Abstract: The air-duct cleaning robot(ADCR) is a kind of automation equipment to clean the ventilation-duct of the cental air-conditioning system. In order to improve its capability of autonomous navigation in an unknown, enormous and enclosed air-duct network, a low-cost robot simultaneous localization and mapping(SLAM) scheme is proposed. By combing an inertial measurement unit(IMU) with a stereo camera and fusing measurements of both sensors with the Rao-Blackwellized paticle filter, the proposed scheme can restrain drift of IMU, and provide fast dynamic full six-dimensional ego-motion information (including position, attitude and velocity) of the ADCR and reliable three-dimensional visual information inside the ventilation-duct. Furthermore, a bidirectional data association method based on the geometry compatibility and landmark’s visual appearance is proposed to guarantee robustness of visual landmarks. The performance of the proposed scheme is proved to be effective with experiments.

Key words: Air-duct cleaning robot, Inertial navigation, Particle filter, Simultaneous localization and mapping, Stereo vision