cell sizes processed using higher and lower laser powers tended to support that the sub-cell boundaries in SLM-316L alloy acted as imperfect barriers to the dislocation motion.