Matching evaluation of 2D laser scan points using observed probability in unstable measurement environment

In the real environment such as urban areas sidewalk, the laser scanner measurement is unstable due to various noise such as moving object. The unstable measurement makes difficult for mobile robot localization. While, the stable measured object is effective as landmark. And, it is expect that around the stable measured object, the scan points is frequently obtained greater than unstable measurement with multiple scans. Hence, the observed probability of scan point allows to extract the features of stable measured object and decrease the influence of unstable measurement. This paper presents the calculation of the observed probability of laser scan point for mobile robot localization. The observed probability is statistically obtained from multiple scans when obtained in a priori. Using this localization method, our robot moves completely on the pedestrian environment of about 1.2km at Tsukuba Challenge 2011.