The Mixed Mode fracture behavior of concrete is measured and characterized by investigating a single crack in a double-notched specimen. To obtain the characterization a very stiff biaxial test set-up with a closed loop control is constructed. The opening and sliding components of the Mixed Mode displacement are measured using a specially designed orthogonal gauge, and the measurements are used...

The open-frame structure of work-class ROVs results in significant model uncertainties, and its motion is strongly disturbed by the umbilical cable. To address these problems, this article developed a nonlinear disturbance observer-based super-twisting double-loop sliding-mode control (NDO-STDSMC) method to achieve trajectory tracking with system uncertainties external disturbances. First, new ...

According to the soft-switching pulsed SAW (Submerged arc weld) weld power supply based on the double closed-loop constant current control mode, a small signal mathematic model of main circuit of soft-switching SAW inverter was established by applying the method of three-terminal switching device modeling method, and the mathematic model of double closed-loop phase-shift control system circuit ...

Ships at sea are affected by factors such as waves which will produce a swing phenomenon. By constantly measuring the attitude of the platform and the change in position, a control system is developed to eliminate all interferences and insulate disturbances to stabilize objects on the carrier and maintain dynamic attitude reference accurately. This paper explores controllers of marine platforms...

In this paper, a new guidance law is designed to improve the performance of a homing missiles guidance system in terminal phase. For this purpose first of all, the two dimensions equations of motion are formulated, then the approximation dynamic of missile control loop is added to these equations which are nonlinear whit unmatched uncertainty. Then, a new adaptive back-stepping method is develo...