Abstract
This paper describes a robust localization system, similar to the used by the teams participating in the Robocup Small size league (SLL). The system, developed in Object Pascal, allows real-time localization and control of an autonomous onmidirectional mobile robot. The localization algorithm is done resorting to odometry and global vision data fusion, applying an extended Kalman filter.

Abstract
This paper describes the realistic simulation of a Lego Mindstorms NXT based robot. The presented approach does not replace the training with hardware but is an important complement, since it allows to develop robot software without accessing to the real hardware.

Abstract
This article reports on the RoboCup-2003 event. RoboCup is no longer just the Soccer World Cup for autonomous robots but has evolved to become a coordinated initiative encompassing four different robotics events: (1) Soccer, (2) Rescue, (3) junior (focused on education), and (4) a Scientific Symposium. RoboCup-2003 took place from 2 to 11 July 2003 in Padua (Italy); it was colocated with other scientific events in the field of AT and robotics. In this article, in addition to reporting on the results of the games, we highlight the robotics and AT technologies exploited by the teams in the different leagues and describe the most meaningful scientific contributions.

Abstract
This paper presents a nonlinear model-based predictive controller (NMPC) for trajectory tracking of a four-wheeled omnidirectional mobile robot. Methods of numerical optimization to perform real-time nonlinear minimization of the cost function are used. The cost function penalizes the robot's position error, the robot's orientation angle error, and the control effort. Experimental results of the trajectories following and the performances of the methods of optimization are presented. Copyright (C) 2007 John Wiley & Sons, Ltd.

Abstract
This article presents a design of a four-wheeled omnidirectional mobile robot for RoboCup Middle Size League. The mobile robot was built for the 5dpo-2000 Robotic Soccer team from the Department of Electrical and Computer Engineering at the University of Porto, Portugal. The robot's architecture and communication structure are presented. A nonlinear modeling and a motion analysis based on the dynamics, kinematics, and DC motors are analyzed. This model could find the nonlinear saturation elements, such as limits of current of the motors, amplitude of the applied voltage in the motors, and frictions related to equation of motion. Simulation results are provided to demonstrate the performance of the proposed project.

Abstract
This paper presents a nonlinear modeling approach of an omnidirectional mobile robot to predict the robot behavior in a model-based predictive controller (MPC). Parameters related to dynamic equations of the robot and restriction of the robot's motors are considered in the modeling. Simulation results and real results of navigation are provided to demonstrate the performance of the proposed modeling approach. Copyright 2009 ACM.