An improved distance measurement method for four-legged robots based on the colour region

In a robot soccer game, robot's constant movements become a great challenge in the distance measurement. This paper proposes an improved method of distance measurement, which is based on the color region, for Sony four-legged robots. The proposed method improves much the conventional unvarying distance measurement model based on a single camera by taking into account the dynamics of the robot pose and locomotion. The changes of the robot pose and the height of the robotpsilas gravity centre are considered throughout the accelerometer filtering and the robot model analysis. The distance between a robot and an object, for any pose and locomotion of the robot, is therefore accurately calculated by coordinate transformations. Experimental results validate the proposed method.