Kamran Turkoglu

Kamran Turkoglu

This paper presents real-time guidance strategies for unmanned aerial vehicles (UAVs) that can be used to enhance their flight endurance by utilizing {\sl insitu} measurements of wind speeds and wind gradients. In these strategies, periodic adjustments would be made in the airspeed and/or heading angle command for the UAV to minimize a projected power requirement at some future time. In this paper, UAV flights are described by a three-dimensional dynamic point-mass. Onboard closed-loop trajectory tracking logics that follow airspeed vector commands are modeled using the method of feedback linearization. A generic wind field model is assumed that consists of a constant term plus terms that vary sinusoidally with respect to the location. To evaluate the benefits of these strategies in enhancing UAV flight endurance, a reference strategy is introduced in which the UAV would seek to follow the desired airspeed in a steady level flight under zero wind. A performance measure is defined as the average power consumption both over a specified time interval and over different initial heading angles of the UAV. A relative benefit criterion is then defined as the percentage improvement of the performance measure of a proposed strategy over that of the reference strategy. Extensive numerical simulations are conducted. Results demonstrate the benefits and trends of power savings of the proposed real-time guidance strategies.

Ankyda Ji, Kamran Turkoglu

This paper explains the integration process of an autonomous quadcopter platform and the design of Arduino based novel software architecture that enables the execution of advanced control laws on low-cost off-the-shelf products based frameworks. Here, quadcopter dynamics are explored through the classical nonlinear equations of motion. Next, quadcopter is designed, built and assembled using off-the-shelf, low-cost products to carry a camera payload which is mainly utilized for any type of surveillance missions. System identification of the quadcopter dynamics is accomplished through the use of sweep data and $CIFER^{\circledR}$ to obtain the dynamic model. The unstable, non-linear quadcopter dynamics are stabilized using a generic control algorithm through the novel Arduino based software architecture. Experimental results demonstrate the validation of the integration and the novel software package running on an Arduino board to control autonomous quadcopter flights.

Fei Sun, Kamran Turkoglu

This work investigates the consensus problem for multi-agent nonlinear systems through the distributed real-time nonlinear receding horizon control methodology. With this work, we develop a scheme to reach the consensus for nonlinear multi agent systems under fixed directed/undirected graph(s) without the need of any linearization techniques. For this purpose, the problem of consensus is converted into an optimization problem and is directly solved by the backwards sweep Riccati method to generate the control protocol which results in a non-iterative algorithm. Stability analysis is conducted to provide convergence guarantees of proposed scheme. In addition, an extension to the leader-following consensus of nonlinear multi-agent systems is presented. Several examples are provided to validate and demonstrate the effectiveness of the presented scheme and the corresponding theoretical results.