A mobile robot system for automatic floor marking

This paper describes a patent awarded system for automatically marking the positions of stands for a trade fair or exhibition. The system has been in operation since August 2003 and has been used for every exhibition in the three main exhibition halls at the Stockholm International Fair since then. The system has speeded up the marking process significantly What used to be a job for two men over 8 h now takes one robot monitored by one man 4 h to complete. The operators of the robot are from the same group of people that previously performed the marking task manually. Environmental features are much further away than in most other indoor applications and even many outdoor applications. Experiments show that many of the problems that are typically associated with the large beam width of ultrasonic sensors in normal indoor environments manifest themselves here for the laser because of the long range. Reaching the required level of accuracy was only possible by proper modeling of the laser scanner. The system has been evaluated by hand measuring 680 marked points. To make the integration of the robot system into the overall system as smooth as possible the robot uses information from the existing computer aided design (CAD) model of the environment in combination with a SICK LMS 291 laser scanner to localize the robot. This allows the robot to make use of the same information about changes in the environment as the people administrating the CAD system. (C) 2006 Wiley Periodicals, Inc.