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Humanoid robots are robots that are similar in appearance and performance to humans. Designing and controlling a humanoid robot to perform such supposedly ordinary tasks as walking, running, writing, talking, driving, riding bikes, and the like is such a difficult task from the control point of view that it seems to be quite ambitious and inaccessible. In this thesis, the previous efforts of scientists and researchers are presented using different intelligent controllers. Additionally, the dynamic analysis of selective biped (seven-link biped robot) is illustrated. In this research, we present a method to control the walking of the biped robot while retaining stability. In this method the... 

In the present study, an adaptive sliding mode control method was employed to control a fish robotic system using the method of hardware in the loop. Following the introduction of the nonlinear model for the robot, elongated body theory, suggested by Lighthill, was used to analyze fish movements. Lighthill’s theory inspired from slender body theory in aerodynamics scope could be viable to exercise upon the carangiform mode of swimming. By simplifying Lighthill’s equations in planar motion of fish robot, the number of degrees of freedom exceeds the number of the control variables. In view of the fact that the presented model is an under-actuated model, there exist some parametric and... 

Laparoscopic surgery is a branch of minimally invasive surgery that is implemented in the abdominal cavity. This kind of surgery is conducted using surgical instruments that are inserted into the abdomen through some small incisions created on its wall and the necessary vision is provided for the surgeon using a laparoscope lens that is inserted through the first created incision. In recent years, because of its advantages, controlling and manipulation of the lens is done using some robots instead of surgeon assistant. To facilitate the controlling procedure of these robots for the surgeon, several controlling modes such as keyboard, foot switch, and voice commands are presented. Robolens is... 

Stroke is the main cause of disability in the world and the third cause of death, so spreading rehabilitation technique for post stoke patients is one of the most important targets un these days. The first prototype hand rehabilitation device was designed and fabricated in RCSTIM in 2008. Since the first prototype had been proved its effectiveness in clinical tests in the next phase industrial production of the device had to be considered at first all of the problems that had been observed during the clinical tests had to be solved for the future production. In the first series of experiments, clinical limitation and the interaction between the patient and the physiotherapist with the device... 

The application of manipulators is becoming more and more popular in objects handling especially when it is desired to have access to remote areas in destructive or hazardous taskspaces. For this purpose, a hand-like mechanism must be designed to be used as an end-effector, which can grasp objects. In this paper a cable driven grasping mechanism has been presented. In the proposed mechanism each finger consists of three phalanxes which are actuated by a single motor. Also, locking and unlocking constraints are used in the mechanism in order to generate an anthropomorphic motion, in which, the order of reaching phalanxes to the object is sequential, in such a way that each phalanx starts... 

In this work, we want to gain and analyze the dynamic equations of an open four bar mechanism with two flexible links and three flexible hinges. In continue, one of the applications of a 3-RRR mechanism has been mentioned and dynamic equations and angles behavior have been analyzed. The effect of hinge stiffnesses and their sequence has been investigated by using Hamilton principle. In addition, The behavior of the mechanism with flexible links has compared to the mechanism with non-flexible. At last, the results have been validated by ADAMS software.

 

All humanare subject to a physiligical phenomenon known as tremor, which introduces unintended, relatively high frequency movments into various limbs. This involuntary movment is main reason of human disability in doing of precision tasks. Precision surgery like eye surgery is among them that surgeons must have very ittle tremor to enable them to oprate on the small anatomy of the eye. In this reaearch by emphasizing on reduction of muscle fatigue in precision surgery, weight balancing mechanism designed and analyzed. Fatigue is most important cause of tremor, thus we expected tremor amplitude reduce by reduction of muscle fatigue. Purpose mechanism is passive mechanism that balances the... 

Nowadays, World is witnessing an epidemic increase in Robotic Concepts and its usage in diverse fields such as Explore and Rescue Missions, Conservation and Guarding of Environments and various Millenarian Applications. While, different Goals like increasing the precision and speed of missions performance, and decreasing the costs have been always the major priorities in design and building robots. One of the best methodologies to achieve aforementioned goals is to replace a highly capable robot with a group of simple and restricted robots. This suggestion is inspired by the nature and lots of its animals, like birds, fishes and insects. These creatures use socializing in order to forage and... 

Swarm Robotics consists of homogonous robots with considerable abilities. In recent years, engineering applications, including multi-agent control and air vehicles have been existed and engineers have been interested more in multi-agent systems. Currently, progressive number of studies is being done on decreasing the expenses, developing applicability and compactness of robots. Exchanging some simple robots with a complicated robot results omitting over-complexity and expensive equipments. This project is looking for a method for emerging connectivity and consequently maintaining it for a swarm robotic suffering from limited communication. Limited communication means that agent distinguish... 

The capability to control and maintain upright posture is a fundamental requirement for humanoid robots. Although many control algorithms were successfully presented, it seems developing a new controller inspired from human balance strategy would greatly improve performance and reduce energy consumption. To study the control strategy used by human nerves system more precisely, a balancing exercise was designed and implemented. Five human subjects were asked to stand on an unstable tilting board and balance the board. Instantaneous Eulerian angles of body segments of human subjects were captured by utilizing Xsense orientation sensors. A humanoid robot standing on the tilting board was... 

In this thesis control of wheeled mobile manipulators for cooperative object transportation is investigated. Full dynamic model of a mobile manipulator with a three wheeled mobile base and a three DOF manipulator is derived using Gibbs-Appell method. Input-output linearization technique is used to control individual robots. Transporting the object is divided into two steps, first robots use a decentralized behavior-based method to approach and surround the object. Then virtual structure method is used to control the robots to transport the object cooperatively. Simulation results with three robots handling an object are presented to show the effectiveness of proposed method  

As technology develops, the need of instruments which could be used for improving the rate and accuracy of the manufacturing increases. This makes the robots inevitable to use in most industries. Among the robots, cable-driven robots have special characteristics that increase the tendency of using them.Multi-body cable-driven robots are novel type of cable-driven robots that have advantages compared to single-body ones. Capability of use in rehabilitation applications, in which the different parts of human body have to move separately, is one of the advantages of multi-body cable-driven robots.The first aim of this thesis is to extend the tensionable workspace concept for multi-body... 

Nowadays, by increasing the applications of robots in military, industry and also home usages, researchers are looking for the most efficient algorithms to control the robots. As Prof. Zadeh presented the fuzzy systems in 1965 as a proper probabilistic logic, fuzzy control has been developed and now is one of the most applicable procedures in new aspects of controlling because of its less required computational capacity and more proper stability. Although the human like and quadruped robots are more applicable because of their coincidence with more difficult conditions compared to the wheeled robots, more complicated methods should be implemented to control them.The main subject of this... 

In this thesis, the equations of motion of a beam with tip mass on flying support, based on Euler-Bernoulli and Timoshenko beam theories is derived. To attempt for having accurate model in high rotational speeds, stretch variable is considered and employed in the equations of motion. For a planar and a spatial rotating beam, equations of motion are lineralized and simulated. Finite Element Method and Newmark direct integration scheme are employed for the analysis of the governing equations. To support the numerical results, an experimental setup is designed and based on which different tests are performed. A cantilever beam on a flying support free to vibrate in three dimensions is... 

In recent years with advancement of Robotics, the applications of wide scale use of robots in our homes is not as far-fetched as it was before. One of the important problems for an indoor robot is moving inside a new and unknown environment. To achieve this, the robot should, with the help of its sensors, not only calculate its location; but should also build a map of the environment for later use. Additionally, the robot must be able to explore this unknown environment. The most important drawbacks of the classical solutions to these problems are long computation times, heavy memory usage and absence of precision. In recent years, large amount of research effort has put on solving these... 

This research describes the design and analysis of an actuating robot to manipulate the disposable Endo-wrist robotic surgery instruments. Analyzing the mechanism of common manual Endo-wrist instruments, it was found that the rotations of handle of the instrument are transferred to its wrist using a snake-like element and four connecting cables. Based on this observation, a 2DOF parallel actuating robot was designed to rotate the instrument handle, in which the degrees of freedom are controlled by two linear spindle motors. The Inverse kinematic analysis of the manual instrument was performed by minimizing the potential energy of cables. Also the inverse kinematic solution of the actuating... 

in laparoscopic surgeries, act zone tissues are not directly palpable for the surgeon. Therefore, evaluating the mechanical behavior of the tissue and distinguishing healthiness or illness of that, are not achievable for the surgeon. In this treatise, the matter of discerning the soft and bulky tissues mechanical properties by a robotic arm during the laparoscopic surgery, is regarded. In first step, a tool like a two finger miniature hand was designed in which either of fingers have utilized a parallelogram mechanism for opening and closing. The dimensional design of the mechanism was undertake in away that the tool has the ability of going through a 10mm diameter path and grabbling and... 

Today, many surgical procedures such, gallbladder, gastric bypass, placement of a ring around the stomach, partial removal of colon, removal of tumors use laparoscopic techniques. In this surgery, a variety of tools to capture and remove the internal organs can be used. Sometimes the surgeon selects the proper tools and replacement during surgery, so the surgeon had to do different things with the operation. These tools generally cannot be used because of the large internal organs device is small and does not have enough degrees of freedom. In laparoscopic surgery, the surgeon operate in the abdominal cavity using a thin instrument that is inserted through the trocar hole would do. If... 

This thesis is devoted to deriving a port Hamiltonian control approach for different scenarios of brachiation movement by a two-link underactuated planar robot called brachiation robot. The port Hamiltonian modeling and control of this type of robot is introduced for the first time and shows promising results in the analysis and simulation as will be showed here. Animals have long inspired roboticists. Their dexterity, versatility, flexibility of motion and great variety of behaviors has made them benchmarks for robot performance. Recently things have begun to change and robots are now capable, to a limited degree, of mimicking the behavior of animals. This paper studies a type of... 

This paper proposes a globally and exponentially convergent predictor observer for attitude and position estimation based on landmark measurements and velocity (angular and linear) readings. It is assumed that landmark measurements are available with time delay. The maximum value of the sensor delay under which the estimation error converges to zero is calculated. Synthesis of the observer is based on representation of the rigid-body kinematics and the sensor delay by a combination of ordinary and partial differential equations (ODE-PDE). An observability condition specifies necessary and sufficient landmark configuration for convergence of attitude and position estimation error to zero....