Calibration of laser range finder with a genetic algorithm

Abstract

In order to search and rescue the victims in rubble effectively, a 3D map of the rubble is required. As a part of the national project of rescue robot system, we are investigating a method for constructing a 3D map of rubble by teleoperated mobile robots. In previous work, we have developed the second prototype of laser range finder for rubble measurement. The prototype laser range finder consists of a ring laser beam module and two omni-vision cameras. Also, the third prototype, which is more compact than the second one, is newly developed. Our range finder has the features that the omni-directional distance around the range finder can be measured at once and the omni-directional picture image can be captured at the same time. The measurement accuracy of the sensor depends on the adjustment of some parameters. Although we were adjusting the parameters manually so far, this adjustment requires much time and effort. However, it is difficult for manual adjustment to derive fine measurement accuracy. Then, we developed a calibration system which adjusts the parameters using a Genetic Algorithm. In this paper, the third prototype laser range finder and the calibration system are described. The calibration method of the parameters for the laser range finder is also described. The calibration system makes it possible to adjust the parameters easily. Results of calibration by using the constructed calibration system show the availability of the system.