Browsing by Author "McPhillips, Graeme"

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Open Access
    The control of semi-autonomous robots
    (2004) McPhillips, Graeme; Tapson, Jonathan
    Robotic soccer is an international area of research which involves multiple robots collaborating in an adversarial and dynamic environment. Although many different forms gf robotic soccer are played, the University of Cape Town (UCT) chose the RoboCup small» sized robot league, officially known as the F180 RoboSoccer league, as a means of pursuing robotics research within the institution. The robot soccer game is played between two teams of ï¬ ve robots on a carpeted surface that is 2.8 m long by 2.3 m wide. The robots have their own on-board controllers that execute instructions sent to them from a computer-based artiï¬ cial intelligence (AI) system. In order for the AI system to keep track of all the robots and the ball (an orange golf ball), a global vision system is utilised. This global vision system uses images captured from either one or multiple digital cameras mounted above the ï¬ eld of play to determine the position and orientation of the team's robots, the position of the other teams' robots and ï¬ nally the position of the ball. In the true spirit of competition and furthering research, the rules which govern F180 RoboSoccer league cover only the basic format of the game thereby leaving various aspects of the robots, global vision system and AI design open for development. Since there was no RoboSoccer research in existence at UCT prior to the inception of this researcher's Masters' thesis the task included both the establishment of this format of robotics research at the institution as well as the actual design and development of the robots and the associated components as outlined below. Developing a team of robots requires a wide array of knowledge and the research undertaken was accordingly broken into three key components; the design of the robots (which included their related electronics and on-board controller), the design of a vision system and the design of an Al system. The main focus of this author's work was on the design of the robots as well as the overall structuring and integration of the UCT F180 RoboSoccer team. In addition, the areas of the global vision system and AI system that were covered within the scope of this thesis, are also presented. Prototypes were developed and in the ï¬ rst the main emphasis was placed on the movement of the robot, with the design of the kicking mechanism only occurring subsequent to this. After the ï¬ rst competition in 2002, this ï¬ rst design was abandoned in favour of developing a simpler robot with which to continue development. This simpler robot became the second prototype which, after testing, was reï¬ ned into the competition robot for 2003. During this period, the Al and global vision systems were developed by undergraduate thesis students. This research was then incorporated where applicable and, ï¬ nally, the residual problem areas were again addressed by a collaboration of staff and students. Whilst the design and implementation of the robots was very successful, the vision system was not successfully implemented before the competition in 2003. Although an autonomous game of soccer was not successfully played in the 2003 competition, the UCT F180 RoboSoccer team had made a great deal of progress towards this goal and, consequently, a strong foundation for future robotic soccer research within UCT has been established.
  • Thumbnail Image
    Item
    Open Access
    Omnidirectional robotic platform : the control of an omnidirectional robotic platform for use in robot soccer
    (2008) Levesque, Sally-Ann; McPhillips, Graeme; Marais, Stephen; Reed, Brandon
    The University of Cape Town competes in a national robot soccer competition. Teams of five small robots compete in the game of soccer without any human intervention. The robots are controlled by the artificial intelligence on a host computer connected to an overhead imaging system. The host computer controls the robots by sending them instructions via wireless communications. The robot soccer platform calls for the integration of electronic, mechanical and computer technologies and provides an exciting area for research. UCT first competed in the robot soccer competition in 2003, using differential drive robots designed by Graeme McPhillips. Research has shown that in the international robot soccer competition, teams are replacing their differential drive robots with omnidirectional robots – robots which can move in any direction without first changing their orientation to face the direction of motion. These robots have proved to be highly manoeuvrable and the winning teams in the small robot league are consistently those that use omnidirectional robots. In 2004, Craig Inman-Bamber designed and implemented UCT’s first omnidirectional robot platform. It is this platform that this dissertation is concerned with controlling. Electronic components were designed and implemented and software code written to control the robot in an omnidirectional manner.