In this study, a module combining various types of sensors was developed to increase search efficiency inside collapsed buildings. It was designed to be less than 70 mm in diameter so that it can be put into narrow spaces, and is equipped with a small & high-performance processor to process multiple sensor data. To increase sensor data processing efficiency, multi thread based software was configured, and the images were combined and transmitted to ensure time synchronization of multi-channel video data. A human detection function based on sound source detection using two microphones was implemented. The developed multi-sensor module was tested for operation by mounting it on a snake-type robot in a test bed simulating a disaster site. It was confirmed that the visible range of the robot to which the multi-sensor module was applied was expanded, and the ability to detect human and low-light human detect was secured.

In this study, we proposed microphone array and algorithm for sound source localization based on GCC-PHAT for the robot searching victims in a narrow space. Through frequency domain analysis, we designed filter to make algorithm react only to the sound with a human voice frequency. Additionally, calibration algorithm was integrated to solve the problem of the update cycle of result value becoming very short when passing through the filter, presenting difficulty in checking the value. Results obtained through experiments verified the performance of the proposed microphone array and sound source localization algorithm.