Mobile robot map generation by integrating omnidirectional stereo and laser range finder

This paper describes a map generation method using an omnidirectional stereo and a laser range finger. Omnidirectional stereo has an advantage of 3D range acquisition, while it may suffer from a low reliability and accuracy in range data. Laser range finders have advantage of reliable acquisition of data, while they usually obtain only 2D range information. By integrating these two sensors, a reliable map can be generated. Since the two sensors may detect different parts of an object, a separate probabilistic grid map is first generated by temporal integration of data from each sensor. The resultant two maps are then integrated using a logical integration rule. An ego-motion estimation method is also described, which is necessary for integration of sensor data obtained at different positions. Experimental results on autonomous navigation in unknown environments show the feasibility of the method.