Recently developed, second-order sliding-mode control (2-SMC) algorithms are analyzed to assess their global convergence properties. While standard first-order sliding-mode control (1-SMC) algorithms derive their effectiveness from the global solution of the well known “reaching condition” _ ( = 0 being the actual sliding manifold), 2-SMC is based on more complex differential inequalities, for ...

In this paper, a decentralized asymptotic fault tolerant control system is proposed for near space vehicle (NSV) attitude dynamics. First, NSV reentry mode is described, and the actuator failure model is developed whose behavior is described by high-order dynamics. Next, the multi-model based fault diagnosis and identification (FDI) algorithm is proposed for high order actuator dynamics, which ...

Thermoacoustic instability is frequently found in continuous combustion processes in propulsion, power generation, and heating. Active control has been increasingly pursued in recent years to suppress the pressure oscillations which result from this instability, while maintaining performance objectives such as low NOx emission and high efficiency. This thesis considers the physics behind the th...

in this paper the design of a biped robot actuated with shape memory alloy (sma) springs with minimum degrees of freedom is presented. sma springs are a class of smart materials that are known for their high power to mass and volume ratios. it was shown that utilizing spring type of smas have many advantages as large deformation, smooth motion, silent and clean movement compared to ordinary typ...

Trajectory generation has traditionally been formulated on the assumption that the environment is flat. On rough terrain, however, deviations of the angular velocity vector from the vertical lead to errors which accumulate in a manner similar to the accumulation of attitude errors in odometry. In practice, feedback control can compensate for these errors in modeling by adjusting the path in rea...

Current efforts are focused on assembling new constructions while applying non-conventional actuators, for example, artificial pneumatic muscles, in engineering manufacturing processes. The reason is to eliminate stiffness and inflexibility of equipment structures that make sharing the working space technological complicated. This article presents results experimental measurements pressures mus...

Active hydraulic mounts with an inertia track, decoupler membrane, and oscillating coil actuator (AHM-IT-DM-OCAs) have been studied extensively due their compact structure large damping in the low-frequency band. This paper focuses on a comprehensive analysis of active passive dynamics fixed points mid-low-frequency bands, which will be helpful for parameter identification. A unified lumped mec...

T HE progress being made in computational fluid dynamics provides an opportunity for reliable simulations of such complex phenomena as laminar-turbulent transition. The dynamics of flow transition depends on the instability of small perturbations excited by external sources. Computational results provide complete information about the flowfield that would be impossible to measure in real experi...