Determining Hit Time and Location of the Ball in Humanoid Robot League

Goalkeeper robot in the league of humanoid robots has a key role so that its wrong decision and incorrect jump can cause changes in the result of a competition. This paper presents a method to detect the ball on the ground during the match, determine the coordinates of the ball with respect to the robot, calculating the speed and direction of the ball and eventually the time and place that the ball hits the goal. This can be the basis of making correct decision for the goalkeeper robot. The method is based on chasing the ball and calculating the coordinates of collision point. The results of applying this method on small size humanoid robot was excellent, except for the situations that inadequate rate of imaging lead to losing the ball or mistaken a similar object for the ball by the robot, quite right decisions in other states were made.