The method for automatic control of a ship with directional instability

A method for creating an automatic control system for a ship with directional instability has been developed. As part of the tests of a small-sized unmanned vessel, a control diagram was built. It showed that the vessel is unstable along its route. It became necessary to add a control channel for the angular acceleration of the vessel to the main channels of the PID regulator. The PID-U regulator has a significant advantage in controlling an unstable vessel on the route over a standard PID regulator due to the channel of angular acceleration; the regulator monitors the angular speed and compensates it with control actions. The disadvantage of the method is difficulties in finding the angular acceleration of the vessel, since, gyroscopic sensors installed on vessels provide data only on the route and angular speed. Simple integration of the angular speed to determine the acceleration can result in errors, especially in wind-wave conditions. The mathematical observer based on the Kalman filter can be used. The results of operation modeling forthis regulator are described.

Fractional-Order Approximation of PID Controller for Buck–Boost Converters

Viability of a fractional-order proportional–integral–derivative (PID) approximation to regulate voltage in buck–boost converters is investigated. The converter applications range not only to high-power ones but also in micro/nano-scale systems from biomedicine for energy management/harvesting. Using a classic closed-loop control diagram the controller effectiveness is determined. Fractional calculus is considered due to its ability at modeling different types of systems accurately. The non-integer approach is integrated into the control strategy through a Laplacian operator biquadratic approximation to generate a flat phase curve in the system closed-loop frequency response. The controller synthesis considers both robustness and closed-loop performance to ensure a fast and stable regulation characteristic. A simple tuning method provides the appropriate gains to meet design requirements. The superiority of proposed approach, determined by comparing the obtained time constants with those from typical PID controllers, confirms it as alternative to controller non-minimum phases systems. Experimental realization of the resulting controller, implemented through resistor–capacitor (RC) circuits and operational amplifiers (OPAMPs) in adder configuration, confirms its effectiveness and viability.

Design of Control Interface for a SCARA Manipulator with Subactuated Final Effector

The decoupled control of robots eases the generation of trajectories of position, speed and acceleration, as well as the combination of sequences of movement in the joints. The aim of this work is to develop an application for motion control, integrating a virtual model into a prototype SCARA manipulator of 4 DOF. The methodology consists: 1. Definition of the manipulator's workspace; 2. Preparation of the control diagram in LabVIEW; 3. Configuration and communication with Arduino hardware. 4. Development of the interface for simultaneous movements; 5. Configuration of the communication interface with SolidWorks. Developing such integration requires particular hardware characteristics that support simulation and communication environments between the different software mentioned, as well as the acquisition and processing of analog signals used in the control algorithm applied to the model, with Lagrange polynomials and direct and inverse kinematics modelling by the Denavit-Hartenberg method.

Soft-Charging Effects on a High Gain DC-to-DC Step-up Converter with PSC Voltage Multipliers

This paper proposes a split-phase control diagram for a new design of a DC-to-DC boost converter which is called PSC-boost and studies its performance. The PSC-boost has two sides, the primary is a PSC converter and the secondary is a DC-to-DC boost converter. The effect of applying the split-phase control diagram helps reduce the output impedance successfully and increases efficiency by 3%. The simulated and analytical results have been proven to validate the effect of the split-phase diagram. The simulated design contains five switches, five capacitors, seven diodes, and three inductors to step up 10V into 160V at 200KHz and 100KHz switching frequencies. The LTspice simulator was used to design and test the proposed model.

Quality Control of Metaxa Cognac

Quality represents all the characteristics and features of a product or service that satisfies individual requirements. In other words, quality is measured by the degree of customer satisfaction regarding a product or service. The implementation of the control diagram is studied at the distribution store reception of Metaxa cognac orders. The delivery was performed in boxes of six bottles. The control charts follow the degree of filling of the bottles. The volume of filling was measured on a batch of 36 bottles to establish reliable control limits. The studied sample comprised 36 bottles distributed in six boxes.

Validation method and proficiency test for the determination of free and hydrolysed formaldehyde

Formaldehyde resins are usually used in the textile industry to prevent wrinkling, as well as for conservation of textile artifacts. The International Agency for Research on Cancer (IARC) classified formaldehyde as carcinogenic to humans. There are several regulations regarding the amount of formaldehyde found in textiles, for example Oeko-Tex Standard 100, REACH and European Ecolabel. In the present work, a spectrophotometric method for quantitative determination of free and hydrolyzed formaldehyde extracted through partial hydrolysis by using aqueous extraction was developed and validated. The method is in conformity with SR EN ISO 14184-1:2012 standard. The results of the validation parameters are 0.0117 mg/l for detection limit and 0.039 mg/l for quantification limit. The working field was proved to be linear in 0.15 µg CH2O/ml – 6.00 µg CH2O/ml range with a correlation coefficient of 0.999977. Furthermore, the recovery parameter value is 89.80%. Selectivity was determined in relation to acetic anhydride and the spectrophotometric method was proven to be selective for the quantitative determination of formaldehyde. Besides the validation method, a control diagram has been constructed by measuring a solution of known concentration 10 times. The selected concentrations are 0.16 mg/l and 0.75 mg/l. These solutions are measured before the actual samples. To ensure the accuracy of the results, our laboratory participated to a proficiency test conducted by ASQUAL. The z-score obtained was 0.38 and the number of participating laboratories was 13.

Water Resource Systems Analysis for Water Scarcity Management: The Thames Water Case Study

Optimisation tools are a practical solution to problems involving the complex and interdependent constituents of water resource systems and offer the opportunity to engage with practitioners as an integral part of the optimisation process. A multiobjective genetic algorithm is employed in conjunction with a detailed water resource model to optimise the “Lower Thames Control Diagram”, a set of control curves subject to a large number of constraints. The Diagram is used to regulate abstraction of water for the public drinking water supply for London, UK, and to maintain downstream environmental and navigational flows. The optimisation is undertaken with the aim of increasing the amount of water that can be supplied (deployable output) through solely operational changes. A significant improvement of 33 Ml/day (1% or £59.4 million of equivalent investment in alternative resources) of deployable output was achieved through the optimisation, improving the performance of the system whilst maintaining the level of service constraints without negatively impacting on the amount of water released downstream. A further 0.2% (£11.9 million equivalent) was found to be realisable through an additional low-cost intervention. A more realistic comparison of solutions indicated even larger savings for the utility, as the baseline solution did not satisfy the basic problem constraints. The optimised configuration of the Lower Thames Control Diagram was adopted by the water utility and the environmental regulators and is currently in use.