Person: ÜNAL, Ramazan
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Ramazan
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ÜNAL
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Conference ObjectPublication Metadata only Topology optimization-based design and development of a compact actuator with a high torque-to-weight ratio for quadrupeds(IEEE, 2022) Akın, Barış; Özçınar, Erim Can; Balcı, Barış; Emre, Sinan; Şendur, Polat; Bebek, Özkan; Ünal, Ramazan; Uğurlu, Regaip Barkan; Mechanical Engineering; ŞENDUR, Polat; BEBEK, Özkan; ÜNAL, Ramazan; UĞURLU, Regaip BarkanThis paper presents the design, development, and testing procedures for a compact actuator with a high torque-to-weight ratio, generally aimed to actuate legged robots, e.g., quadrupeds. The main goal of designing the actuator was to keep its total weight minimum while ensuring a high torque output. Therefore, the following design steps were implemented: i) the actuator was designed in accordance with the torque output requirement and the stress distribution that was mapped on actuator frames, ii) topology optimization was conducted on the initial design and it is modified in accordance with optimization results, and iii) the optima actuator design was built and tested on in a realistic scenario in which it powered an actual quadruped robot for validation. As the result, the proposed actuators could track the desired walking trajectory with a relatively low error. In conclusion, continuous torque output of 48 Nm was obtained via a lightweight (1.6-1.7 kg) actuator design.Conference ObjectPublication Open Access Discussing modernizing engineering education through the Erasmus + Project Titled "Open Educational Resources on Enabling Technologies in Wearable and Collaborative Robotics (WeCoRD)(Ege University) Kılıç-Bebek, Ebru; Nizamis, K.; Karapars, Gülhis Zeynep; Gökkurt, Muharrem Ali; Ünal, Ramazan; Bebek, Özkan; Vlutters, M.; Vander Poorten, E.; Borghesan, G.; Decré, W.; Aertbelien, E.; Borisova, O.; Borisov, I.; Kolyubin, S.; Kodal, M. I.; Uğurlu, Regaip Barkan; Industrial Design; Sectoral Education and Professional Development; Mechanical Engineering; BEBEK, Ebru Kılıç; KARAPARS, Gülhis Zeynep; GÖKKURT, Muharrem Ali; ÜNAL, Ramazan; BEBEK, Özkan; UĞURLU, Regaip BarkanThe Erasmus + project titled “Open Educational Resources on Enabling Technologies in Wearable and Collaborative Robotics (WeCoRD)", can serve as a model to establish strategic international and multidisciplinary partnerships to modernize engineering education. WeCoRD project is a collaboration among internationally renowned institutions from Turkey, Belgium, Russia, and the Netherlands to create an innovative course on wearable and collaborative robotics with Open Educational Resources (OERs) and an online Virtual Lab aimed at accessibility across Europe. This collaboration involves many fields from engineering, health, and design disciplines as well as an industry partner from the automotive manufacturing sector. The main objectives of the project are to: (1) prepare a graduate-level course in wearable and collaborative robotics, (2) enhance EU higher education capacity in the field with clear use-case scenarios from the industry and medical applications, (3) provide open-source materials including a virtual lab, and (4) fill the skill gap between the industry and the academia while also aiming a continued professional development. With these goals which aim to modernize engineering education and make it more relevant to the industry, the WeCoRD project brings both multidisciplinary and interdisciplinary aspects of robotics education to a new level. Each intellectual output (IO) of the project is allocated to a project partner based on their expertise. The course module design and development is planned as follows: The IO1 (the first course module) on “Components for wearable and collaborative robots” is led by Ozyegin University, Turkey; the IO2 (the second course module) on “Modeling, design and control or wearable and collaborative robots as systems” is led by ITMO, Russia; the IO3 (the third course module) on “Human-robot interaction for wearable and collaborative robots” is led by KU Leuven, Belgium; the IO4 (the fourth course module) on “Medical applications” is led by U.Twente; the IO5 (integration of the first three course modules into one course) on the graduate-level course to be integrated into graduate degree programs and to be adopted for continued professional development (CPD) training programs, as well as the translation of the course materials into Turkish is led by KU Leuven, Belgium; the IO6 on the “Virtual Lab” is led by ITMO, Russia; and finally IO7 on the “Video Collection” is led by Ozyegin University, Turkey. FORD-Otosan, which is one of the industry partners from Turkey will host students, provide site visits and offer workshops. Each project partner and their contributions will be addressing the fundamental need for modernizing engineering education through students’ active participation and boosting students’ skill development. In addition to multidisciplinary and interdisciplinary exposure, students will get a chance to work with industry partners and learn through authentic problem solving and relevant feedback. Providing a deeper and more effective learning experience will be among the core design principles of the course modules, labs, videos, and industry collaborations.Conference ObjectPublication Metadata only HandMECH—Mechanical hand prosthesis: Conceptual design of the hand compartment(Springer, 2022) Baysal, Barış; Ünal, Ramazan; Mechanical Engineering; ÜNAL, Ramazan; Baysal, BarışIn this study, conceptual design of the hand compartment of a body-powered hand prosthesis, HandMECH, is presented. HandMECH is a body-powered prosthesis and the hand compartment is designed according to human finger size and range of motion (RoM). Moreover, the design is governed by the daily activities performed by hand. In this regard, three types of grasp that are mostly used are identified. The thumb is designed with three degrees of freedom (DoF), i.e., translation and rotation, the index finger with three rotational DoF, and the other three fingers that generally move together are designed as combined and having one rotational DoF. In order to give the human finger flexibility, the fingers are designed to be made of flexible material and the other parts are of ABS material with the consideration of 3D printer for prototyping. CAD model is presented as an outcome of this study.ArticlePublication Metadata only Conceptual design of a fully passive transfemoral prosthesis to facilitate energy-efficient gait(IEEE, 2018-12) Ünal, Ramazan; Behrens, S.; Carloni, R.; Hekman, E.; Stramigioli, S.; Koopman, B.; Mechanical Engineering; ÜNAL, RamazanIn this paper, we present the working principle and conceptual design toward the realization of a fully-passive transfemoral prosthesis that mimics the energetics of the natural human gait. The fundamental property of the conceptual design consists of realizing an energetic coupling between the knee and ankle joints of the mechanism. Simulation results show that the power flow of the working principle is comparable with that in human gait and a considerable amount of energy is delivered to the ankle joint for the push-off generation. An initial prototype in half scale is realized to validate the working principle. The construction of the prototype is explained together with the test setup that has been built for the evaluation. Finally, experimental results of the prosthesis prototype during walking on a treadmill show the validity of the working principle.Conference ObjectPublication Open Access A soft+rigid hybrid exoskeleton concept in scissors-pendulum mode: A suit for human state sensing and an exoskeleton for assistance(IEEE, 2019-06) Uğurlu, Regaip Barkan; Acer, M.; Barkana, D. E.; Gocek, I.; Kucukyilmaz, A.; Arslan, Y. Z.; Basturk, H.; Samur, E.; Ugur, E.; Ünal, Ramazan; Bebek, Özkan; Mechanical Engineering; UĞURLU, Regaip Barkan; ÜNAL, Ramazan; BEBEK, ÖzkanIn this paper, we present a novel concept that can enable the human aware control of exoskeletons through the integration of a soft suit and a robotic exoskeleton. Unlike the state-of-the-art exoskeleton controllers which mostly rely on lumped human-robot models, the proposed concept makes use of the independent state measurements concerning the human user and the robot. The ability to observe the human state independently is the key factor in this approach. In order to realize such a system from the hardware point of view, we propose a system integration frame that combines a soft suit for human state measurement and a rigid exoskeleton for human assistance. We identify the technological requirements that are necessary for the realization of such a system with a particular emphasis on soft suit integration. We also propose a template model, named scissor pendulum, that may encapsulate the dominant dynamics of the human-robot combined model to synthesize a controller for human state regulation. A series of simulation experiments were conducted to check the controller performance. As a result, satisfactory human state regulation was attained, adequately confirming that the proposed system could potentially improve exoskeleton-aided applications.Conference ObjectPublication Metadata only HandMECH—Mechanical hand prosthesis: Conceptual design of a two degrees-of-freedom compliant wrist(Springer, 2022) Elsayed, Ahmed Abdelrahman Ibrahim; Ünal, Ramazan; Mechanical Engineering; ÜNAL, Ramazan; Elsayed, Ahmed Abdelrahman IbrahimA compliant wrist joint is important for positioning the hand in different positions to perform various daily tasks. It is also important that the wrist is able to achieve sufficient range of motion (RoM). The RoM is determined by classifying the daily activities and the most critical applications. This study presents kinematical, structural and kinetic analyses of the conceptual design of a wrist joint in mechanical hand prosthesis: HandMECH. Kinematic and kinetic analyses are carried out to determine the design parameters of the wrist to handle daily activities. Structural analyses is performed to evaluate the stress distributed over the critical part of the wrist and show that the design with a mass of 50 g satisfies the applied boundary condition.Conference ObjectPublication Metadata only Simulation-based design and locomotion control implementation for a lower body exoskeleton(IEEE, 2022) Derman, Mustafa; Soliman, Ahmed Fahmy; Kuru, Alihan; Çevik, Süleyman Can; Ünal, Ramazan; Bebek, Özkan; Uğurlu, Regaip Barkan; Mechanical Engineering; ÜNAL, Ramazan; BEBEK, Özkan; UĞURLU, Regaip Barkan; Derman, Mustafa; Soliman, Ahmed Fahmy; Kuru, Alihan; Çevik, Süleyman CanThis paper proposes a simulation-based design and locomotion control methodology for an exoskeleton that is aimed at providing assistance to users with ambulatory difficulties. To increase the power-to-weight ratio while satisfying design constraints, we made use of simulation tools to recursively update the initial mechanical design for a finer solution. To this end, a coupled human-exoskeleton model was constructed in MSC ADAMS environment using an average human model and the initial design of the robot. Following this step, dynamic walking control simulations were carried out to determine actuator torques and loading. Using the loading data obtained via simulation experiments, certain mechanical links were optimized such that the portions with no stress concentration were removed without violating safety. Finally, two distinct control implementations were conducted: i) stand-to-sit motion, ii) dynamic walking. As a result, we obtained dynamically consistent motion behavior for both cases, adequately validating the proposed methodology.Conference ObjectPublication Metadata only A custom brace design to connect a user limb to an exoskeleton link with minimal discomfort(IEEE, 2021) Çevik, Süleyman Can; Derman, Mustafa; Ünal, Ramazan; Uğurlu, Regaip Barkan; Bebek, Özkan; Mechanical Engineering; ÜNAL, Ramazan; UĞURLU, Regaip Barkan; BEBEK, Özkan; Çevik, Süleyman Can; Derman, MustafaExoskeletons are increasingly helping people with different applications. Regardless of what they were built for, exoskeletons have a common discomfort problem from the misalignment of robot and human joints. In this paper, a fixation design for a lower extremity exoskeleton is presented. A method was proposed to determine necessary passive degrees of freedom of the designed brace system and to identify the parameters affecting interaction forces and moments between human and exoskeleton. The proposed method was validated by analyzing the human-machine interface statically and dynamically. The results show that the problem of undesired interaction forces due to misalignment may be solved theoretically with the proposed design.Book PartPublication Metadata only Design of bio-joint shaped knee exoskeleton assisting for walking and sit-to-stance(Springer Nature, 2019) Kapci, M. F.; Ünal, Ramazan; Mechanical Engineering; ÜNAL, RamazanIn this study, a bio-joint shaped knee joint exoskeleton is presented. This design is meant for avoiding misalignment of the exoskeleton joint with the biological knee joint. For this purpose a cam mechanism has been designed to prevent the misalignment from translation of the femur on tibia. Additionally, walking and sit-to-stance is passively assisted with a spring element that is activated with the heel contact. A single spring is used for both walking and sit-to-stance, due to the similar characteristics of the gait cycle and initial phases of the sit-to-stance in joint stiffness.ArticlePublication Metadata only Transdisciplinarity as a learning challenge: Student experiences and outcomes in an innovative course on wearable and collaborative robotics(IEEE, 2023-06) Kılıç-Bebek, Ebru; Nizamis, K.; Vlutters, M.; Bebek, Özkan; Karapars, Gülhis Zeynep; Ünal, Ramazan; Yılmaz, Deniz; Uğurlu, Regaip Barkan; Industrial Design; Sectoral Education and Professional Development; Mechanical Engineering; Mitchell, J.; BEBEK, Ebru Kılıç; KARAPARS, Gülhis Zeynep; BEBEK, Özkan; ÜNAL, Ramazan; UĞURLU, Regaip Barkan; Yılmaz, DenizContribution: This study provides evidence for the benefit of short online courses for transdisciplinary competence development of graduate students. It shows the significant challenges students face while learning, and provides instructional recommendations to improve students’ learning quality and professionalism. Background: Developing wearable and collaborative robots requires industry collaboration and transdisciplinary competence. Industry’s involvement in long-term programs is becoming infeasible, and the nature of transdisciplinary learning has not been explored to inform instructional practices. Intended Outcomes: This study aimed to provide instructional recommendations based on an in-depth examination of a diverse group of graduate students’ learning and teamwork experiences as well as outcomes in a 5-day online transdisciplinary course. Application Design: 31 graduate students of engineering, industrial design, and health fields from 4 countries participated in online mixed-discipline instructional sessions and teams to address a real industry challenge. A mixed-methods approach was used to examine students’ experiences and learning outcomes based on a competence measure, session participation data, student journal entries, team progress reports, team elaboration visuals, and final team presentations. Findings: Students’ knowledge of industrial design, medical considerations, ethics and standards, effective teamwork, and self-regulated learning were increased. Students’ high motivation helped them deal with the challenges involved. Daily student journals, team reports, and visual elaboration tools were found to be beneficial for determining the challenges and learning quality. The observed student progress within 5 days is promising, making it worthwhile to further explore the benefits of short online courses for increasing graduates’ readiness and establishing university-industry collaborations in education.