Mechanical Engineeringhttp://hdl.handle.net/10679/462024-03-29T07:28:31Z2024-03-29T07:28:31ZDevelopment and 3D spatial calibration of a parallel robot for percutaneous needle procedures with 2D ultrasound guidanceAhmad, Mirza AwaisOrhan, Sabri OrçunYıldırım, Mehmet CanBebek, Özkanhttp://hdl.handle.net/10679/93192024-03-26T05:23:41Z2017-12-01T00:00:00ZDevelopment and 3D spatial calibration of a parallel robot for percutaneous needle procedures with 2D ultrasound guidance
Ahmad, Mirza Awais; Orhan, Sabri Orçun; Yıldırım, Mehmet Can; Bebek, Özkan
Robotic systems are being applied to medical interventions as they increase the operational accuracy. The proposed autonomous and ultrasound guided 5-DOF parallel robot can achieve such accuracy for needle biopsies, which particularly demand precise needle positioning and insertion. In this paper, the robot's mechanical design, system identifications, and the design of its controller are explained. A torque computed controller with gravity compensation and friction models, yielding a 0.678mm RMS position error for the needle tip, was used. A novel method was used for 3D space calibration of the images for detecting the volume of interest in the biopsy procedure by a multipoint crosswire phantom with parallel threads. The calibration technique had a validation RMS error of 0.03mm.
2017-12-01T00:00:00ZAn integrated design approach for a series elastic actuator: Stiffness formulation, fatigue analysis, thermal managementYıldırım, Mehmet CanŞendur, PolatBilgin, OnurGülek, BerkYapıcı, Güney GüvenUğurlu, Regaip Barkanhttp://hdl.handle.net/10679/93182024-03-26T04:55:39Z2017-12-22T00:00:00ZAn integrated design approach for a series elastic actuator: Stiffness formulation, fatigue analysis, thermal management
Yıldırım, Mehmet Can; Şendur, Polat; Bilgin, Onur; Gülek, Berk; Yapıcı, Güney Güven; Uğurlu, Regaip Barkan
This paper presents an integrated mechanical design approach for the long-Term and repetitive use of series elastic actuators (SEAs). Already, computational models for series elastic actuator design have been developed in order to address the challenging weight and volume targets. However, an integrated design method in which the coupling effects between various interacting requirements that are explored at every stage of the design cycle does not exist. In particular, the interactions between the torsional stiffness, strength, fatigue life and thermal performance are not analyzed in-depth. To this end, we propose a comprehensive design approach in which the aforementioned requirements (FEA, stiffness formulation, fatigue analysis, and thermal management) are integrated in a complementary manner. Computer-Aided analyses and experimental results verified the effectiveness of our design approach. The proposed approach is employed to manufacture our SEA module CoEx-SEA.
2017-12-22T00:00:00ZFree simulation software and libraryUğurlu, Regaip BarkanIvaldi, S.http://hdl.handle.net/10679/93072024-03-22T08:50:59Z2018-01-01T00:00:00ZFree simulation software and library
Uğurlu, Regaip Barkan; Ivaldi, S.
With the advent of powerful computation technologies and efficient algorithms, simulators became an important tool in most engineering areas. The field of humanoid robotics is no exception; there have been numerous simulation tools developed over the last two decades to foster research and development activities. With this in mind, this chapter is written to introduce and discuss the current-day open-source simulators that are actively used in the field. Using a developer-based feedback, we provide an outline regarding the specific features and capabilities of the open-source simulators, with a special emphasis on how they correspond to recent research trends in humanoid robotics. The discussion is centered around the contemporary requirements in humanoid simulation technologies with regard to the future of the field.
2018-01-01T00:00:00ZFlow visualization and LES simulations inside a chevron type plate heat exchangerPeçenek, ErdemErtunç, ÖzgürSenkal, C.http://hdl.handle.net/10679/93062024-03-22T08:15:50Z2018-01-01T00:00:00ZFlow visualization and LES simulations inside a chevron type plate heat exchanger
Peçenek, Erdem; Ertunç, Özgür; Senkal, C.
An up-scaled model of a single channel of CPHE was used under dynamically similar conditions for the experiments. In experiments, pressure drop measurements and flow visualizations were conducted with aluminum flitter and dye. For the numerical study, large eddy simulations are preferred in the turbulent regime which has the best fit with experiments. Also mixing inside the channel is analyzed and reported through numerical simulations. Results of this study exhibit flow structures differ from previous visualization studies with corrugated channels. The numerical results exhibit that LES estimates friction factor at high Reynolds numbers with maximum 5% error. Numerical visualizations are close the experimental visualizations in the study. Lastly mixing study exhibits that there is asymmetric mixing inside the channel.
2018-01-01T00:00:00Z