Self-Driving Algorithm and Location Estimation Method for Small Environmental Monitoring Robot in Underground Mines

Abstract

In underground mine environments where various hazards exist, such as tunnel collapse, toxic gases, the application of autonomous robots can improve the stability of exploration and efficiently perform repetitive exploratory operations. In this study, we developed a small autonomous driving robot for unmanned environmental monitoring in underground mines. The developed autonomous driving robot controls the steering according to the distance to the tunnel wall measured using the light detection and ranging sensor mounted on the robot to estimate its location by simultaneously considering the measured values of the inertial measurement unit and encoder sensors. In addition, the robot autonomously drives through the underground mine and performs environmental monitoring using the temperature/humidity, gas, and particle sensors mounted on the robot. As a result of testing the performance of the developed robot at an amethyst mine in Korea, the robot was found to be able to autonomously drive through tunnel sections with ∼28 m length, ∼2.5 m height, and ∼3 m width successfully. The average error of location estimation was approximately 0.16 m. Using environmental monitoring sensors, temperature of 15-17 • C, humidity of 42%-43%, oxygen concentration of 15.6%-15.7%, and particle concentration of 0.008-0.38 mg/m 3 were measured in the experimental area, and no harmful gases were detected. In addition, an environmental monitoring map could be created using the measured values of the robot's location coordinates and environmental factors recorded during autonomous driving.

Autonomous Driving Robot That Drives and Returns along a Planned Route in Underground Mines by Recognizing Road Signs

“…In the previous studies for developing autonomous robots utilized in underground mines [22][23][24][25][26], the robots were forced to drive along a simple one-way route. However, this study demonstrated that autonomous robots can drive complex multipoint routes in underground mines while recognizing the road signs using a machine-vision-based algorithm.…”

“…In the mining industry, several studies of autonomous driving technology have been conducted in underground mining environments using autonomous robots [16][17][18][19][20][21][22][23][24][25][26]. Baker et al [27] developed "groundhog", an autonomous driving robot that can be used even in underground mines having poor road conditions.…”

Gas source localization and mapping with mobile robots: A review

“…(a) ERP‐42 robot for environmental monitoring in underground mines. Reproduced from Kim and Choi (2021). (b) ARMEx robot based on the Husky A200 platform for remote methane detection and mapping with TDLAS sensor.…”

“…In general, UGVs are better suited to applications which require a denser coverage of gas concentration measurements collected over a long period of time. Some of which include locating and mapping the distribution of methane at landfill sites (Hernandez Bennetts et al, 2012), detecting chemicals in underground mines (Kim & Choi, 2021; Martinez et al, 2020), gas pipeline leakage detection (Kroll et al, 2009), and gas source localization of near ground sources.…”

Lab Scale Model Experiment of Smart Hopper System to Remove Blockages Using Machine Vision and Collaborative Robot

“…For example, it was used in the form of building a spatial database for a mine site, entering attribute information to visualize it, or performing a pre-simulation by changing attribute information [16][17][18][19]. Recently, high-resolution databases of mining sites have been constructed using drones [20][21][22][23] and unmanned ground vehicles [24][25][26][27][28][29]. Further, small-scale mining sites using a low-power Bluetooth beacon and a smartphone equipped with short-range communication technology are being developed [30][31][32].…”