Abstract: The traditional calibration methods for omni-directional vision system make the assumptions that the vision system is a single view point system and the shape of the omni-directional mirror is symmetric in every direction.As the assumptions are hard to meet in applications，the calibration precision may be affected greatly.A new model-free calibration method is designed according to the characteristic of the omni-directional vision.The new method can be applied in the calibration of all kinds of catadioptric omni-directional vision systems with good precision without making the above assumptions.After applying the new method in the calibration of the omni-directional vision system of NuBot，the accuracy of robot’s self-localization based on omni-directional vision is obviously improved，and this verifies the efficiency and practicability of the new method.

Key words: omni-directional vision system, calibration, model-free, soccer robot

摘要： 传统的全向视觉系统标定方法假设研究对象满足单视点成像模型且全向反射镜面各向同性，而在实际应用中上述假设往往并不成立，这会对标定精度带来很大的影响。针对全向视觉系统成像特点设计了一种新的与模型无关的标定方法，不需要研究对象满足上述约束，适用于对各种折反射式全向视觉系统的标定，具有较高的精度。将其应用于NuBot足球机器人全向视觉系统的标定后，较大地提高了机器人基于全向视觉的自定位精度，验证了标定方法的有效性和实用性。

关键词: 全向视觉系统, 标定, 模型无关, 足球机器人