Jerzy Garus

Using of soft computing techniques to control of underwater robot

Applying of artificial intelligence techniques to designing of an autopilot for path following control of an underwater robotic vehicle is considered in the paper. The way-point line of sight scheme is incorporated for the tracking of the reference path and four independent fuzzy controllers are used to generate command signals. Parameters of membership functions of input and output are tuned using genetic algorithms. Quality of control is concerned without and in presence of external disturbances. Some computer simulations are provided to demonstrate the effectiveness and robustness of the approach.

Simulation Model of PEM Fuel Cell Operating at Hydrogen and Oxygen

Effective control of a fuel cell requires a proper mathematical model. Plenty of completely described models of PEM fuel cells operating on hydrogen and air are to be found in the literature. However, there is a lack of the models for the PEM fuel cells operating on pure hydrogen and oxygen. The paper proposes a static model of such an energy source. Parameters of the model are determined by the Genetic Algorithms using experimental data gathered during operation of the real hydrogen/oxygen PEM fuel cells stack.

Passive fault tolerant control allocation for small unmanned underwater vehicle

ABSTRACT The paper presents methods of control allocation in a multi-thruster propulsion system of a small torpedo-shaped underwater vehicle. It concentrates on finding an optimal thrust distribution among thrusters for demanded values of propulsive forces and moments. The approach is directed towards minimisation of energy expenditures necessary to obtain required control. Special attention is paid to the unconstrained thrust allocation for both a faultless and faulty work of the propulsion system. The developed algorithms are designed to be modular, interchangeable and highly computationally efficient. Illustrative examples are inserted to demonstrate correctness and simplicity of proposed thrust allocation methods.

Piecewise Control Method of Oxygen Flow in PEM Fuel Cell

The paper presents a method of control of an oxygen flow in the PEM fuel cell without recirculation. The proposed procedure of finding an optimal value of the oxygen flow basis on comparing a current voltage of the cell with a reference one obtained from a static model of the PEM fuel cell. Simulation results show that such value of the flow is obtained for a limited number of steps. It allows to reduce the oxygen usage assuring safe operation of the fuel cell.

Modelling of Underwater Robotic Vehicle Motion with Using of Genetic Algorithms

The utilization of underwater robotic vehicles has known an increasing importance in many marine activities. The robotic vehicle is equipped with a propulsion system and controlled by a human operator. To simplify tasks of the operator, a control system guaranteeing the automation of elementary robot’s behaviours is often applied. In the paper, a control system supporting the robot spatial motion along a reference path is presented. A waypoint line-of-sight scheme is incorporated and Genetic Algorithms are applied to calculate command signals. Selected results of computer simulations are inserted to demonstrate quality and correctness of the proposed approach.

Thrust Allocation in Propulsion System of Underwater Robotic Vehicle via Linear Programming

This paper focuses on a problem of power distribution in a multi-thrusters propulsion system of an underwater robot. The presented thrust allocation methods are directed towards minimization of energy expenditures necessary to obtain required control. A power/thrust relation is mapped by a linear function. Such approach allows using linear programming (LP) techniques to finding an optimal thrust allocation for demanded propulsive forces and moments. The LP models of thrust distribution are regarded for unconstrained and constrained allocation control.

Control-Oriented Modelling of Spatial Motion of Autonomous Underwater Vehicle

Modelling of three-dimensional motion of an underwater vehicle along a time-varying reference trajectory with predefined speed profiles is presented in the paper. A nonlinear mathematical model with unknown nonlinearities describes the vehicle’s dynamics. Command signals are generated by an adaptive autopilot consisting of three independent controllers with a parameter adaptation law implemented. A control performance is guaranteed by suitably choosing design parameters. Selected results of computer simulations are inserted to demonstrate quality and effectiveness of the approach.

Recognition of objects in video images using the segmentation algorithm

This paper attempts to develop a segmentation algorithm applicable to the issue of recognizing objects in video images. The paper presents the steps of the algorithm with a discussion of techniques used in mathematical morphology, filtration and gradient methods. Also there were presented examples of the results of a verification researches.

Simulation model of fuel cell energy systems for AUV

A paper presents a simulation model of the PEM Fuel Cell designed to supply an autonomous underwater vehicle. The model was implemented in MATLAB/Simulink environment after considerable simplifications. The developed simulator is a useful tool to analyze the main electrical quantities regarding the fuel cell under changing operating conditions for given values of gas temperature and pressure.

The analysis of the DS CDMA transmission — Studies in the environment of real signals

The paper presents a method of the DS CDMA signals with BPSK modulation detection through the examination of the enhanced signal spectrum density. On the base of experiments carried out on the real radio communication signals the impact of a narrowband emission occurring in the examined frequency band on the detection process effectiveness was shown. The results of the experiment aimed at the detection of the satellite navigation system GPS signals are presented.