Master Degree / Yüksek Lisans Tezleri
Permanent URI for this collectionhttps://hdl.handle.net/11147/3008
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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 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 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.Master Thesis Augmented Reality-Based Model-Mediated Teleoperation: a Mobile Telerobot Case Study(Izmir Institute of Technology, 2019) Kirişci, Nihat Çağhan; Dede, Mehmet İsmet CanTeleoperation is defined as operating a robot in a remote environment. Teleoperation utilizes the strength and dexterity of robots and the interpretation and problem solving skills of humans. In a teleoperation system, the robot to be controlled is referred as the slave. The master is a device that the human operator interacts with to send commands to the slave or receive feedback from the slave environment such as haptic or audio. However, teleoperation of a robot in an unknown environment solely based on haptic and visual feedback is a demanding task. The effects of time delay in communication channels makes completing this task even more challenging. Model-Mediated Teleoperation (MMT) aims to solve this problem by creating a virtual model of the slave robot and the environment. This virtual model receives commands from the master and returns haptic feedback just as the real slave robot is interacting with the environment, effectively with no delay. However, without actually knowing where the position of the virtual robot corresponds in the real environment, it is still challenging to carry out the task. In this project, a novel augmented reality based method is proposed to render the virtual robot into the real life live video feed. Integration of the non-delayed robot into the real environment intends to solve this problem by enhancing the perception of the user.Master Thesis Analysis and Modeling of an Actuation System To Be Used in Light-Weight Collaborative Robots(Izmir Institute of Technology, 2019) Yılmaz, Mert; Dede, Mehmet İsmet CanCollaborative robots are a relatively new concept in robotics and industrial automation. Traditional industrial robots are relatively expensive, heavy, and dangerous devices for humans since they are enclosed in working cells with fences. Nowadays, in small and medium enterprises (SMEs), instead of traditional robots lightweight and versatile robots are required which can work alongside human co-workers. In such applications, human safety is a critical factor. ISO has produced new standards for these robots to regulate their collaborative work with human co-workers and named these robots as collaborative robots. The subject of the thesis is related to the actuation systems of light-weight collaborative robots. For these robots, a variety of actuation systems are designed in recent years which are usually modular and compact actuation systems. The main aim of the thesis is to analyze and model of a commonly used actuation system in collaborative robots and to verify its model.Master Thesis Compliance Control of Shad Redundant Robot(Izmir Institute of Technology, 2018) Kanık, Mert; Dede, Mehmet İsmet Can; Tatlıcıoğlu, EnverSHAD robot, which is located in IYTE Robotics Laboratory, is designed as a 4 degrees-of-freedom manipulator which has a PRRR serial kinematic structure. The prismatic joint works along the vertical axis, and the revolute joints rotate about the vertical axis. Although the positioning task on the plane can be executed by two revolute joints, SHAD robot is designed to be kinematically redundant using three revolute joints. SHAD name is the abbreviations for SHoulder Haptic Device. The manipulator is constructed by using industrial servomotors coupled with high reduction ratio gears. Hence, this robot can only be used as a haptic device if admittance control is implemented for its control scheme. Accordingly, the aim of this study is to implement and test the admittance control algorithm on SHAD robot. However, since a human operator uses this haptic device when he/she is placed inside the workspace, certain safety precautions should be implemented. Therefore, initially, exploiting the kinematic redundancy of SHAD robot, an obstacle avoidance algorithm to move the robot’s links away from the human operator is implemented and tested in simulations and experiments. To do this; (1) SHAD’s mathematical model is derived, (2) This model is verified, and obstacle avoidance algorithm is validated by simulation tests in MATLAB/Simulink, (3) SHAD robot’s experimental setup is developed, (4) Experimental tests for obstacle avoidance are conducted. After the obstacle avoidance algorithm is implemented in the control of SHAD and proven that it works, admittance control experiments are carried out on human subjects to investigate the effects of the admittance term parameters, mass and damper, on certain performance metrics of the user. It is deduced that; (1) as the mass parameter of the admittance term is increased, accuracy of the operation is decreased while the total effort of the user is increased, (2) as the damper parameter of the admittance term is increased, both the accuracy of the operation and the total effort of the user are increased, (3) when the same corner frequency with different admittance term parameters are used, the accuracy of the operation is almost the same but total effort increases as the parameters increase.Master Thesis Design and Development of a Continuously Variable Transmission System To Be Used in Human-Robot Interfaces(Izmir Institute of Technology, 2018) Mobedi, Emir; Dede, Mehmet İsmet CanContinuously Variable Transmission (CVT) systems are being used for many applications such as automotive transmissions, robotics, and aerospace. In an ideal condition, these systems have the potential to provide continuously varying power transmission within a predefined limit. This transmission is accomplished with the help of friction, belt or gear systems. CVT can find application in a human-robot interface if a set of design criteria including backdrivability, independent output position and stiffness variation, shock absorbing and low mass and inertia can be satisfied. Even if there are various CVT designs in the literature for human-robot interfaces, the primary limitation of the two-cone drive CVT designs is that the output torque and the output position cannot be altered independently. Considering the friction drive CVT designs, the reason for this problem is that the friction wheel, which is designed to transmit the torque from the input cone to the output cone, gives rise to remarkable longitudinal friction force along the linear way. In order to overcome this problem, a sphere is used in the work presented in this thesis 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 pre-tension in order to solve the bidirectional transmission problem. Additionally, an adjustment of the normal force applied on the cones is designed in order to regulate the shock absorption limitations.Master Thesis Design of a 2r1t Mechanism With Remote Center of Motion for Minimally Invasive Transnasal Surgery Applications(Izmir Institute of Technology, 2018) Yaşır, Abdullah; Kiper, Gökhan; Dede, Mehmet İsmet CanIn minimally invasive surgery, use of robotic manipulators is becoming more and more common in order to have more precise operations and better post-operative processes. Such operations are often performed through an incision port (a pivot point) on the patient’s body. Since the manipulator should move about the pivot point, it should have a remote center of motion. In this regard, the main objective of this thesis is designing a 3-dof (degrees-offreedom) surgical robotic arm that is capable of 2R1T (R: rotation, T: translation) motion pattern and is structured as a remote center of motion mechanism for minimally invasive surgery applications. First, the structural synthesis of a 3-dof manipulator with 2R1T motion pattern is performed. The synthesized structures also can be used for any kind of 2R1T-type applications. Then, the manipulators with various kinematic structures are evaluated for a transnasal surgery according to several evaluation criteria such as feasibility of construction for a remote center of motion mechanism, ease of balancing, number of links, structural symmetry, decoupling of the joint inputs and the output motion of the platform and the number of actuators connected to the base. The best option is evaluated as a parallel manipulator with two 1 F0-system and one 1 F0-1 F∞-system leg structures. Afterwards, kinematic analysis of the spatial parallel manipulator is formulated with a simplified kinematic model consisting of three intersecting planes so that dimensional design is done for a desired dexterous workspace. Finally, constructional design is completed and a prototype is manufactured and tested.
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