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This work proposes a singularity free stabilizing controller for a non-holonomic mobile robot. The control objective is to force the system states from any initial position to the origin in finite time. In the first step the state transformation has been done on the kinematic and dynamic model of the mobile robot. After transformation the kinematic and dynamic model has been converted to non-holonomic integrator and non-holonomic double integrator respectively. Further a novel sliding surface has been proposed in the paper which stabilizes both non-holonomic integrators in finite time. Kinematic stabilization has been done using power rate reaching law of sliding mode controller (SMC) and dynamic stabilization of mobile robot has been done using relay free SMC technique. Stability analysis of the proposed kinematic and dynamic controller has been given using Lyapunov stability theory. Simulations studies are performed, and it is shown that the proposed controller is better than the existing state of the art.

This paper proposes path tracking of non-holonomic mobile robot using event-triggered control in presence of time and state dependent uncertainty. A non-holonomic mobile robot is an underactuated system where, two control input drives the three system states to the desired value. The controller is developed in two steps. In first step an eventtriggered kinematic controller is designed to reduce the effort of the actuator. The event-triggering conditions are derived using Lipschitz method. In second step a dynamic controller has been designed which offers robustness towards time and state-dependent uncertainty. To reject the time dependent uncertainty twisting controller is used and to reject the state-dependent uncertainty adaptive tuning laws are derived using Lyapunov stability theory. Simulations has been done for different types of trajectory tracking.

This paper proposes a novel switched system based control strategy to neutralize cyber enabled switching attacks on smart grids. The focus of this work revolves around demonstrating the immunity of the smart grid against attacks involving the intruder trying to switch the load that is connected to one or more generators on the grid. The work utilizes the concept of Common Lyapunov function (CLF) to maintain the transient stability under any arbitrary switching attack. The stability of the switched system is assessed using Lyapunov’s stability theory and the condition for system stability is obtained in terms of sum of square (SOS) constraints. The CLF and control gain are simultaneously estimated in the proposed approach. The effectiveness of the proposed control strategy is evaluated using numerical simulations, against coordinated switching attacks. It can be observed that the proposed scheme is able to maintain stable grid operation even in the presence of a cyber intrusion.