Master Degree / Yüksek Lisans Tezleri

Permanent URI for this collectionhttps://hdl.handle.net/11147/3008

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Access Right: Open AccessSubject: search.filters.subject.Haptic devices

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Now showing 1 - 7 of 7
  • 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 Can
    Teleoperation 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 Can
    In 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 Can
    Biomimetic 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
    Development of Mr-Fluid Based Semi-Active Dampers To Be Used in Haptic Devices
    (Izmir Institute of Technology, 2017) Karabulut, Mehmet Görkem; Dede, Mehmet İsmet Can
    In this thesis, development of a novel Magneto-Rheological (MR) fluid based brake system is described which is designated to be used in kinesthetic haptic devices. The new design of MR-brake system consists of two identical directional brakes and with this feature, it presents a solution to the stiction problem that occurs when the MR-brake is activated which constrains the rotational motion in both direction. This constraint of the motion results in developing a feeling that the user is stuck in the virtual wall. By using two independently controlled brakes in a system, the rotational brake direction is controlled and thus the motion of the handle is constrained in one direction while the user is free to move the handle in the reverse direction. MR-brake is developed from a conceptual design to the final design by applying a design optimization method. This method incorporates the use of Finite Element Analysis (FEA) and mathematical model of the system. Using this method, it is possible to predict the performance of the design to check if it meets the requirements that are specified by considering the future use of the device. After manufacturing a prototype, its performance is experimentally validated in a test rig which is also constructed in the scope of this thesis study. Experimental study includes two sections as characterization and frequency response test. As a result, the prototype is characterized with constructing the torquecurrent relation, which clearly shows the expected hysteresis in operation. The control model of the system is mathematically modeled with %95 accuracy ratio using the obtained experimental results. Experimental results show that the maximum brake torque of the system is 3.84 Nm and the minimum torque value is 0.15 Nm. The frequency response of the system is experimentally investigated and using this result, the system’s transfer function is estimated and its bode diagram is drawn. According to this result, the bandwidth of the system is calculated to be 63 rad/s.
  • Master Thesis
    Design of a Six Degree-Of Haptic Hybrid Platform Manipultor
    (Izmir Institute of Technology, 2010) Bilgincan, Tunç; Dede, Mehmet İsmet Can
    The word Haptic, based on an ancient Greek word called haptios, means related with touch. As an area of robotics, haptics technology provides the sense of touch for robotic applications that involve interaction with human operator and the environment. The sense of touch accompanied with the visual feedback is enough to gather most of the information about a certain environment. It increases the precision of teleoperation and sensation levels of the virtual reality (VR) applications by exerting physical properties of the environment such as forces, motions, textures. Currently, haptic devices find use in many VR and teleoperation applications. The objective of this thesis is to design a novel Six Degree-of-Freedom (DOF) haptic desktop device with a new structure that has the potential to increase the precision in the haptics technology. First, previously developed haptic devices and manipulator structures are reviewed. Following this, the conceptual designs are formed and a hybrid structured haptic device is designed manufactured and tested. Developed haptic device.s control algorithm and VR application is developed in Matlab© Simulink. Integration of the mechanism with mechanical, electromechanical and electronic components and the initial tests of the system are executed and the results are presented. According to the results, performance of the developed device is discussed and future works are addressed.
  • Master Thesis
    Unlimited-Wokspace Teleoperation
    (Izmir Institute of Technology, 2012) Şahin, Osman Nuri; Dede, Mehmet İsmet Can
    Teleoperation is, in its brief description, operating a vehicle or a manipulator from a distance. Teleoperation is used to reduce mission cost, protect humans from accidents that can be occurred during the mission, and perform complex missions for tasks that take place in areas which are difficult to reach or dangerous for humans. Teleoperation is divided into two main categories as unilateral and bilateral teleoperation according to information flow. This flow can be configured to be in either one direction (only from master to slave) or two directions (from master to slave and from slave to master). In unlimited-workspace teleoperation, one of the types of bilateral teleoperation, mobile robots are controlled by the operator and environmental information is transferred from the mobile robot to the operator. Teleoperated vehicles can be used in a variety of missions in air, on ground and in water. Therefore, different constructional types of robots can be designed for the different types of missions. This thesis aims to design and develop an unlimited-workspace teleoperation which includes an omnidirectional mobile robot as the slave system to be used in further researches. Initially, an omnidirectional mobile robot was manufactured and robot-operator interaction and efficient data transfer was provided with the established communication line. Wheel velocities were measured in real-time by Hall-effect sensors mounted on robot chassis to be integrated in controllers. A dynamic obstacle detection system, which is suitable for omnidirectional mobility, was developed and two obstacle avoidance algorithms (semi-autonomous and force reflecting) were created and tested. Distance information between the robot and the obstacles was collected by an array of sensors mounted on the robot. In the semi-autonomous teleoperation scenario, distance information is used to avoid obstacles autonomously and in the force-reflecting teleoperation scenario obstacles are informed to the user by sending back the artificially created forces acting on the slave robot. The test results indicate that obstacle avoidance performance of the developed vehicle with two algorithms is acceptable in all test scenarios. In addition, two control models were developed (kinematic and dynamic control) for the local controller of the slave robot. Also, kinematic controller was supported by gyroscope.
  • Master Thesis
    Position / Force Control of Systems Subjected To Communicaton Delays and Interruptions in Bilateral Teleoperation
    (Izmir Institute of Technology, 2012) Uzunoğlu, Emre; Dede, Mehmet İsmet Can
    Teleoperation technology allows to remotely operate robotic (slave) systems located in hazardous, risky and distant environments. The human operator sends commands through the controller (master) system to execute the tasks from a distance. The operator is provided with necessary (visual, audio or haptic) feedback to accomplish the mission remotely. In bilateral teleoperation, continuous feedback from the remote environment is generated. Thus, the operator can handle the task as if the operator is in the remote environment relying on the relevant feedback. Since teleoperation deals with systems controlled from a distance, time delays and package losses in transmission of information are present. These communication failures affect the human perception and system stability, and thus, the ability of operator to handle the task successfully. The objective of this thesis is to investigate and develop a control algorithm, which utilizes model mediated teleoperation integrating parallel position/force controllers, to compensate for the instability issues and excessive forcing applied to the environment arising from communication failures. Model mediation technique is extended for three-degrees-of-freedom teleoperation and a parallel position/force controller, impedance controller, is integrated in the control algorithm. The proposed control method is experimentally tested by using Matlab Simulink blocksets for real-time experimentation in which haptic desktop devices, Novint Falcon and Phantom Desktop are configured as master and slave subsystems of the bilateral teleoperation. The results of these tests indicate that the stability and passivity of proposed bilateral teleoperation systems are preserved during constant and variable time delays and data losses while the position and force tracking test results provide acceptable performance with bounded errors.