Vision-Based Safety-Related Sensors in Low Visibility by Fog.

Bong Keun Kim,Yasushi Sumi

doi:10.3390/s20102812

Abstract

Mobile service robots are expanding their use to outdoor areas affected by various weather conditions, but the outdoor environment directly affects the functional safety of robots implemented by vision-based safety-related sensors (SRSs). Therefore, this paper aims to set the fog as the environmental condition of the robot and to understand the relationship between the quantified value of the environmental conditions and the functional safety performance of the robot. To this end, the safety functions of the robot built using SRS and the requirements for the outdoor environment affecting them are described first. The method of controlling visibility for evaluating the safety function of SRS is described through the measurement and control of visibility, a quantitative means of expressing the concentration of fog, and wavelength analysis of various SRS light sources. Finally, object recognition experiments using vision-based SRS for robots are conducted at low visibility. Through this, it is verified that the proposed method is a specific and effective method for verifying the functional safety of the robot using the vision-based SRS, for low visibility environmental requirements.

Highlights

IntroductionIf it is foggy or rainy, the field of view is blurred, making it harder to observe far than usual
If it is foggy or rainy, the field of view is blurred, making it harder to observe far than usual.If it is expressed in meteorological terms, it is said that the visibility is bad
To understand the relationship between low visibility caused by fog and functional safety of the mobile service robot for outdoor environments, fog very similar to natural fog was artificially made in the fog chamber of the low visibility test facility

Summary

Introduction

If it is foggy or rainy, the field of view is blurred, making it harder to observe far than usual. If it is expressed in meteorological terms, it is said that the visibility is bad. The size of fog is relatively small compared with that of rain or snow, but it is difficult to forecast because the concentration in the air is changed. Since it makes visibility worse, it causes many problems such as traffic accidents. In Japan, fog is frequent in May, June, and July, and the marine accidents are concentrated in this season [2,3]

Objectives

Methods

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Conclusion