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In this thesis, modeling and dynamic analysis of a micro-robot motion in stick-slip-jump mode are studied. Stick-slip is one of the more common principles of locomotion for micro-robots. Stick-slip locomotion relies on friction, and requires the robot to continuously maintain contact with the substrate. By increasing the actuation force on the micro-robot (i.e. by increasing the input voltage amplitude or frequency), the micro-robot losses contact with the substrate, and the stick-slip principle is no longer valid. Under this condition, instead of the stick-slip mode, a combination of stick-slip motion and jumps governs the locomotion. We refer to this as stick-slip-jump locomotion. In... 

Separate analysis of modern systems by continuous or discrete theories is not possible, because they cannot solely express the detailed descriptions of a system. As a result of this, researchers are motivated to study hybrid systems. Specific class of hybrid systems which consists of several continuous subsystems and a rule that specifies how to switch between them, is called a switched system. Recently, many studies have been done on the stability and control of switched systems. In this regard, the goal of present study is presenting applications of switched systems using two control methods. The first application is control of a chemical reactor system with multiple modes. We presented... 

Rotor-dynamics is an important field of study in dynamical systems. Because of demands for rotary machines with high speeds such as turbines, pumps, fans, spindle machines and so on, the dynamic and stability analysis of these systems are considered over a hundred years. As some of the rotor systems are supported by rolling bearings with radial clearance, the dynamic and stability analysis of such systems can be helpful in the corresponding areas of the industry. In this thesis by utilizing regional stsbility concept, the Hybrid analysis of system is performed. The system includes a rigid and symmetric rotor which has two degrees of freedom. The bearings are considered to be tapered roller... 

Foot movement is one of the most powerful and adaptable methods of movement in nature. Inspired by humans, the most intelligent creatures on earth, bipedal robots have many uses. In this research, a control method for running a bipedal robot has been designed. In the simulation part of the five-link model, the robot's motion equations for running and walking at different levels are extracted by the Lagrange method. In path generation, using the two-layer optimization method and holonomic and dynamic constraints, optimal paths are produced which are kinematically and dynamically possible (feasible). Additionally, path generation is facilitated by an invariant impact constraint to ensure the...