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Summary In this paper, a simplified super‐twisting control with adaptive gain is proposed for a class of nonlinear uncertain systems. A strong Lyapunov function is constructed to design a sliding mode controller with adaptive gain. Furthermore, the analysis of the finite time convergence towards the equilibrium point of the closed‐loop system is detailed. Regarding previous works from literature, the main contribution of this approach is the simplification of the gain tuning process by maintaining a high level of performance. Finally, simulation results for tracking control of a quadrotor are given to show the performance of the proposed algorithm.

Congenital abdominal wall defects that are located outside of the anterior wall are extremely rare and difficult to classify because there are no well accepted guidelines. There are two regions outside of the anterior wall: the flank or lateral wall; and the lumbar region. We report the case of a patient with an oval 3 cm-diameter hernia defect located above the anterior axillary line, which affects all layers of the muscular wall. An anorectal malformation consisting of a recto-vestibular fistula was also identified, and chest X-ray showed dextrocardia. The suggested treatment is repair of the defect before 1 year of age. Given that the anomalies described may accompany lateral abdominal wall hernia, it is important to diagnose and treat the associated defects.

In this manuscript, the design of a continuous super twisting control based on high-order sliding mode observer for a class of nonlinear systems is addressed. An analysis of stability of the system in closed loop with the proposed control-observer scheme is provided by means of Lyapunov approach, where sufficient conditions are given to ensure the convergence in finite time. Furthermore, a comparative study against similar methodologies is provided, where simulation and experimental results illustrate the effectiveness of the proposed scheme for altitude control of a quadrotor aircraft.