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Using the dynamic inversion philosophy, a nonlinear partial integrated guidance and control approach is presented in this paper for formation flying. It is based on the evolving philosophy of integrated guidance and control. However, it also retains the advantages of the conventional guidance then control philosophy by retaining the timescale separation between translational and rotational dynamics explicitly. Simulation studies demonstrate that the proposed technique is effective in bringing the vehicles into formation quickly and maintaining the formation.

A split-phase induction motor is fed from two three-phase voltage source inverters for speed control. This study analyses carrier-comparison based pulse width modulation (PWM) schemes for a split-phase motor drive, from a spacevector perspective. Sine-triangle PWM, one zero-sequence injection PWM where the same zero-sequence signal is used for both the inverters, and another zero-sequence injection PWM where different zero-sequence signals are employed for the two inverters are considered. The set of voltage vectors applied, the sequence in which the voltage vectors are applied, and the resulting current ripple vector are analysed for all the PWM methods. Besides all the PWM methods are compared in terms of dc bus utilisation. For the same three-phase sine reference, the PWM method with different zero-sequence signals for the two inverters is found to employ a set of vectors different from the other methods. Both analysis and experimental results show that this method results in lower total harmonic distortion and higher dc bus utilisation than the other two PWM methods.

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Humans are the most advanced creatures of the nature. Accordingly it can be stated that humanoid robots are the most advanced creatures of human beings. Among the man-made systems such as automobile, hand-phones and multimedia devices, robots of future will hopefully be the most ideal assistants to human beings. During several decades of research, development projects aimed at building bipedal and humanoid robots has been increasing at a rapid rate. A brief review of current activities in the development of bipedal humanoid robotics is provided in this paper. The dynamic modelling of biped robotic system in the current trend is also described. The main objectives for using bipedal robots are introduced and bipedal locomotion as well as its dynamic behaviors in different fields are also considered. The use of dynamics of different kinds of mechanical systems in the field of humanoid robotics is also emphasized. Finally, a list of few projects in this field is provided.