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The paper present a theoretical investigation of the propagation of Love waves past an anisotropic fluid saturated porous layer with irregular periodic boundaries and sandwiched between two elastic isotropic half spaces. The porous layer is assumed to be initially stressed. Fourier series expansion has been implemented to describe the irregular boundaries of the layer. Using appropriate boundary conditions a closed form dispersion and absorption relation for Love wave in the porous layer have been derived. The dispersion equation has been investigated extensively through numerical calculation for particular irregular interface to explore the effect of non dimensional average thickness and the periodic roughness of the boundaries on the phase velocity of Love wave. Also the effect of initial stress as well as the porosity on wave velocity is studied. A comparative study has been carried out through various graphs to study the consequence of different parameters on the phase velocity between porous and corresponding non porous layer. A close compliance is also established in some special cases to the existing solutions available from analytical methods. [ABSTRACT FROM AUTHOR]

In this paper an attempt has been made to derive the frequency equation of torsional surface waves in initially stressed fiber reinforced layer lying over fluid saturated anisotropic porous half space under gravity. The dispersion equation has been obtained in terms of Whittaker function and its derivatives, which further expanded asymptotically and retain the terms upto second degree. The analysis of frequency equation bear out the pronounced effect of initial stress, transverse and longitudinal rigidity of reinforced material, gravity and porosity of the porous half space on the propagation of torsional surface waves. Moreover, it can be noted that in the absence of initial stress, reinforcement parameters, gravity and porosity, the frequency equation of torsional surface waves reduces to dispersion equation of Love waves in isotropic layer. This ensures the classical result that torsional surface waves do not propagate through isotropic homogeneous medium. [ABSTRACT FROM AUTHOR]

Artificial cognitive systems are increasingly drawn towards 'human‐like' gestural exhibits while performing various manipulative acts. Representing such actions in a natural settings requires temporal extractions of their grasp progressions. A novel optimisation‐based hidden Markov framework is offered, to generate natural hand prehensions through maximisation of a composite grasp function built of individual finger trajectory likelihoods. In order to produce the desired motion in an intuitive framework, the final grasp frame (represented in terms of standard discriminants z ∈ ℜ2 in a condensed grasp eigen‐space) is extended in a temporal sequence by equi‐spaced increments of z, over their conventional joint‐space representations. [ABSTRACT FROM AUTHOR]

Grasping postures on a human hand are generated by an effective combination of spatial motions and contact forces on individual finger linkages. The rich kinematic redundancy within its anatomy, poses critical control challenges, while emulating natural prehensile actions. A simplified grasp‐formulation resolution is presented, by proposing a virtual‐object imagery to define generic grasp enaction sequences. The same are conceived and controlled by a set of contact points on the imagined grasp‐sphere, whose spatial conformation is guided by a serial‐haptic interface. The kinaesthetic cognitions along with visual feed to an operator ushers a reliable framework for grasp execution and transfer to a robot hardware without resorting to supplementary mapping mechanisms. Stable grasps on the anthropomorphic robot set‐up portrays a systematic procedure to transcribe human‐like postural attributes, aided with somesthetic and visual sensations that are anticipated to steer remote operator controls. [ABSTRACT FROM AUTHOR]

Artificial cognitive systems are increasingly drawn towards human-like' gestural exhibits while performing various manipulative acts. Representing such actions in a natural settings requires temporal extractions of their grasp progressions. A novel optimisation-based hidden Markov framework is offered, to generate natural hand prehensions through maximisation of a composite grasp function built of individual finger trajectory likelihoods. In order to produce the desired motion in an intuitive framework, the final grasp frame (represented in terms of standard discriminants z ∈ R² in a condensed grasp eigen-space) is extended in a temporal sequence by equi-spaced increments of z, over their conventional joint-space representations. [ABSTRACT FROM AUTHOR]