Master Degree / Yüksek Lisans Tezleri
Permanent URI for this collectionhttps://hdl.handle.net/11147/3008
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Master Thesis Seri-Elastik-Eyleyicili Bir Ameliyat Robotunun Kontrolcü Tasarımı(2025) Özkurt, Batuhan; Dede, Mehmet İsmet CanMekanik esneklik özelliği sayesinde darbeye karşı dayanımı arttırabilen, enerjinin güvenli bir biçimde depolanıp salınmasına imkan tanıyan, stabil kuvvet kontrolünü destekleyen ve çevresel zararı düşüren seri elastik eyleyiciler, insan-robot etkileşimi uygulamalarında sıklıkla kullanılmaktadır. Fakat onu kendiliğinden güvenli kılan bu özellikleri aynı zamanda bazı durumlarda çevre için bir riske de dönüştürebilir. Özellikle, ani temas kaybı elastik elemanda depolanan enerjinin serbest kalmasına ve serbest salınımların uyarılmasına yol açabilir. Bu tezde hedef, temas kaybından dolayı oluşan salınımların hızla sönümlenmesi ve sistemin temas kaybından önceki konumuna tekrar edilebilir bir biçimde geri getirilmesidir. Bu amaçla, viskoz sürtünmeli, iki ataletli spiral yaylı model tek serbestlik dereceli bir deney düzeneğinde kurulmuş ve konum hatasına integral etkisi eklenmiş bir Doğrusal Kuadratik Düzenleyici denetleyiciyle kontrol edilmiştir. Temas kaybı senaryosu bir servo fren ile simüle edilmiştir. Deneyler ve simülasyonlar denetleyicinin performansını doğrulamaktadır. Simülasyonlar Doğrusal Kuadratik Düzenleyici ağırlık matris seçimindeki avantajları ve dezavantajları göstermekte, kurulan deney düzeneğinde farklı başlangıç yay sapmalarında gerçekleştirilen ani temas kaybı deneyleri ise önerilen denetleyicinin performansını karşılaştırmalı olarak incelemektedir. Sonuçlar model tabanlı bir denetleyicinin temas kaybı sonrasında tekrarlanabilir bir biçimde salınımları sönümleyip sistemi eski pozisyonuna geri götürebildiğini göstermektedir.Master Thesis Controller Design of the Gyrostabilizer That Is Used in Boats(01. Izmir Institute of Technology, 2024) Bozelli, Muhammed Rıza; Dede, Mehmet İsmet CanBu tez, deniz taşıtlarında istenmeyen yalpa hareketini sönümlemek için kullanılan jiroskopik sönümleyici sistemleri için kontrol yapılarının geliştirilmesini sunmaktadır. İki farklı kontrolör tipi incelenmiş ve karşılaştırılmıştır: (1) geminin hız ve konum bilgilerini kullanan geleneksel kontrol yöntemi ve (2) en iyi sonuçları veren tam geri beslemeli kontrolörler. Tasarlanan kontrol çalışmalarını test etmek amacıyla küçültülmüş bir jiroskopik sönümleyici tasarlanmıştır. Prototip sistem geminin tek serbestlik dereceli yalpa hareketini modelleyecek şekilde tasarlanmıştır. Sisteme eklenen elektrik motoru, deniz durumunun bir bozucu etki olarak modellenmesini ve uygulanmasını sağlamaktadır. Bu bozucu etki gemi modeli üzerinde jiroskopik sönümleyici kullanılarak giderilmeye çalışılmıştır. Kontrol sisteminin tasarımından önce sistemin kinematik ve dinamik hesaplamaları analitik olarak yapılmıştır. Bu analitik çözümler simülasyon dosyası ile karşılaştırılarak doğrulanmıştır. Analitik çözümlerin açık formlarında jiroskop ve gemi arasındaki ilişkiler net bir şekilde gözlemlenmektedir. Analitik çözümlerde doğrusal olmayan terimlerin etkisi küçük bulunduğundan denklemler basitleştirilerek doğrusal kontrol sistemleri tasarlanmıştır. Matematiksel hesaplamalar ve 3 boyutlu tasarımın ardından prototip sistemin üretimi tamamlanmıştır. Tasarlanan konum-hız (PV-PI) kontrol sistemi ve doğrusal karesel regülatör (LQR) tabanlı kontrol sistemleri bu prototip sistem üzerinde test edilmiştir. Testlerin sonuçları, iki kontrol sisteminin birbirlerine karşı net bir üstünlüğü olmamasına rağmen, LQR kontrol sisteminin daha az parametreye sahip olması, diğer gemi-jiroskop kombinasyonlarına daha kolay uygulanabileceğini göstermektedir.Master Thesis Implementation of a Real-Time Teleoperation System for the Control of a Robotic Squid(01. Izmir Institute of Technology, 2023) Cezayirli, Hasan; Dede, Mehmet İsmet CanTeleoperation is defined as the remote control of a robotic system from an operational environment. Teleoperation of soft robots has been a growing research topic in recent years and there are still areas awaiting further studies. In this study, a real-time teleoperation system has been implemented for a robotic squid with four soft arms, to be used in underwater operations. The teleoperation system consists of dissimilar master-slave system kinematics, with multiple master systems and multiple slave systems. An operator utilizes two haptic devices for the manipulation of the four soft robot arms. Haptic feedback is incorporated into the system for ease of use. The slave system within the implemented teleoperation system is simulated using hardware-in-the-loop simulation. For this purpose, communication protocols from the real system are employed. In other words, the applied teleoperation system is integrated within the hardware-in-the-loop simulation of the real system. Experiments were conducted to validate that the implemented system is a real-time system and to evaluate the ease of use of the system from the operator's perspective. Additionally, experiments were expanded to measure the impact of haptic feedback on the performance of the operator. The experimental results indicate that the system is a real-time system and haptic feedback improves the system's ease of use.Master Thesis Design of a Physical Human-Robot Interface for Lifting Operations(Izmir Institute of Technology, 2022) Nalbant, Uğur; Dede, Mehmet İsmet Can; Dede, Mehmet İsmet CanIn this thesis, the design of a physical human-robot interface for lifting operations which controls the vertical movement of the payload is studied. The new design uses a low stiffness type of admittance control method that is aimed at reducing the surface impact force of the payload and providing better control for the operator while having the option of high stiffness admittance control. To reduce impact forces by using low stiffness admittance control, a sliding handle mechanism is introduced into the system. This type of design includes springs and bearings to create a low stiffness admittance-type user interface. Mathematical models are developed to calculate spring forces and mechanical strength. According to design requirements and mathematical calculations, the prototype is designed and manufactured. In the tests, it is seen that the spring forces are low, and the sliding motion of the handle is not consistent over different displacements. According to the test results, revisions are done, and the final design of the system is developed. In the final tests, it is seen that the new design of the physical human-robot interface performance is improved and the problem of the sliding motion of the handle is solved. Also, the surface impact forces are reduced with low stiffness admittance control. Another improvement of the new design is the ability to control the payload with high stiffness admittance control if the user chooses it. With this option, users can control the payload by touching the payload. Having both types of control methods, the user can choose which type of control method to use to handle payload in the factory.Master Thesis Design of an Actuation System for a Haptic Glove(Izmir Institute of Technology, 2022) Kurt, Kaan Erol; Dede, Mehmet İsmet CanIn this thesis, the design of a magneto-rheological fluid-based brake (MR brake) system that is aimed to be used on a conceptually designed force feedback virtual reality glove is presented. The reasons of MR brakes are assigned for this task is that they can provide high torque output in smaller volumes/masses, their ability to operate with low power requirements and their safe natures. During their designs, in addition to ensuring their usability for a haptic glove application, solutions have been presented and applied for the sticky wall and high off-state torque problems observed in the MR brake systems. In addition to these, a novel study has been carried out to overcome the low torque-to-mass ratio problem observed in drum-type MR brake architectures used for applications requiring small sizes due to their high manufacturability. The design starts with the determination of the requirements. Later, the mathematical models were developed to estimate the output torques to be obtained from the MR brake and the solid models of the parts were created respectively. In order to estimate the performance of the developed system, magneto-static finite element analyses (FEA) were carried out. The models were updated in line with the analysis results and, the production phase was started after all the design criteria are met. A prototype MR brake system was produced, assembled and tested in order to experimentally verify the analysis results. In the tests carried out, it was observed that all the determined design criteria were met and the developed MR brake system was found to be suitable to be used in a haptic glove application. Based on the test results, the off-state torque seen in MR brake systems, which can increase up to 25% of the maximum output torque, has been reduced to 3% of the total torque output and found to be 23 mN.m. Additionally, thanks to the improved drum-type design, the typical torque-to-mass ratio seen in drum-type MR brake architectures is increased from 1.4 N.m/kg to 2. 90 N.m/kg within 206 grams of mass and 597 mN.m of dynamic torque range of the developed system.Master Thesis Teleoperation of a Biomimetic Squid Robot's Arms Via Multiple Haptic Interfaces(01. Izmir Institute of Technology, 2022) Emet, Hazal; Dede, Mehmet İsmet CanBiomimetic robot systems have captured the attention of researchers for the past two decades. Along with biomimetic systems, the implementation of soft robotic arms has emerged and studied. Teleoperation of such biomimetic soft robots, i.e., a biomimetic squid robot, is still an open area of research. This study aims to initiate the development of a teleoperation system, which has multi-master multi-slave with dissimilar master-slave kinematics, to be adapted for the operation of an underwater biomimetic squid robot. The communication between the slave robot, which is the biomimetic squid robot’s soft arms, and the master system on the ground is estimated to have limited bandwidth. To overcome this problem, the model-mediation technique is selected to be adapted. The abstract information received from the slave side is used for regenerating the slave environment on the master side. The human operator uses two haptic devices to manipulate the four soft arms of this biomimetic robot via interacting with this regenerated model on the master side. The models of the biomimetic robot’s soft arms are developed by using the constant-curvature approach. While this study is limited in the sense that the slave side regeneration is previously completed on an ideally received signal even before the teleoperation is initiated, the teleoperation of 4 soft arms with two haptic devices is investigated. 4 different control strategies are formulated and evaluated on test subjects. The performances of the test subjects are evaluated based on their task completion duration, accuracy, and feedback received from their questionnaire answers. The primary investigation conducted is for the ergonomic use of teleoperation systems. Another evaluation is carried out to understand the influence of haptic feedback in telepresence. The evaluation results clearly indicate that the haptic feedback has improved the telepresence. The position-to-position mapping produced shorter task completion durations with worse accuracy relative to the position-to-velocity mapping.Master Thesis Enhancement of Trajectory Following Accuracy of High Acceleration Robots by Using Their Stiffness Properties(01. Izmir Institute of Technology, 2021) Paksoy, Erkan; Dede, Mehmet İsmet Can; Paksoy, Erkan; Dede, Mehmet İsmet CanIn recent years, there has been a push for the incorporation of robots into manufacturing processes. In general, parallel robots are preferred for processes requiring high repeatability and positioning accuracy. If the positioning accuracy of the end-effector of a robot has high priority, compliance characteristics of the elements of its mechanism should be considered. Due to the high accelerations or external loading on the robot, the dimensions of the elements change and this leads to positioning errors for the end-effector. This thesis describes an experimental test setup and an experimental procedure for determining the compliance characteristics of planar mechanisms, followed by a comparison of the repeatability and stiffness performance of a parallel and an over-constrained mechanism. Finally, assumptions and methodology for using this compliance information to improve the trajectory tracking accuracy of high-accelerated robots are given. Portable coordinate measurement machine and calibrated weights are used to collect compliance information. The compliance behavior of the mechanisms defined for entire workspace by using the least squares and bilinear interpolation techniques. The D'Alambert principle is used to estimate fictitious forces that cause the compliance of the mechanism's end-effector while the mechanism operates at up to 5 g accelerations. As a result of this thesis, it is demonstrated that the mechanism's center of gravity and joint types play an important role in the mechanism's trajectory tracking accuracy, and that tracking accuracy can be improved by a simple data-driven compliance prediction algorithm.Master Thesis Gravity Compensation of a 2r1t Mechanism With Remote Center of Motion for Minimally Invasive Transnasal Surgery Applications [master Thesis](01. Izmir Institute of Technology, 2021) Aldanmaz, Ataol Behram; Artem, Hatice Seçil; Dede, Mehmet İsmet Can; Artem, Hatice Seçil; Dede, Mehmet İsmet CanIn this work, gravity balancing of a 2URRR-URR parallel manipulator is issued. The manipulator is designed as an endoscope holder for minimally invasive transnasal pituitary gland surgery application. In the surgery, the endoscope is placed through the nostril of the patient where there is a natural path to the pituitary gland. In case of a motor failure, in order to protect the patient and to ease the control of the manipulator static balancing for this manipulator is worked out, the manipulator prototype is balanced and tested. The parallel manipulator has three legs. The payload mass has been distributed to side legs due to workspace limitations. By using counter-mass for two links in each leg, the center of mass of each leg has been reduced to the proximal link which simplified the balancing problem to balancing of a two degree-of-freedom inverted pendulum. By connecting a zero free length spring to the proximal link the total mass of the leg the manipulator has been kept in static balance in its desired workspace. Simulations show that with the applied design, torque effects on the motors have been reduced by 93.5%. Finally, the balancing solution is applied on the manipulator with active motors and the manipulator has been balanced, the torque values mostly has been decreased where the joint clearance, spring tension adjustments and mechanical constraints has affected the results. With the elimination of the joint clearance, mechanical constraints and rearranging the spring tension the required torque could be minimized.Master Thesis Surgery Simulator Design for Minimally Invasive Pituitary Gland Surgery(01. Izmir Institute of Technology, 2021) Büyüköztekin, Tarık; Dede, Mehmet İsmet CanToday, interest in robotics applications in the medical field has increased as well as in every field of the industry due to the development in robotic technology and control. The use of robots in surgeries has become widespread. Researchers in Izmir Institute of Technology and Hacettepe University have produced a surgical assistance robot named NeuRoboScope for minimal invasive pituitary gland tumor surgeries. This robot handles and directs the endoscope during the surgery by receiving motion demands from the surgeon via a master system that is composed of a wearable ring and a foot pedal This thesis study aims to develop a simulator to train the surgeons for using the NeuRoboScope system. For this purpose, NeuRoboScope Surgery Simulator v2 (NSSv2) has been developed in which it is aimed to simulate operation conditions as well as the ideal conditions for NeuRoboScope education. To simulate the operation conditions, surgical instruments, endoscope and NeuRoboScope system controlling this endoscope are included in the simulator replicating the process of minimally invasive pituitary gland tumor surgery. NSSv2 system uses 2 haptic devices, a specially designed control ring that controls the active part of the NeuRoboScope system and has an inertial measurement unit and also wirelessly communicates with the system, a foot pedal activating the control of the ring, a model skull to determine the surgery region and a monitor that receives the visual feedback of the simulation to control the surgical instruments from the physical environment. In addition to training, it is aimed to customize the NeuRo boScope's teleoperation system with respect to user needs and operation styles. In line with this objective, the user calibration mode is generated. In this way, an efficient and customized control system is created for the use of the NeuRoboScope system. A training procedure is developed with several scenarios within the NSSv2 system. When users carry out this training, the completion time of the scenario, the number of pedal usage, and the amount of motion of the surgical tools are recorded by the system. Improvements in the capabilities of users can be observed and the efficiency of NSSv2 can be evaluated owing to these data.Master Thesis Design and Experimental Evaluation of a Dynamically Balanced Over-Constrained Planar 6r Parallel Manipulator(Izmir Institute of Technology, 2019) Özkahya, Merve; Kiper, Gökhan; Dede, Mehmet İsmet CanWith the development of the industry, the number of robots used in the production line is increasing day by day. Particularly, it is known that parallel robots are better in terms of positioning accuracy compared to serial robots based on the stretching of robot arms. In parallel mechanisms, there are many factors such as calibration, stability and dynamic balancing of the mechanism affecting positioning accuracy. The aim of this thesis is to dynamically balancing parallel mechanisms to improve positioning accuracy. In high acceleration applications, the shaking force and moment are the factors that cause vibration in the base of the mechanism. These vibrations can be reduced by designing dynamically balanced mechanisms. In this thesis, over- and simply constrained 6R mechanisms are designed for dynamic balancing studies and prototypes are produced. The counter mass method was used to balance the mechanism dynamically. The design of the masses was made according to the mass information received from the model designed in the computer aided drawing program and the parts of the mechanisms were updated according to their actual mass values after they were produced. The design of the masses is designed according to the mass information from CAD model and the parts of the mechanisms are updated according to their actual mass values after they are produced. Dimensional measurements were taken by FARO Prime Arm device due to faults that may arise from the production in the parts of the mechanism after production. Then the mechanism was assembled. Before carrying out the balancing tests, calibration studies affecting the positioning accuracy of the over-constrained mechanism were carried out. Finally, the mechanism is activated balanced and unbalanced and the acceleration effect of the 6-axis accelerometer is obtained experimentally.