Mechanical Engineering / Makina Mühendisliği
Permanent URI for this collectionhttps://hdl.handle.net/11147/4129
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Conference Object Mechanisms, Transmissions and Applications(Springer, 2018) Dede, Mehmet İsmet Can; İtik, Mehmet; Lovasz, Erwin-Christian; Kiper, GökhanThis volume contains the proceedings of MeTrApp 2017, the 4th Conference on Mechanisms, Transmissions and Applications, that was held in Trabzon, Turkey, July 3-5, 2017. The topics treated in this volume are Mechanism Design, Parallel Manipulators, Control Applications, Mechanical Transmissions, Cam Mechanisms, and Dynamics of Machinery. The conference was organised by the IFToMM Technical Committees for “Linkages and Mechanical Controls” and “Gearing and Transmissions” under the patronage of the IFToMM and sponsorship of Karadeniz Technical University, Izmir Institute of Technology and IFToMM Turkey (MAKTED). The aim of the conference was to bring together researchers, scientists, industry experts and students to provide, in a friendly and stimulating environment, the opportunity to exchange know-how and promote collaboration in the field of Mechanism and Machine Science.Article Citation - WoS: 8Citation - Scopus: 8Pore Connectivity Effects on the Internal Surface Electric Charge of Mesoporous Silica(Springer, 2019) Şen, Tümcan; Barışık, MuratNano-scale confinements within mesoporous systems develop overlapping electric double layers (EDL) such that the existing theoretical models cannot predict the electric potential distributions and resulting surface charges. In addition, ionic conditions undergo local variation through connections between the pore voids and pore throats. For the first time in literature, we studied the charging behavior of mesoporous silica in terms of the pore to throat size ratio (R-pt) to characterize the pore connectivity effects, in addition to porosity (epsilon) and pore size (H). Both local and average surface charge densities inside mesoporous silica were examined by varying these parameters systematically. Results showed that the magnitude of surface charge density decreased with increasing EDL overlap and decreasing connectivity effects. We formulized this behavior and developed an extended model to predict mesoporous silica's internal charge as a function of porosity, pore size, and pore to throat size ratio.Article Citation - WoS: 14Citation - Scopus: 15Electrochemical Performance of La0.6sr0.4co0.2fe0.8o3-Ce0.9gd0.1o2 Composite Sofc Cathodes Fabricated by Electrocatalyst And/Or Electrocatalyst-Ionic Conductor Infiltration(Springer, 2019) Sındıraç, Can; Büyükaksoy, Aligül; Akkurt, SedatInfiltration of electrocatalyst precursor solutions into previously sintered porous ionic conductor scaffolds has been used recently as an alternative method to the conventional co-sintering route to fabricate electrocatalyst-ionic conductor composites for solid oxide fuel cell (SOFC) cathode applications. However, the aqueous nitrate solutions generally used to perform the infiltration process results in electrocatalyst precipitates that are disconnected from each other, yielding poor electrode performance. In this work, polymeric electrocatalyst (La0.6Sr0.4Co0.2Fe0.8O3-LSCF) precursors that produce interconnected thin films upon heat treatment were used to infiltrate porous ionic conductor Ce0.9Gd0.1O2-delta (GDC) scaffolds to overcome these issues. In addition, for the first time in the literature, a mixture of LSCF and GDC polymeric precursors, which would yield LSCF-GDC nanocomposite coatings on the grains of the porous GDC scaffold were used as the infiltration solution. Thus, further enhancement of the electrocatalyst/ionic conductor interfacial area and achievement of improved electrode performance was aimed. As a result of the optimization studies, the lowest measured area specific polarization resistance (ASR(cathode)) values of 0.47 and 0.73 omega.cm(2) were obtained for polymeric LSCF+GDC and LSCF precursor infiltrations respectively at 700 degrees C, in air. In addition, LSCF+GDC infiltration yielded electrodes with much improved long-term stability in comparison to those obtained by LSCF infiltration. [GRAPHICS] .Conference Object Internship Experience for Learning the Operation of a Cable-Driven Robot for Rehabilitation Tasks(Springer, 2019) Carbone, G.; Cafolla, D.; Ceccarelli, M.; Aydınoğlu, Öndercan; Demirel, MuratThis paper describes an example of internship experience at LARM, Laboratory of Robotics and Mechatronics, at University of Cassino and South Latium. In particular, the main focus of this paper is the learning process as basis of a proper internship. Namely, a specific experiential learning approach is proposed as referring to a low-cost servo motor operation task. The learning task is further defined and developed as referring to a real application with a cable-driven robot for rehabilitation tasks, which has been designed and built at LARM in Cassino and under further investigation within Agewell project.Book Part Citation - Scopus: 2Improved Usability of a Low-Cost 5-Dof Haptic Device for Robotic Teleoperation(Springer, 2019) Ateş, Gizem; Brunetti, Luca; Bonfè, MarcelloThe paper describes the design and application of a low-cost haptic device with five degrees of freedom (5-DOF), all of which are fully actuated for force/torque haptic display. The device is realized using two Novint Falcons, commercially available haptic devices with only translational DOF. The paper focus on the practical issues related to the use of such a haptic device as a robotic teleoperation master and provides solutions to improve its usability during an application inspired by surgical robotics, namely the teleoperated insertion of a needle into a soft tissue. Experiments demonstrate the usefulness of force feedback and virtual fixtures on both translation and orientation degrees of freedom. © 2019, CISM International Centre for Mechanical Sciences.Book Part Citation - Scopus: 2Computation Time Efficient Stiffness Analysis of the Modified R-Cube Mechanism(Springer, 2019) Görgülü, İbrahimcan; Dede, Mehmet İsmet CanParallel manipulators are known to be more stiff than the serial manipulators. However, modeling the stiffness for parallel manipulators are difficult compared to serial manipulators due to the constrained structure and passive joints. In addition, computation of the stiffness model for parallel manipulators are exhausting since it requires an iterative solution algorithm due requirement of force-position convergence of all serial chains connecting to the same mobile platform. Direct solutions are faster however, they lack in accuracy. In this study, direct solution is preferred for real-time application and analytic stiffness model of the modified R-CUBE mechanism is obtained by using Virtual Joint Method (VJM). The finite element (FE) model is constructed and simulated to validate the analytical model. Then, a combination of external wrenches $$\pm 5$$ N in various directions are applied on the mobile platform in both FE and VJM in some critical poses. Finally, the computed numerical results are listed and compared along with their computation times. © Springer Nature Switzerland AG 2019Conference Object Conceptual Design of a 2-Dof Planar High-Speed Industrial Parallel Manipulator(Springer, 2019) Uzunoğlu, Emre; Özkahya, Merve; Paksoy, Erkan; Taner, Barış; Dede, Mehmet İsmet Can; Kiper, GökhanThis study focuses on conceptual design alternatives for a planar high-speed/high-precision manipulator in terms of mechanism structure, control strate-gy, and drive system selection. These concepts are investigated specifically for planar 5-bar based parallel linkages. An over-constrained 6-bar linkage with par-allelogram loops and its simply constrained version are selected for detailed de-sign. In addition, a model-based control strategy including a stiffness model is discussed for future studies. Alternative drive systems are evaluated. Finally a prototype is presented.Book Part Citation - Scopus: 5An Experimental Test Procedure for Validation of Stiffness Model: a Case Study for R-Cube Parallel Mechanism(Springer, 2019) Görgülü, İbrahimcan; Dede, Mehmet İsmet Can; Carbone, GiuseppeHaptic device manipulators are used for generating haptic feedback. This feedback is composed of force which is regulated with respect to motion information. Accurate generation of the feedback requires exact position acquisition of the end-effector. Due to the compliant bodies of a manipulator, a stiffness model is needed to predict this position. Previously, Virtual Joint Method was adopted to obtain the stiffness model of an R-CUBE parallel haptic mechanism. In this paper, experimental test setup and experimental procedure are described for validating this stiffness model, its engineering feasibility and soundness of the proposed model.Book Part Citation - WoS: 1Citation - Scopus: 2Experimental Evaluation of Actuation and Sensing Capabilities of a Haptic Device(Springer, 2019) Mobedi, Emir; Görgülü, İbrahimcan; Dede, Mehmet İsmet CanHaptic devices are used to increase the telepresence level by providing the sense of touch to the human operator. Simultaneously, they capture the targeted motion of the human operator to generate a motion demand for the teleoperated slave system. Considering a scenario where the slave system’s end-effector is handled by the human operator at the master side, which is attached to the haptic device, an ideal haptic interaction involves the feeling of only the end-effector dynamics and the accurate sensation of the end-effector pose. The performance of a haptic device is based on these two functionalities. In this paper, the experimental evaluation of the actuation and sensing capabilities of a haptic device, HIPHAD v1.0 kinesthetic haptic device, is presented.Book Part Citation - WoS: 3Citation - Scopus: 5Design of a Teleoperation Scheme With a Wearable Master for Minimally Invasive Surgery(Springer, 2019) Ateş, Gizem; Majani, Ronny; Dede, Mehmet İsmet CanMinimally invasive surgery is increasingly being preferred over conventional surgery, however many problems still persist in longer surgeries such as pituitary surgeries, where surgeons are still required to hold an endoscope in their hand for prolonged periods of time. Many modern approaches have recently been proposed in literature to reduce the surgeon’s effort. In this paper we extended upon these previous attempts and presented a promising solution; a real time teleoperation scheme with 3 different modes of operation, composed of a wearable ring system that captures and transmits voluntary hand motions over a wireless connection to a slave system. Accordingly, this slave system processes the received data to generate velocity demands for the robot endoscope controller. Finally, the feasibility of the proposed modes of operation are demonstrated and compared by measuring their learning curve and effort by running a set of training simulations on human subjects.
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