3Koh K C,Choi H J,Kim J S,et al. Sensor-based navigation of air-duct inspection mobile robots[A]. Proceeding of the SPIE[C]. 2001,Vol.4190. 202-211.
4Liu K,Glenn R,Lawley T J,et al. Stewart-platform-based inlet duct painting system[A]. Proceedings of the IEEE International Conference on Robotics & Automation[C]. 1993.106-113.
5Neubauer W. A spider-like robot that climbs vertically in ducts or pipes[A]. Proceedings of the IEEE International Conference on Advanced Robotic Systems and the Real World[C]. 1994.1178-1185.