The problem of constrained nonlinear tracking control for a small fixedwing unmanned air vehicles (UAV) is considered. With the UAV equipped with lowlevel autopilots, the twelve-state model of the UAV is reduced to a six-state model with heading, air speed, and altitude command inputs. Three different approaches based on the state dependent Riccati equation (SDRE), Sontag’s formula, and aggress...

The robust optimal attitude control problem for a flexible spacecraft is considered. Two optimal sliding mode control laws that ensure the exponential convergence of the attitude control system are developed. Integral sliding mode control ISMC is applied to combine the first-order sliding modewith optimal control and is used to control quaternion-based spacecraft attitudemanoeuvres with externa...

In the last few years, algorithms using state-dependent Riccati equations (SDREs) have been proposed for solving nonlinear control problems. Under state feedback, pointwise solutions of an SDRE must be obtained along the system trajectory. To ensure the control is well-defined, global controllability and observability of state-dependent system factorizations are commonly assumed. This paper rig...

In this paper, a nonlinear optimal control approach is proposed to plan the motion of a redundant free-floating space manipulator (FFSM) when carrying a heavy payload. Optimal joint trajectories are determined to track a desired end-effector path, for which limitations of the manipulator’s load-carrying capacity and tracking accuracy are simultaneously considered. In this method, FFSM is descri...

An autonomous robot with vertical take-off and landing (VTOL) capability could be useful for many applications including search and rescue, exploration in hazardous environments, monitoring, surveillance and investigation or even for intelligence. However design of a flight control system for a small UAV is a challenging task. Unlike in conventional aircrafts the control algorithm has to be imp...

A better understanding of the antimicrobial susceptibility, carriage of virulence determinants and molecular characteristics of Staphylococcus aureus isolates associated with skin and soft tissue infections (SSTIs) may provide further insights related to clinical outcomes with these infections. From January 2012 to September 2013, a total of 128 non-duplicate S. aureus isolates were recovered f...