Nevertheless, robust color discrimination is a tough problem because digitized signals are so naive against the slight changes of lighting conditions. Currently, human programmer adjusts key parameters used in discriminating colored objects on site. Self calibration method should be developed, which can expand image processing applications much more widely in general. Currently, color tracking version is commercially available. As long as the initialized color pattern inside each window does not change so much, tracking is almost successful.
More practical way is to use a wider-angle lens.
One extreme of this sort is to use the omni directional vision system to capture the image all around the agent. This sort of lens seems very useful not only acquiring the basic skills but also realizing cooperative behaviors in multi agent environment. Beside vision, typical sensors used in mobile robot research are range finder, sonar, and bumper ones. One good strategy is assign the sensor roles in advance. For example, sonar and bumper sensors are used for obstacle avoidance while vision sensor is used for the target reaching.