In response to a need for a more accurate porosity measuring method for small solid samples (approximately 1 g in mass) the porosity measurement sensor using the sensitive capacitive-dependent crystal was developed. In addition, the new idea of excitation of the entire sensor with stochastic test signals is described, and the porosity measuring method is provided. The latter includes the influence of test signals on the weighting function uncertainty. The uncertainty of the porosity measurement is less than 0.1 % (Temp=10–30 ?C).
COBISS.SI-ID: 9078038
This paper describes sliding mode motion controller with disturbance estimation. A novel adaptive fuzzy disturbance estimator works as an estimator of robot dynamics. The adaptation algorithm is derived by using Lyapunov stability theory and provides global asymptotic stability of the state errors. The structure of the disturbance estimator is optimized by the introduction of three fuzzy logic subsystems based on the physical properties of the robot mechanism. Performances of the proposed controller scheme, as well as some practical design aspects, are demonstrated on a direct drive robot.
COBISS.SI-ID: 9124630
This paper addresses improved EMC in SMPC without using EMI filters. A normal and random PWM for dc-dc power converters is used to minimize conductive EMI. The effectiveness of randomization on spreading the frequency spectrum in normal PWM schemes is evaluated by PSD estimations in the low-frequency range. SPICE simulations are used to verify solutions for eliminating EMI sources and achieving EMC improvements. The conductive EMI levels are estimated with DFT and verified to comply with the EN 55025 regulations. The power converter is driven by microC PIC16F876 with normal and randomized PWM
COBISS.SI-ID: 10874390
The work presents a simple and effective design of taper-based higher order mode (HOM) filters that can effectively remove HOMs from the few-mode fibers. For this purpose, a taper manufacturing technique that allows the production of long and highly uniform tapers was developed. A filter performance was demonstrated on a standard single-mode telecommunication fiber operating at 850 nm. The HOM suppression was better than -39 dB, and the insertion loss of the fundamental mode was less than 0.15 dB.
COBISS.SI-ID: 10638358
This paper describes a virtual Web-based laboratory for control design experiments based on MATLAB server and consisting of two virtual laboratories. The first virtual laboratory “Web sisotool” supports structured hands-on experiments. Structured hands-on experiments are welcome for the visualization of hard-to-grasp concepts. The second virtual laboratory offers students an unstructured MATLAB-like environment, called “M-file application”, that allows students to create and design control design experiments by writing MATLAB M-files of their own and executing them on MATLAB server.
COBISS.SI-ID: 12096278