This paper investigates the design of a novel nonlinear L 1 adaptive control architecture to stabilize and control an aircraft with structural damage. The airplane nonlinear model is developed considering center of gravity variation and aerodynamic changes due to damage. The new control strategy is applied by using nonlinear dynamic inversion as a baseline augmented with an L 1 adaptive control strategy on NASA generic transport model in presence of un-modeled actuator dynamics, wing and vertical tail damage. The L 1 adaptive controller with appropriate design of filter and gains is applied to accommodate uncertainty due to structural damage and un-modeled dynamics in the nonlinear dynamic inversion loop, and to meet desired performance requirements. The properties of the proposed nonlinear adaptive controller are investigated against a model reference adaptive control, a robust model reference adaptive control, and an adaptive sliding mode control strategy. The results clearly represent the excellent overall performance of the designed controller.

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In this study, the process of designing a motion optimization algorithm for swarm quadrotor robots is presented. Motions equations of swarm are written based on Lagrangian energy equations. A potential function is applied on the equations to optimize the swarm motion. The applied potential function enables each of the swarm members to move toward an independent target coordinate as motion starts and simultaneously connecting with other members. As a result, the necessity of having the members aggregated within an area close to the swarm center is eliminated. This algorithm is supposed to act on swarm of quadrotors; therefore a validated dynamic model of quadrotor and a designed controller are introduced to discuss the possible applications. The designed algorithm is then applied to grasp an object. In order to establish grasping, particle swarm optimization method is used. Finally, the algorithm is simulated in MATLAB for a two-member swarm of quadrotors for grasping the object. Simulation results indicate increased work space for the members along the motion path and reduced mission time.

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