The Development of an Autonomous Library Assistant Service Robot

Abstract

This chapter describes the complete development of a service robot primarily through localization and navigational algorithms and human-robot interaction systems. The service robot was applied as a library assistant robot and its implementation was discussed and evaluated. The chapter was divided into two main topics, the localization system and the human interaction system. The localization system consists of simple modular systems incorporating fusion of odometry, monocular vision and EKF validated sonar readings. The localization method proposed here is a continuous localization process rather than a single localization step and results in fast low cost localization within a specific indoor environment. As the localization process is continuous odometry errors do not have time to accumulate, which implies that the initial position estimation using just basic odometry is relatively accurate. This allows the robot to apply the individual localization procedure for each specific location based on odometry alone. The reduction in image processing techniques such as the use of a monocular vision system rather then a stereo vision system, straight line extraction and simplified vanishing point estimation result in a fast and very effective localization system. The use of simple feature extraction (i.e. straight line extraction) in the algorithm implies that even in adverse lighting conditions it is always possible to extract the acquired information. Even if only partial features are extracted, this is still sufficient for the algorithm to operate correctly. The fact that the robot uses a very simple a priori map and does not use pre-recorded images to aid localization, results in faster