Abstract: For the problem that illumination change causes color shiftting and affects the accuracy of color recognition in the medium group of RoboCup competition， this paper proposes a color recognition method based on illumination changed compensation. This method first uses the historical information of the ball to predict its position. After finding the ball by using the method of reverse projection based on color histogram in a small area， it calculates illumination changing rate through the changes of ball’s brightness histogram to dynamically compensate the color lookup table. Experiments show that this method can improve the illumination adaptive of color recognition.

Key words: medium group of soccer robots, illumination changing rate, reverse projection, color lookup table