Control Structure Design and Implementation for Eye Surgery Training Dual Master Haptic System
Surgery training have always been one of the most important challenges for the surgeons. Owing to the higher accuracy required in eye surgery than in other surgeries, any mistake made by the trainee might lead to undesired complications for the patient. Recently, dual-user haptic systems consisting of two haptic consoles, one for the trainer and one for the trainee, has been developed as an assistive tool to facilitate surgery training. In these systems, the trainer and the trainee collaboratively perform surgical tasks through their haptic consoles. In the proposed surgery training haptic system, the environment is directly manipulated by one surgeon and the other surgeon is indirectly involved in the procedure through the haptic system. This makes a special training framework which is applicable to not only virtual environment but also real environments such as physical phantoms, cadavers and patients with special focus on the vitrectomy surgery. Initially, the surgery is directly performed by the trainer and the position of the trainer is transformed to the trainee’s hands through the haptic system. Utilizing this step, the trainee can increase his/her expertise in different tasks by learning the true movements. After obtaining the required level of surgical skills, the trainee can perform the surgery directly on the environment with trainer’s supervision. To avoid undesired complications, the trainer is able to interfere into the procedure in the case of sudden mistakes happens by the trainee. Due to the interaction between the users in the dual user haptic systems, the decision of each user is affected by the other user. Hence, new application-based control structures are required to be further investigated. The majority of the previously proposed control methodologies for this system have not simultaneously considered special requirements of surgery training and stability analysis of the nonlinear closed-loop system which is the objective of this thesis. In order to describe the objectives and facilitate controller design for dual user haptic systems, this thesis introduces two training approaches including Expert Continual Action (ECA) and Expert Supervision & Intervention (ES&I). The ECA training approach is based on the trainer to perform all details of surgical operation, while the trainee freely experiences the task and receives the haptic guidance signals from the trainer. The control schemes based on ECA are appropriate for the most primary level of training in which the trainee does not have sufficient experience to perform the operation. On the other hand, the ES&I training approach is based on giving the trainee the chance to conduct the surgical operations and be supervised and corrected as needed, while the trainer is provided with the facilities to interfere in the operation and correct probable mistakes made by the trainee. In this approach, the trainer is not required to be involved at every stage of surgical procedures. Thus, the trainer is just given a supervisory role to interfere with the procedure only when a mistake is performed by the trainee. Notably, a unique feature of the proposed training structure is its application to remote training with real environment. In this case, one surgeon holds the surgical instrument and directly performs the surgical procedure, whereas the other surgeon is indirectly involved in the surgical operation through the haptic system. This requires a specially designed haptic system for each surgical task to provides the necessary movements required for that surgery. This issue is specially studied for the vitrectomy surgery and the designed haptic system is presented. In brief, the main contribution of this thesis is to introduce the above training approaches and develop some control schemes based on each training approach. Each control scheme is developed based on its respective training approach by utilizing the necessary mathematical tools of control theory. The stability of the closed-loop system for each control scheme is studied using input-to-state stability (ISS) analysis. Besides, some simulation and experimental results are presented to support the proposed methodologies. Finally, the specially designed haptic system for facilitating vitrectomy surgery training is presented.
|Mohammad Mahdi Share Pasand|
Extension of Robust Internal Model Control to Linear singular systems
In this thesis, the problem of singular control systems is studied in detail. Singular systems arise naturally in process control as well as other fields. Existing control algorithms are discussed and their advantages and disadvantages are compared to each other. A new method in state space is presented for state observation and disturbance attenuation. A robust control scheme for uncertain singular systems is proposed in the frequency domain in order to yield to an offset free, robust, disturbance ejective closed loop system, whose performance is superior to that of conventional state space methods. The problem of algebraic loop and its relation to the regularity concept is illustrated and an algorithm to avoid algebraic loop is proposed. The proposed method for avoiding algebraic loops is incorporated in the control system. Moreover, it is shown that the internal model control scheme for singular systems is an extension of the internal model control algorithm for standard systems. Therefore, the thesis makes an extension of the internal model control into the singular systems. Several examples were provided and the results were simulated to show the effectiveness of proposed methods.
|2010||M.Sc.||Dynamical Systems Analysis and Control|
|Mohammad M. Aref|
طراحی و تحلیل سینماتیکی و دینامیکی روبات موازی کابلی افزونه دانشگاه صنعتی خواجه نصیرالدین طوسی
روبات موازي كابلي KNTU CDRPM پروژهاي است كه در گروه روباتیک ارس جهت تلفيق و كاربرد تكنولوژيهاي نوين و معرفي نسل جديدي از روباتهای صنعتی به جامعة علمي کشور تعريف شده است. یکی از کاربردهای اين روبات حمل و جابجایی دقیق تجهيزات اپتيكي مربوط به تابش اشعه ليزر است كه در جوشکاری دقیق سه بعدی قطعات فلزي استفاده می شود. در این پایاننامه، طراحی و تحلیل سینماتیکی و دینامیکی روبات موازی کابلی دانشگاه صنعتی خواجه نصیرالدین طوسی مورد مطالعه قرار گرفتهاست. همچنین توسعه روباتهاي موازي کابلی براي كاربردهاي دیگر نگاه كليتري است که در اين طراحي مورد تعقیب قرار گرفته است. بدین منظور نخست با معرفی روباتهای موازی موجود در مراکز صنعتی و تحقیقاتی، ادبیات موضوع مورد کنکاش قرار گرفته و سپس با معرفی و تحلیل معیارهای طراحی گامی در راه طراحی دقیق این نوع روباتها برداشته شدهاست. مبانی منطقی طرحهای اولیه بررسی شدهاست تا طرحی پایه برای KNTU CDRPM جهت بهینهسازی معرفی شود. در طراحی بهینه، روشی تحت عنوان بازبینی نظارتی پیشنهاد گردیدهاست. این روش همچنین جهت تعیین وزنهای توابع هزینه در تابع هزینهی کل مفید میباشد. مراحل یاد شده بر روی روبات بکاربسته شدهاست تا ابعاد و مشخصات بهینه برای این روبات کشف شود. نتايج حاصل از تحليل نشان ميدهد كه روبات KNTU CDRPM از فضاي كاري وسيعتر و ماهرتري نسبت به ساير انواع روباتهاي موازي و روباتهاي موازي كابلي بهره ميبرد. این مهم در نتیجهی تحلیلهای سینماتیکی و دینامیکی مرتبط، صحه گذاری میگردد.
|2009||M.Sc.||Parallel and Cable Robotics|
|Mohammad Mehdi Nazeri Ardakani|
Victor's robotic arm simulation and torque control design and implementation on it
Today robots have different applications, from industrial environments to urban traffic environments, natural environments, office buildings and residential and so on. precise control of motion of mobile robot arms is very important. mobile robot is the fourth generation of mobile robot robots which is designed and built in the KN2C laboratory of the Aras robotic group .In this thesis , torque control methods are implemented in order to accurately control the robot 's arm .Initially, the complete 3D model of the robot was prepared by linking the output of SolidWorks software to MATLAB software, and this model was used in a MATLAB simulation toolbox called Simscape.By adding torque sensors and actuators to this model, a suitable simulator of the real dynamic behavior of the robot arm has been prepared. Then, by performing identification experiments, a linearized model of the robot was obtained with compensation and without mechanical compensation of arm weight, and these models were used to design torque controllers. Quantitative evaluation of robot movement accuracy has been investigated and reported using this method in comparison with previous robot controllers. It has been observed that the use of torque control with the systematic method presented in this dissertation can be a good vehicle for implementing controllers designed on a real robot.